Original research Peer reviewed
A survey of current feeding regimens for vitamins and trace minerals in the US swine industry  
Un estudio sobre los regímenes actuales de alimentación de vitaminas y microminerales en la industria porcina de los EUA
Sondage sur les régimes actuels d’alimentation en vitamines et minéraux essentiels dans l’industrie porcine américaine
Josh R. Flohr, PhD; Joel M. DeRouchey, PhD; Jason C. Woodworth, PhD; Mike D. Tokach, PhD; Robert D. Goodband, PhD; Steve S. Dritz, DVM, PhD
JRF, JMDR, JCW, MDT, RDG: Department of Animal Sciences and Industry, College of Agriculture, Kansas State University, Manhattan, Kansas. SSD: Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas. Corresponding author: Dr Steve S. Dritz, Kansas State University, Diagnostic Medicine/Pathobiology, 1800 Denison Avenue, Manhattan, KS 66506; Tel: 785-532-4202; Fax: 785-532-4089; dritz@vet.k-state.edu.

RIS citationCite as: Flohr JR, DeRouchey JM, Woodworth JC, et al. A survey of current feeding regimens for vitamins and trace minerals in the US swine industry. J Swine Health Prod. 2016;24(6):290–303.
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Summary

Objective: To describe added vitamin and trace-mineral concentrations used in the US swine industry for breeding and growing pigs.

Materials and methods: A convenience sample survey of nutritionists from 18 US swine production systems representing approximately 2.3 million sows or 40% of the US sow herd was conducted to characterize added vitamin and trace-mineral concentrations in swine diets. Data were compiled by dietary phases to determine descriptive statistics. Nutrients evaluated were vitamins A, D, E, and K; biotin; choline; folic acid; niacin; pantothenic acid; pyridoxine; riboflavin; thiamin; vitamin B12; betaine; vitamin C; carnitine; copper; iodine; iron; manganese; selenium; zinc; cobalt; and chromium. Questions about supplementation of vitamin D from a cross-linked vitamin AD3 beadlet, potential use of natural (d-alpha-tocopherol) vitamin E as a source of vitamin E, and the use of chelated trace minerals were included.

Results: Results indicated variation, but most vitamins and trace minerals were included at concentrations above the total dietary requirement estimates reported by the National Research Council (2012). Chelated sources for partial or complete supplementation of copper, manganese, or zinc ranged from none to 46% and none to 77% for chelated selenium across diet type. The chelated sources were more prevalent in breeding-herd and nursery-pig diets.

Implications: Adding a margin of safety for vitamin and trace-mineral supplementation appears to be standard practice in US swine diets. This survey provides a baseline for supplementation rates of the vitamins and trace minerals used in the US swine industry.

Resumen

Objetivo: Describir las concentraciones adicionadas de microminerales y vitaminas utilizadas en la industria porcina de EUA para cría y cerdos en crecimiento.

Materiales y métodos: Se realizó un estudio de conveniencia de diferentes nutriólogos de 18 sistemas de producción porcina de EUA representando aproximadamente 2.3 millones de hembras o 40% del hato de hembras de EUA para caracterizar las concentraciones adicionadas de microminerales y vitaminas en las dietas porcinas. Se recopilaron los datos por fases dietéticas para determinar la estadística descriptiva. Los nutrientes evaluados fueron las vitaminas A, D, E, and K; biotina; colina; ácido fólico; niacina; ácido pantoténico; piridoxina; riboflavina; tiamina; vitamina B12; betaína; vitamina C; carnitina; cobre; yodo; hierro; manganeso; selenio; zinc; cobalto; y cromo. Se incluyeron preguntas sobre suplemento de vitamina D de una perla de vitamina AD3 de cadena cruzada, uso potencial de vitamina E natural (d-alpha-tocoferol) como fuente de vitamina E, y el uso de microminerales quelatados.

Resultados: Los resultados indicaron variación, pero la mayoría de las vitaminas y microminerales se incluyeron en concentraciones por encima de los estimados de requerimientos dietéticos totales reportados por el Consejo de Investigación Nacional (NRC, por sus siglas en inglés; 2012). En los diferentes tipos de dieta, las fuentes quelatadas para suplemento completo o parcial de cobre, manganeso, o zinc variaron de nada a 46%, y de nada a 77% en el selenio quelatado. Las fuentes quelatadas fueron más prevalentes en las dietas de hatos de cría y en lechones de destete.

Implicaciones: La adición de un margen de seguridad para la suplementación de microminerales y vitaminas parece ser una práctica estándar en las dietas porcinas de EUA. Este estudio provee un punto de partida para los índices de suplementación de vitaminas y microminerales utilizados en la industria porcina de EUA.

Resumé

Objectif: Décrire les concentrations de vitamines et minéraux essentiels utilisées dans l’industrie porcine américaine chez les porcs reproducteurs et les porcs en croissance.

Matériels et méthodes: Un sondage parmi un échantillonnage de convenance de nutritionnistes provenant de 18 systèmes de production porcine américains et représentant environ 2,3 million de truies ou 40% des troupeaux de truies a été mené afin de caractériser les concentrations de vitamines et de minéraux essentiels ajoutées dans les diètes porcines. Les données ont été compilées par phases d’alimention afin de déterminer des statistiques descriptives. Les nutriments évalués étaient les vitamines A, D, E, et K; la biotine; la choline; l’acide folique; la niacine; l’acide pantothénique; la pyridoxine; la riboflavine; la thiamine; la vitamine B12; la bétaïne; la vitamine C; la carnitine; le cuivre; l’iodine; le fer; le manganèse; le sélénium; le zinc; le cobalt; et le chrome. Des questions sur la supplémentation en vitamine D à partir d’une granule contenant une combinaison en vitamines AD3, l’utilisation potentielle de vitamine E naturelle (d-alpha-tocophérol) comme source de vitamine E, et l’utilisation de minéraux essentiels chélatés étaient incluses.

Résultats: Les résultats indiquaient des variations mais la plupart des vitamines et des minéraux essentiels étaient inclus à des concentrations supérieures aux exigences alimentaires totales estimées rapportées par le Conseil National de la Recherche (2012). Les sources chélatées pour une supplémentation complète ou partielle en cuivre, manganèse, ou zinc variaient de 0% à 46% et de 0% à 77% pour le sélénium chélaté parmi les types de diète. Les sources chélatées étaient plus fréquentes dans l’alimentation des troupeaux reproducteurs et des porcelets en pouponnière.

Implications: L’ajout d’une marge de sécurité pour la supplémentation en vitamines et minéraux essentiels semble être une pratique standard dans les diètes porcines américaines. Ce sondage fourni des valeurs de base pour les taux de supplémentation pour les vitamines et les minéraux essentiels utilisés dans l’industrie porcine américaine.

Keywords: swine, trace minerals, vitamins, swine industry, survey
Search the AASV web site for pages with similar keywords.

Received: February 19, 2016
Accepted: April 7, 2016


The proper vitamin and trace-mineral supplementation required to optimize performance, but also minimize unnecessary cost, is an area of limited knowledge for production nutritionists. Most commercial diets are formulated well above NRC (2012)1 requirement estimates at a margin of safety needed to account for potential ingredient concentration variation and bioavailability, fluctuations in daily feed intake, or degradation of vitamins resulting from unfavorable storage conditions. Another factor influencing the added margin of safety is the added cost of a specific vitamin or trace mineral. A notable survey conducted by Coelho and Cousins2 examined vitamin supplementation rates from 23 swine entities. From the survey, researchers found that all entities supplied vitamins at concentrations higher than NRC (1998)3 recommendations. Also, entities in the highest quartile supplied vitamins at rates of two to 10 times that of the lowest quartile. The Coelho and Cousins2 survey showed that a wide range of supplementation rates were used across commercial systems. Ultimately, since that survey was reported, two NRC publications have been distributed, illustrating the long lapse in time since a survey was conducted to examine industry vitamin supplementation rates. To our knowledge, there has never been a survey of the supplementation rates of trace minerals used in commercial diet formulation. Mahan et al4 discussed the potential need to express trace-mineral pig requirements on a digestible basis, which would help account for the impact that exogenous enzymes and mineral sources may have on the requirement for the nutrient. Because of the increased usage of phytase and other enzymes, along with the increased availability of chelated trace-mineral sources, there is interest in characterizing trace-mineral usage in the swine industry. With this information, future research examining various vitamin and trace-mineral concentrations for commercially raised pigs could be conducted. Potential for future research, based on findings of the survey, will help determine vitamin and trace-mineral requirements needed to optimize performance and maximize economic return.

Materials and methods

The procedures for this survey were approved by the Kansas State University Committee for Research Involving Human Subjects. The survey information was gathered in an electronic spreadsheet (Excel 2013; Microsoft, Redmond, Washington). The subjects of the survey were swine producers within the United States. A convenience sampling of nutritionists for the swine producers were contacted via e-mail or telephone from the beginning of March to the end of August of 2014 and were asked if they were willing to participate. Of the 22 nutritionists initially contacted, 18 agreed to be involved with the survey. Those willing to participate were provided the survey spreadsheet, or a telephone interview was conducted to collect their information.

The goal of the survey was to identify industry concentrations of added vitamins and trace minerals in complete diets for different phases of production. The phases of production were nursery (weaning to 23 kg), finishing (23 kg to market), gilt development (pre-breeding), and breeding-herd diet formulations. Producers provided approximate weight breaks for feeding phases within each stage of production, along with the premix specifications, inclusion rates, and inclusion rates of any other added vitamin, vitamin-like nutrients, and trace minerals. Specifications were surveyed only for commercial production systems, not for nucleus or multiplier herds.

Results were compiled and pooled to determine descriptive statistics for the supplementation rates. The descriptive statistics used included average, weighted average (determined by the total number of sows), median, minimum, maximum, 25th percentile (lowest quartile), and 75th percentile (highest quartile). Sow inventories were obtained from the Successful Farming 2013 Pork Powerhouse list,5 and producers who were not on the top 25 producers list were asked to provide a current sow inventory. All values were determined using functions in the spreadsheet and included average, standard deviation (STDEV.S), median, minimum (MIN), maximum (MAX), and 25th and 75th percentiles (QUARTILE.EXC). Weighted averages were calculated using the spreadsheet sumproduct function in which producer supplementation rate was multiplied by the size of the producer (sow herd size), then divided by the total number of sows for all participating producers. In addition, the average supplementation rate was calculated as a ratio to the suggested requirement as provided by the NRC.1 It should be noted that the NRC reports total dietary requirements, while the values we surveyed were those of supplementation rates in vitamin and trace-mineral premixes.

Feeding phases and approximate dietary weight breaks varied from producer to producer; however, results are reported in broad weight ranges that were relatively consistent among all participating producers. Feeding phases were divided into three stages of production, including nursery, finishing, and breeding herd. The nursery diets consisted of phase 1 (weaning to 7 kg), phase 2 (7 to 11 kg), and phase 3 (11 to 23 kg); finishing diets consisted of early-finishing (23 to 55 kg), mid-finishing (55 to 100 kg), late-finishing (100 kg to market), and late-finishing with ractopamine HCl (100 kg to market); and breeding herd diets consisted of gilt development (20 kg to breeding), gestation, lactation, and boar.

Within each dietary phase, the vitamins, vitamin-like substances, and trace minerals of interest were vitamins A, D, E, and K (menadione); betaine; biotin; choline; folic acid; niacin; riboflavin; thiamin; pantothenic acid; pyridoxine; vitamin B12; vitamin C (ascorbic acid); carnitine; copper; iodine; iron; manganese; selenium; zinc; cobalt; and chromium. Participants were also asked to provide the specified source of the nutrient used within each dietary phase in order to distinguish potential differences in the use of vitamin-trace-mineral sources.

Results

In total, 18 US swine production systems participated in the survey, totaling approximately 2,268,900 sows. The systems included the greater Midwest and Southeast regions of the United States. Using the December 2013 US Department of Agriculture sow inventory estimate of 5,760,000 (Quarterly Hogs and Pigs Report, 2013),6 this survey sampled information from approximately 40% of the US sow herd.

Nursery

Phase 1 (weaning to 7 kg) nursery diet supplementation rates (Table 1) were provided by 13 producers, which represented approximately 19.4% of the US sow inventory. The average fat-soluble vitamin supplementation rate was 4.6 to 11.6 times that of their NRC1 requirement estimates. Vitamin D was supplemented at 11.6 times that of the NRC1 requirement estimate, and a high amount of variation (SD, 2303 IU per kg) occurred in vitamin D supplementation across producers. Other vitamins were supplemented from 0.4 to 5.5 times their NRC1 requirement estimates. Pyridoxine and choline were supplemented below their requirement estimate, presumably because other ingredients in the diet provide adequate concentrations of these nutrients. One producer supplied betaine as a methyl donor rather than choline, and one producer added vitamin C to the weaning-to-7-kg diet. Trace minerals were supplemented from 1.0 to 30.3 times their requirement estimate. Iron and selenium were supplemented at their requirement estimate, and copper and zinc were supplemented well above their requirement estimate, at 18.6 and 30.3 times, respectively. Carnitine was supplemented by one producer, and five producers supplemented chromium to the weaned pigs during this phase.

Table 1: Added vitamin and trace-mineral concentrations in phase 1 nursery diets (weaning to 7 kg)*

N† Weighted average‡ Average Ratio to NRC§ Standard deviation Low 25% Median 75% High
Fat-soluble vitamins
A (IU/kg) 13 11,033 10,600 4.8 832.0 8800 9900 9900 11,002 14,630
D (IU/kg) 13 2222 2554 11.6 2303 1542 1705 1995 2200 10,175
E (IU/kg) 13 86.0 73.9 4.6 27.7 44.0 59.6 66.0 77.0 150.0
K (mg/kg) 13 3.7 4.0 7.7 0.53 3.1 3.5 4.0 4.4 4.4
Other vitamins
Biotin (mg/kg) 11 0.44 0.33 4.2 0.90 0.15 0.22 0.26 0.33 1.06
Choline (mg/kg) 6 202.4 245.5 0.4 167.0 129.8 129.8 166.8 385.0 550.0
Folic acid (mg/kg) 11 1.6 1.6 5.5 4.8 0.77 0.99 1.5 1.7 3.6
Niacin (mg/kg) 13 45.8 49.1 1.6 11.4 36.1 43.6 45.3 52.4 82.5
Pantothenic acid (mg/kg) 13 32.1 30.1 2.5 3.6 25.3 27.5 29.7 33.0 37.6
Riboflavin (mg/kg) 13 9.5 9.0 2.3 1.0 7.7 8.1 8.8 9.9 11.0
Thiamin (mg/kg) 5 2.9 2.9 1.9 0.42 2.2 2.4 3.1 3.3 3.3
Vitamin B6 (mg/kg) 11 4.0 3.7 0.5 0.97 2.2 3.1 4.0 4.4 5.5
Vitamin B12 (µg/kg) 13 41.1 38.9 2.0 0.24 33.0 33.4 38.5 44.0 45.1
Trace minerals
Copper (mg/kg) 13 157.3 111.4 18.6 96.9 11.2 15.8 157.7 194.0 248.5
Iodine (mg/kg) 13 0.62 0.52 3.7 0.21 0.30 0.34 0.50 0.68 1.0
Iron (mg/kg) 13 104.6 103.5 1.0 15.9 89.8 91.3 99.8 109.9 150
Manganese (mg/kg) 13 38.2 36.6 9.1 7.7 26.5 30.0 34.9 39.8 55.0
Selenium (mg/kg) 13 0.30 0.30 1.0 0.004 0.29 0.30 0.30 0.30 0.30
Zinc (mg/kg) 13 3173 3032 30.3 599.5 1906 2804 2931 3475 4002
Conditionally essential nutrients
Betaine (mg/kg) 1 960.0 960.0 NA ND 960.0 ND 960.0 ND 960.0
Carnitine (mg/kg) 1 50.0 50.0 NA ND 50.0 ND 50.0 ND 50.0
Chromium (mg/kg) 5 0.20 0.20 NA 0.00 0.20 0.20 0.20 0.20 0.20
Vitamin C (mg/kg) 1 250.0 250.0 NA ND 250.0 ND 250.0 ND 250.0

*   Thirteen producers’ nutritionists provided information for phase 1 nursery diets, totaling approximately 1,115,400 sows (19.4% of the US sow herd). All reported values are on a complete-feed basis.

†   N indicates the number of producers adding concentrations of a nutrient.

‡   Weighted averages were calculated using the sumproduct function of Excel 2013 (Microsoft) in which the producer supplementation rate was multiplied by the size of the producer (sow herd size). After summing those products, they were divided by the total number of sows for all participating producers.

§   Values represent average supplementation rates as a proportion to total dietary vitamin and trace-mineral requirements from the NRC 2012.1

NA = not applicable; NRC1 does not list a requirement for conditionally essential nutrients.

ND = not done; standard deviation (SD) is not meaningful for N of 1, or for the 25th and 75th percentiles for N = 1 or N = 2.

Phase 2 (7 to 11 kg) nursery diet supplementation rates (Table 2) were provided by 17 participants, representing 39.0% of the US sow herd. Fat-soluble vitamins were supplemented at rates ranging from 4.0 to 8.1 times their NRC1 requirement estimates. Other vitamins were supplemented at rates from 0.4 to 7.1 times their respective NRC1 requirement estimates. Similar to phase 1 diets, added choline and pyridoxine were supplemented below NRC1 requirement estimates, presumably because other ingredients provide these nutrients. Trace minerals were supplemented at rates of 1.0 (selenium) to 9.1 times their NRC1 requirement estimates, except for zinc (20.8) and copper (19.7), which are likely supplemented at high concentrations for growth promotion purposes. One producer supplemented betai

Table 2: Added vitamin and trace-mineral concentrations in Phase 2 nursery diets (7 to 11 kg)*

N Weighted average Average Ratio to NRC§ Standard deviation Low 25% Median 75% High
Fat-soluble vitamins
A (IU/kg) 17 12,129 10,274 4.7 3373 2996 9900 9900 11,002 19,415
D (IU/kg) 17 1912 1773 8.1 527.8 706.2 1487 1760 2160 2849
E (IU/kg) 17 71.3 63.4 4.0 25.1 26.4 44.0 60.1 77.0 125.0
K (mg/kg) 17 4.8 4.0 7.8 1.5 1.2 3.1 4.0 4.4 8.4
Other vitamins
Biotin (mg/kg) 11 0.37 0.35 7.1 0.22 0.15 0.22 0.29 0.33 0.99
Choline (mg/kg) 4 224.4 209.0 0.4 97.0 129.8 129.8 187.0 308.0 330.0
Folic acid (mg/kg) 11 1.8 1.8 5.9 0.90 0.88 1.1 1.5 2.2 3.5
Niacin (mg/kg) 17 51.3 47.7 1.6 15.2 25.1 41.1 45.1 50.8 82.5
Pantothenic acid (mg/kg) 17 35.6 29.7 3.0 8.6 10.6 26.4 29.3 33.0 54.8
Riboflavin (mg/kg) 17 9.7 8.6 2.5 2 3.3 7.7 8.4 9.9 13.6
Thiamin (mg/kg) 5 2.9 2.9 2.9 0.42 2.2 2.4 3.1 3.3 3.3
Vitamin B6 (mg/kg) 9 4.0 4.0 0.6 0.81 3.1 3.3 4.0 4.6 5.5
Vitamin B12 (µg/kg) 17 46.0 38.5 2.2 11.9 16.5 33.0 38.5 44.0 73.7
Trace minerals
Copper (mg/kg) 17 169.1 118.2 19.7 96.0 11.2 15.0 156.5 195.1 248.5
Iodine (mg/kg) 17 0.62 0.54 3.9 0.21 0.30 0.34 0.55 0.70 1.0
Iron (mg/kg) 17 118.0 106.4 1.1 29.0 61.1 89.8 99.8 110.1 166.7
Manganese (mg/kg) 17 33.5 35.0 8.8 7.8 24.2 29.1 33.1 39.5 55.0
Selenium (mg/kg) 17 0.29 0.29 1.0 0.02 0.22 0.30 0.30 0.30 0.30
Zinc (mg/kg) 17 2340 2081 20.8 751.4 75.0 1908 2050 2527 3294
Conditionally essential nutrients
Betaine (mg/kg) 1 960.0 960.0 NA ND 960.0 ND 960.0 ND 960.0
Chromium (mg/kg) 5 0.23 0.21 NA 0.03 0.20 0.20 0.20 0.24 0.27

*   Seventeen producers’ nutritionists provided information for phase 2 nursery diets, totaling approximately 2,243,900 sows (39.0% of the US sow herd). All reported values are on a complete-feed basis.

†   N indicates the number of producers adding concentrations of a nutrient.

‡   Weighted averages were calculated using the sumproduct function of Excel 2013 (Microsoft) in which the producer supplementation rate was multiplied by the size of the producer (sow herd size). After summing those products they were divided by the total number of sows for all participating producers.

§   Values represent average supplementation rates as a proportion to total dietary vitamin and trace-mineral requirements from the NRC 2012.1

NA = not applicable; NRC1 does not list a requirement for conditionally essential nutrients.

ND = not done; standard deviation (SD) is not meaningful for N of 1, or for the 25th and 75th percentiles for N = 1 or N = 2.

 

ne rather than choline as a methyl donor, and five producers supplemented chromium in phase 2 nursery diets.

Phase 3 (11 to 23 kg) nursery diet supplementation rates (Table 3) were provided by all 18 producers who participated in the survey. Fat-soluble vitamins were supplemented at 4.3 to 7.7 times their respective NRC1 requirement estimates. Other vitamins were supplemented at 1.2 to 6.3 times their respective NRC1 requirement estimates. No producers who participated in the survey supplemented choline in phase 3 nursery diets. Trace minerals were supplemented at rates of 1.0 to 9.8 times their NRC1 requirement estimates, except for copper, which was supplemented at a rate of 31.6 times the pig’s requirement estimate, probably due to its growth-promotion influences. One producer supplemented cobalt in phase 3 nursery diets.

Table 3: Added vitamin and trace-mineral concentrations in Phase 3 nursery diets (11 to 23 kg)*

N Weighted average Average Ratio to NRC§ SD Low 25% Median 75% High
Fat-soluble vitamins
A (IU/kg) 18 10,954 8868 5.1 3676 3630 5940 9434 11,000 18,698
D (IU/kg) 18 1760 1537 7.7 552.2 825.0 979.0 1478 1984 2748
E (IU/kg) 18 51.5 46.9 4.3 20.5 16.5 36.3 43.8 50.2 100.1
K (mg/kg) 18 4.4 3.5 7.1 1.6 1.3 2.4 4.0 4.4 8.1
Other vitamins
Biotin (mg/kg) 7 0.26 0.26 5.2 0.07 0.13 0.22 0.26 0.33 0.33
Folic acid (mg/kg) 6 1.9 1.9 0.0 1.1 0.99 0.99 1.4 3.1 3.5
Niacin (mg/kg) 18 46.2 41.6 6.3 17.6 16.5 26.4 39.2 50.4 82.5
Pantothenic acid (mg/kg) 18 32.1 25.7 1.4 9.7 10.8 19.4 25.1 30.6 52.8
Riboflavin (mg/kg) 18 8.6 7.5 2.9 2.4 3.3 5.5 8.1 9.0 13.2
Thiamin (mg/kg) 2 3.1 3.1 2.5 0.16 3.1 ND 3.1 ND 3.3
Vitamin B6 (mg/kg) 5 4.2 3.5 3.2 1.9 0.88 1.8 4.0 5.3 5.5
Vitamin B12 (µg/kg) 18 42.2 33.2 1.2 13.6 16.5 22.9 30.8 39.8 71.3
Trace minerals
Copper (mg/kg) 18 159.5 158.0 31.6 81.3 11.2 99.5 158.4 200.6 326.5
Iodine (mg/kg) 18 0.55 0.49 3.5 0.25 0.22 0.30 0.36 0.67 1.0
Iron (mg/kg) 18 111.9 104.0 1.0 31.3 60.9 76.7 102.5 122.9 166.7
Manganese (mg/kg) 18 28.0 29.3 9.8 10.9 9.0 24.7 29.8 33.2 55.0
Selenium (mg/kg) 16 0.28 0.29 1.1 0.08 0.14 0.30 0.30 0.30 0.30
Zinc (mg/kg) 18 672.6 401 5.0 959.4 65.8 104.4 120.3 145.8 3030
Conditionally essential nutrients
Chromium (mg/kg) 2 0.26 0.20 NA 0.09 0.13 ND 0.20 ND 0.27
Cobalt (mg/kg) 1 0.39 0.39 NA ND 0.39 ND 0.39 ND 0.39

*   Eighteen producers’ nutritionists provided information for phase 3 nursery diets, totaling approximately 2,268,900 sows (39.4% of the US sow herd). All reported values are on a complete-feed basis.

†   N indicates the number of producers adding concentrations of a nutrient.

‡   Weighted averages were calculated using the sumproduct function of Excel 2013 (Microsoft) in which the producer supplementation rate was multiplied by the size of the producer (sow herd size). After summing those products they were divided by the total number of sows for all participating producers.

§   Values represent average supplementation rates as a proportion to total dietary vitamin and trace-mineral requirements from the NRC 2012.1

NA = not applicable; NRC1 does not list a requirement for conditionally essential nutrients.

ND = not done; SD is not meaningful for N of 1, or for the 25th and 75th percentiles for N = 1 or N = 2.

Finishing

The early-finishing diet (23 to 55 kg) supplementation rates (Table 4) were provided by all 18 survey participants. Fat-soluble vitamins were supplemented at 2.5 to 6.7 times their respective NRC1 requirement estimates.Other vitamins were supplemented from 0.9 to 2.2 times their respective NRC1 requirement estimates. On average, niacin was supplemented below the estimated requirement. Biotin was supplemented in early finishing diets by two producers. Trace minerals were supplemented at rates of 28.1 times copper, 3.0 times iron, 1.4 times iodine, 12.6 times manganese, 1.4 times selenium, and 1.6 times zinc requirement estimates. One producer supplemented cobalt at 0.39 mg per kg.

Table 4: Added vitamin and trace-mineral concentrations in early-finishing diets (23 to 55 kg)*

N Weighted average Average Ratio to NRC§ SD Low 25% Median 75% High
Fat-soluble vitamins
A (IU/kg) 18 5859 5643 4.3 1057 3630 5104 5533 6600 7480
D (IU/kg) 18 984.9 998.8 6.7 166.5 800.8 825.0 990.0 1102 1320
E (IU/kg) 18 25.1 27.1 2.5 7.7 16.1 20.5 26.4 33.2 39.8
K (mg/kg) 18 2.4 2.4 4.7 0.57 1.3 2.0 2.4 2.9 3.3
Other vitamins
Biotin (mg/kg) 2 0.07 0.07 1.2 ND 0.07 ND 0.07 ND 0.07
Niacin (mg/kg) 18 24.9 27.5 0.9 6.9 16.5 24.0 26.4 29.7 49.5
Pantothenic acid (mg/kg) 18 17.4 16.9 2.1 2.9 10.8 14.7 16.5 18.9 22.4
Riboflavin (mg/kg) 18 4.8 4.8 2.0 1.3 3.3 4.0 4.8 5.7 8.8
Vitamin B12 (µg/kg) 18 22.9 22.0 2.2 3.1 15.8 19.8 22.4 23.8 26.4
Trace minerals
Copper (mg/kg) 18 80.8 112.3 28.1 81.3 4.6 66.9 135.7 156.7 242.1
Iodine (mg/kg) 18 0.42 0.42 3.0 0.25 0.22 0.30 0.30 0.45 1.0
Iron (mg/kg) 18 79.8 86.9 1.4 31.3 39.5 70.9 86.0 109.9 123.8
Manganese (mg/kg) 18 21.5 25.2 12.6 10.9 6.6 15.0 29.3 33.0 40.0
Selenium (mg/kg) 18 0.27 0.28 1.4 0.08 0.14 0.27 0.30 0.30 0.30
Zinc (mg/kg) 18 86.0 98.8 1.6 959.4 30.4 78.7 110.0 120.7 150.0
Conditionally essential nutrients
Cobalt (mg/kg) 1 0.39 0.39 NA ND 0.39 ND 0.39 ND 0.39

*   Eighteen producers’ nutritionists provided information for early-finishing diets, totaling approximately 2,268,900 sows (39.4% of the US sow herd). All reported values are on a complete-feed basis.

†   N indicates the number of producers adding concentrations of a nutrient.

‡   Weighted averages were calculated using the sumproduct function of Excel (Microsoft) in which the producer supplementation rate was multiplied by the size of the producer (sow herd size). After summing those products they were divided by the total number of sows for all participating producers.

§   Values represent average supplementation rates as a proportion to total dietary vitamin and trace-mineral requirements from the NRC 2012.1

NA = not applicable; NRC1 does not list a requirement for conditionally essential nutrients.

ND = not done; standard deviation (SD) is not meaningful for N of 1, or for the 25th and 75th percentiles for N = 1 or N = 2.

Mid-finishing (55 to 100 kg) supplementation rates (Table 5) were reported by all 18 producers participating in the survey. Fat-soluble vitamins were supplemented at rates of 2.1 to 5.7 times their respective NRC1 requirement estimates. Other vitamins were supplemented from 0.8 to 3.8 times their respective NRC1 requirement estimates. Similar to the previous phase, average niacin supplementation was below the current NRC1 suggested requirement. Two producers provided added biotin in their mid-finishing diets. Trace minerals were supplemented at rates of 1.6 to 2.7 times the requirement estimate for iodine, iron, selenium, and zinc. Average supplementation rates of copper and manganese were 27.4 and 10.7 times their requirement estimates, respectively.

Table 5: Added vitamin and trace-mineral concentrations in mid-finishing diets (55 to 100 kg)*

N Weighted average Average Ratio to NRC§ SD Low 25% Median 75% High
Fat-soluble vitamins
A (IU/kg) 18 5192 4842 3.7 955.2 3520 3852 5280 5603 6162
D (IU/kg) 18 874.9 859.1 5.7 150.7 550.0 790.7 880.0 990.0 1057
E (IU/kg) 18 22.2 23.3 2.1 7.9 16.1 17.4 19.8 27.7 39.8
K (mg/kg) 18 2.2 2.0 4.0 0.46 1.3 1.7 2.2 2.2 2.9
Other vitamins
Biotin (mg/kg) 2 0.07 0.07 1.1 ND 0.07 ND 0.07 ND 0.07
Niacin (mg/kg) 18 22.0 23.5 0.8 5.1 16.5 20.7 22.0 26.4 34.5
Pantothenic acid (mg/kg) 18 15.4 14.5 2.1 2.4 10.8 12.1 14.5 16.9 17.8
Riboflavin (mg/kg) 18 4.2 4.2 2.1 1.4 2.6 3.3 4.2 4.8 8.8
Vitamin B12 (µg/kg) 18 20.2 18.9 3.8 3.1 13.2 15.8 19.6 22.0 24.2
Trace minerals
Copper (mg/kg) 18 66.6 82.3 27.4 65.0 3.9 10.1 109.1 146.5 161.7
Iodine (mg/kg) 18 0.39 0.37 2.7 0.25 0.16 0.20 0.30 0.39 1.0
Iron (mg/kg) 18 73.7 75.0 1.9 22.5 32.9 61.5 73.3 88.5 123.8
Manganese (mg/kg) 18 19.4 21.4 10.7 10.5 6.4 15.0 22.0 24.5 40.0
Selenium (mg/kg) 18 0.26 0.24 1.6 0.04 0.11 0.20 0.24 0.30 0.30
Zinc (mg/kg) 18 77.8 84.8 1.7 32.3 30.4 61.5 89.1 100.0 131.2
Conditionally essential nutrients
Cobalt (mg/kg) 1 0.31 0.31 NA ND 0.31 ND 0.31 ND 0.31

*   Eighteen producers’ nutritionists provided information for mid-finishing diets, totaling approximately 2,268,900 sows (39.4% of the US sow herd). All reported values are on a complete-feed basis.

†   N indicates the number of producers adding concentrations of a nutrient.

‡   Weighted averages were calculated using the sumproduct function of Excel 2013 (Microsoft) in which the producer supplementation rate was multiplied by the size of the producer (sow herd size). After summing those products they were divided by the total number of sows for all participating producers.

§   Values represent average supplementation rates as a proportion to total dietary vitamin and trace-mineral requirements from the NRC 2012.1

NA = not applicable; NRC1 does not list a requirement for conditionally essential nutrients.

ND = not done; standard deviation (SD) is not meaningful for N of 1, or for the 25th and 75th percentiles for N = 1 or N = 2.

Late-finishing (100 kg to market) vitamin and trace-mineral supplementation rates (Table 6) were provided by all 18 producers who participated in the survey. Fat-soluble vitamins were supplemented at rates of 3.2 times vitamin A, 5.0 times vitamin D, 1.8 times vitamin E, and 3.6 times vitamin K requirement estimates. Other vitamins were supplemented at rates from 0.7 to 3.3 times their NRC1 requirement estimates. Niacin, on average, was supplemented at rates below the current NRC1 requirement. Two producers supplemented biotin in late finishing diets. Trace minerals were supplemented at rates of 1.5 to 2.4 times the requirement estimate for iodine, iron, selenium, and zinc. Average supplementation rates of copper and manganese were 22.0 and 9.3 times their requirement estimates, respectively. One producer only provided added zinc for trace minerals in late-finishing diets.

Table 6: Added vitamin and trace-mineral concentrations in late-finishing diets (100 kg to market)*

N Weighted average Average Ratio to NRC§ SD Low 25% Median 75% High
Fat-soluble vitamins
A (IU/kg) 18 4616 4187 3.2 999.2 2904 3520 3942 4840 6160
D (IU/kg) 18 781.7 745.8 5.0 209.0 412.5 550.0 756.4 897.6 1078
E (IU/kg) 18 19.6 20.0 1.8 6.6 8.1 16.5 17.6 24.0 33.4
K (mg/kg) 18 1.9 1.8 3.6 0.53 1.0 1.3 1.8 2.2 2.9
Other vitamins
Biotin (mg/kg) 2 0.04 0.04 1.0 ND 0.04 ND 0.04 ND 0.07
Niacin (mg/kg) 18 19.4 20.2 0.7 4.8 15.0 16.7 18.3 22.4 33.0
Pantothenic acid (mg/kg) 18 13.6 12.5 1.8 3.1 6.8 11.0 12.3 14.5 18.5
Riboflavin (mg/kg) 18 3.7 3.5 1.8 0.95 2.0 3.1 3.3 4.2 5.5
Vitamin B12 (µg/kg) 18 18.0 16.5 3.3 3.5 7.9 15.2 16.5 18.5 22.2
Trace minerals
Copper (mg/kg) 17 56.3 65.9 22.0 71.0 3.1 8.1 10.0 147.2 160.8
Iodine (mg/k) 17 0.37 0.34 2.4 0.24 0.15 0.18 0.24 0.42 1.0
Iron (mg/k) 17 69.3 66.5 1.7 25.2 30.9 54.1 62.9 80.3 103.1
Manganese (mg/kg) 17 17.7 18.6 9.3 9.8 3.3 14.7 19.4 23.0 40.0
Selenium (mg/kg) 17 0.24 0.22 1.5 0.08 0.12 0.17 0.20 0.30 0.30
Zinc (mg/kg) 18 71.7 73.8 1.5 26.8 30.4 55.0 74.9 90.1 131.2
Conditionally essential nutrients
Cobalt (mg/kg) 1 0.31 0.31 NA ND 0.31 ND 0.31 ND 0.31

*   Eighteen producers’ nutritionists provided information for late-finishing diets, totaling approximately 2,268,900 sows (39.4% of the US sow herd). All reported values are on a complete-feed basis.

†   N indicates the number of producers adding concentrations of a nutrient.

‡   Weighted averages were calculated using the sumproduct function of Excel 2013 (Microsoft) in which the producer supplementation rate was multiplied by the size of the producer (sow herd size), and after summing those products they were divided by the total number of sows for all participating producers.

§   Values represent average supplementation rates as a proportion to total dietary vitamin and trace-mineral requirements from the NRC 2012.1

¶   One producer provided added zinc supplement only for trace minerals in the late-finishing diets.

NA = not applicable; NRC1 does not list a requirement for conditionally essential nutrients.

ND = not done; standard deviation (SD) is not meaningful for N of 1, or for the 25th and 75th percentiles for N = 1 or N = 2.

Supplementation rates of vitamins and trace minerals in late-finishing diets with ractopamine HCl (Table 7) were reported by seven of the 18 producers. Fat-soluble vitamin supplementation rates were 3.4 times vitamin A, 5.2 times vitamin D, 1.9 times vitamin E, and 3.9 times vitamin K requirement estimates. Other vitamins were supplemented at rates from 0.7 to 3.4 times their NRC1 requirement estimates. Niacin, on average, was supplemented at rates below the current NRC1 requirement estimate. Trace minerals were supplemented at rates 1.4 to 2.3 times the requirement estimate for iodine, iron, selenium, and zinc, respectively. Average supplementation rates of copper and manganese were 17.1 and 9.0 times their requirement estimates, respectively. Overall, producers who responded with information on both late-finishing and late finishing diets with ractopamine HCl supplemented 10% more vitamins, 8.5% more trace minerals (copper, iodine, iron, manganese, selenium), and 33% more zinc in those diets that also contained ractopamine HCl.

Table 7: Added vitamin and trace-mineral concentrations in late-finishing diets with ractopamine (100 kg to market)*

N Weighted average Average Ratio to NRC§ SD Low 25% Median 75% High
Fat-soluble vitamins
A (IU/kg) 7 5247 4473 3.4 1099 3520 3630 3960 5500 6160
D (IU/kg) 7 911.0 774.0 5.2 284.9 440.0 550.0 770.0 1008.3 1078.0
E (IU/kg) 7 25.5 21.1 1.9 7.5 10.1 17.6 20.9 27.5 30.8
K (mg/kg) 7 2.2 2.0 3.9 0.48 1.3 1.7 2.0 2.4 2.9
Other vitamins
Niacin (mg/kg) 7 20.2 20.5 0.7 2.9 16.5 18.7 20.7 22.0 24.6
Pantothenic acid (mg/kg) 7 15.6 13.6 1.9 3.7 8.6 11.0 13.0 16.5 18.5
Riboflavin (mg/kg) 7 4.4 3.7 1.9 1.2 2.4 3.1 4.0 4.8 5.5
Vitamin B12 (µg/kg) 7 18.5 16.9 3.4 4.4 9.9 13.2 17.6 19.8 22.0
Trace minerals
Copper (mg/kg) 7 66.2 51.4 17.1 76.6 3.9 8.9 11.5 154.7 159.7
Iodine (mg/kg) 7 0.37 0.29 2.1 0.13 0.20 0.20 0.20 0.37 0.50
Iron (mg/kg) 7 67.1 71.6 1.8 19.6 38.6 64.9 66.5 88.7 99.1
Manganese (mg/kg) 7 19.8 18.0 9.0 10.2 4.1 4.5 20.9 24.9 27.4
Selenium (mg/kg) 7 0.18 0.21 1.4 0.06 0.12 0.15 0.19 0.27 0.28
Zinc (mg/kg) 7 113.9 112.5 2.3 29.6 74.8 99.1 105.2 131.2 160.2
Conditionally essential nutrients
Cobalt (mg/kg) 1 0.35 0.35 NA ND 0.35 ND 0.35 ND 0.35

*   Seven producers’ nutritionists provided information for late-finishing diets with ractopamine, totaling approximately 556,000 sows (9.7% of the US sow herd). All reported values are on a complete-feed basis.

†   N indicates the number of producers adding concentrations of a nutrient.

‡   Weighted averages were calculated using the sumproduct function of Excel 2013 (Microsoft) in which the producer supplementation rate was multiplied by the size of the producer (sow herd size). After summing those products they were divided by the total number of sows for all participating producers.

§   Values represent average supplementation rates as a proportion to total dietary vitamin and trace-mineral requirements from the NRC 2012.1

NA = not applicable; NRC1 does not list a requirement for conditionally essential nutrients.

ND = not done; standard deviation (SD) is not meaningful for N of 1, or for the 25th and 75th percentiles for N = 1 or N = 2.

Breeding-herd diets

Gilt-development diets were provided by 17 producers. When evaluating the gilt developer diets, compared to the suggested growing pig requirements, the average supplementation rates of fat-soluble vitamins were 3.3 times the vitamin A, 4.9 times vitamin D, 2.6 times vitamin E, and 3.0 times vitamin K requirement estimates (Table 8). Compared to gestation requirement estimates, average supplementation rates were 1.1 times vitamin A, 0.9 times vitamin D, 0.6 times vitamin E, and 3.0 times vitamin K requirements. Other vitamins were supplemented at average rates of 2.5 times biotin, 0.8 times choline, 2.5 times folic acid, 0.6 times niacin, 1.4 times pantothenic acid, 1.5 times pyridoxine, 1.3 times riboflavin, 1.0 times thiamin, and 1.5 times vitamin B12 requirement estimates for growing pigs. When evaluating the gilt-developer diets, compared to the suggested gestation requirement estimates, other vitamins were supplemented at an average of 0.6 times biotin, 0.2 times choline, 0.6 times folic acid, 1.8 times niacin, 0.9 times pantothenic acid, 1.5 times pyridoxine, 0.9 times riboflavin, 1.0 times thiamin, and 1.0 times vitamin B12 requirements. One producer supplemented vitamin C at 250 mg per kg. Trace minerals were supplemented at average rates of 5.7 times copper, 3.7 times iodine, 1.6 times iron, 18.6 times manganese, 1.4 times selenium, and 2.0 times zinc growing pig requirement estimates. Compared to gestation requirement estimates, developing gilts were supplemented 2.3 times copper, 3.7 times iodine, 1.2 times iron, 1.5 times manganese, 1.9 times selenium, and 1.2 times zinc requirements. Five producers supplemented chromium at 0.20 mg per kg, and one producer supplemented cobalt at 0.39 mg per kg. Two producers supplemented carnitine at a rate of 50 mg per kg of diet.

Table 8: Added vitamin and trace-mineral concentrations in gilt-development diet (20 kg to breeding)*

N Weighted average Average Ratio to NRC (grower)§ Ratio to NRC (gestation)§ SD Low 25% Median 75% High
Fat-soluble vitamins
A (IU/kg) 17 8452 9405 3.3 1.1 2444 4400 9900 9979 11,000 11,986
D (IU/kg) 17 1339 1621 4.9 0.9 497.2 687.5 1320 1760 1996 2218
E (IU/kg) 17 52.1 62.5 2.6 0.6 29.7 16.5 48.4 60.1 66.0 150.0
K (mg/kg) 17 3.1 3.3 3.0 3.0 1.1 1.3 2.4 3.1 4.4 4.8
Other vitamins
Biotin (mg/kg) 16 0.24 0.29 2.5 0.6 0.09 0.07 0.22 0.26 0.33 0.44
Choline (mg/kg) 13 572.0 541.2 0.8 0.2 132.0 259.6 519.2 519.2 611.6 818.4
Folic acid (mg/kg) 15 1.7 1.7 2.5 0.6 0.73 1.1 1.3 1.5 1.8 3.5
Niacin (mg/kg) 17 34.3 40.3 0.6 1.8 10.8 20.9 38.5 44.0 45.3 55.0
Pantothenic acid (mg/kg) 17 23.5 25.1 1.4 0.9 5.9 15.4 22.0 25.3 28.6 35.0
Riboflavin (mg/kg) 17 6.6 7.5 1.3 0.9 2.0 4.0 5.5 7.7 8.8 9.9
Thiamin (mg/kg) 5 2.0 2.2 1.0 1.0 0.77 1.1 1.7 2.2 2.8 3.3
Vitamin B6 (mg/kg) 12 3.5 3.3 1.5 1.5 1.1 0.88 2.8 3.3 4.0 5.1
Vitamin B12 (µg/kg) 17 30.1 32.1 1.5 1.0 7.7 19.4 27.5 33.0 37.2 44.0
Trace minerals
Copper (mg/kg) 17 25.1 22.9 5.7 2.3 30.0 8.8 12.2 15.0 16.5 136.8
Iodine (mg/kg) 17 0.50 0.51 3.7 3.7 0.30 0.22 0.33 0.38 0.66 1.3
Iron (mg/kg) 17 88.7 97.8 1.6 1.2 23.1 61.1 89.8 99.8 110.0 149.5
Manganese (mg/kg) 17 30.7 37.2 18.6 1.5 14.4 14.2 26.5 33.1 50.0 70.0
Selenium (mg/kg) 17 0.29 0.29 1.4 1.9 0.03 0.20 0.30 0.30 0.30 0.30
Zinc (mg/kg) 17 105.3 121.5 2.0 1.2 26.8 60.8 110.1 123.8 130.0 173.6
Conditionally essential nutrients
Carnitine (mg/kg) 2 50.0 50.0 NA NA 0.00 50.0 ND 50.0 ND 50.0
Chromium (mg/kg) 5 0.20 0.20 NA NA 0.00 0.20 0.20 0.20 0.20 0.20
Cobalt (mg/kg) 1 0.39 0.39 NA NA ND 0.39 ND 0.39 ND 0.39
Vitamin C (mg/kg) 1 250.0 250.0 NA NA ND 250.0 ND 250.0 ND 250.0

*   Seventeen producers’ nutritionists provided information for gilt-development diets, totaling approximately 2,223,600 sows (38.6% of the US sow herd). All reported values are on a complete-feed basis.

†   N indicates the number of producers adding concentrations of a nutrient.

‡   Weighted averages were calculated using the sumproduct function of Excel 2013 (Microsoft) in which the producer supplementation rate was multiplied by the size of the producer (sow herd size). After summing those products they were divided by the total number of sows for all participating producers.

§   Values represent average supplementation rates as a proportion to total dietary vitamin and trace-mineral requirements from the NRC 2012.1 Since the NRC does not list specific gilt-development requirements, the supplementation rates were compared to the NRC requirements of growing pigs from 25 to 50 kg, as well as to gestation requirements, because most strategies for feeding the developing gilt were related to one of these two diet types.

NA = not applicable; NRC1 does not list a requirement for conditionally essential nutrients.

ND = not done; standard deviation (SD) is not meaningful for N of 1, or for the 25th and 75th percentiles for N = 1 or N = 2.

Gestation diet information (Table 9) was provided by 17 of the producers. Fat-soluble vitamins were supplemented at rates of 2.6 times vitamin A, 2.2 times vitamin D, 1.6 times vitamin E, and 7.3 times vitamin K requirement estimates. Other vitamins were supplemented at rates of 1.4 times biotin, 1.3 times folic acid, 4.6 times niacin, 2.3 times pantothenic acid, 3.4 times pyridoxine, 2.2 times riboflavin, 2.2 times thiamin, and 2.4 times vitamin B12 requirement estimates. Choline was supplemented at 0.5 times its requirement estimate due to partial reliance on choline from other ingredients to meet the animal’s requirement. One producer supplemented vitamin C in gestation diets at a rate of 250 mg per kg. Trace-mineral supplementation rates were 1.6 times copper, 3.8 times iodine, 1.3 times iron, 1.5 times manganese, 1.9 times selenium, and 1.2 times zinc requirement estimates. Nine producers supplemented chromium, and one producer supplemented cobalt at 0.39 mg per kg. Two producers supplemented carnitine at a rate of 50 mg per kg.

Table 9: Added vitamin and trace-mineral concentrations in gestation diets*

N Weighted average Average Ratio to NRC§ SD Low 25% Median 75% High
Fat-soluble vitamins
A (IU/kg) 17 9819 10,362 2.6 1026 7698 9900 11,000 11,002 11,986
D (IU/kg) 17 1531 1783 2.2 360.4 1097 1562 1762 2141 2218
E (IU/kg) 17 66.0 70.0 1.6 25.1 44.0 59.0 66.0 73.9 150.0
K (mg/kg) 17 3.5 3.7 7.3 0.99 1.7 2.8 4.0 4.4 4.8
Other vitamins
Biotin (mg/kg) 17 0.26 0.29 1.4 0.07 0.22 0.22 0.24 0.33 0.44
Choline (mg/kg) 17 645.3 610.7 0.5 114.4 389.8 519.6 571.8 713.0 788.7
Folic acid (mg/kg) 17 1.7 1.7 1.3 0.59 1.1 1.3 1.7 1.7 3.5
Niacin (mg/kg) 17 40.5 45.5 4.6 11.7 24.2 41.1 44.0 49.1 82.5
Pantothenic acid (mg/kg) 17 26.8 27.3 2.3 4.0 22.0 24.4 27.5 29.5 35.0
Riboflavin (mg/kg) 17 7.5 8.1 2.2 1.4 5.5 7.3 8.4 9.5 9.9
Thiamin (mg/kg) 5 2.1 2.2 2.2 0.77 1.1 1.7 2.2 2.8 3.3
Vitamin B6 (mg/kg) 13 4.0 3.5 3.4 1.1 0.88 3.0 3.3 4.4 5.1
Vitamin B12 (µg/kg) 17 34.1 35.2 2.4 4.8 27.3 33.0 33.9 38.5 44.0
Trace minerals
Copper (mg/kg) 17 15.0 16.1 1.6 6.0 6.8 13.2 15.0 16.5 35.0
Iodine (mg/kg) 17 0.56 0.53 3.8 0.30 0.16 0.31 0.50 0.68 1.3
Iron (mg/kg) 17 101.8 102.2 1.3 28.8 45.4 89.9 100.0 115.1 165.0
Manganese (mg/kg) 17 32.5 37.6 1.5 13.2 21.2 25.7 38.5 50.0 70.0
Selenium (mg/kg) 17 0.29 0.29 1.9 0.04 0.14 0.30 0.30 0.30 0.30
Zinc (mg/kg) 17 112.9 123.0 1.2 28.3 56.7 108.0 125.0 147.2 165.0
Conditionally essential nutrients
Carnitine (mg/kg) 2 50.0 50.0 NA 0.0 50.0 ND 50.0 ND 50.0
Chromium (mg/kg) 9 0.20 0.20 NA 0.0 0.20 0.20 0.20 0.20 0.20
Cobalt (mg/kg) 1 0.39 0.39 NA ND 0.39 ND 0.39 ND 0.39
Vitamin C (mg/kg) 1 250.0 250.0 NA ND 250.0 ND 250.0 ND 250.0

*   Seventeen producers’ nutritionists provided information for gestation diets, totaling approximately 2,223,600 sows (38.6% of the US sow herd). All reported values are on a complete-feed basis.

†   N indicates the number of producers adding concentrations of a nutrient.

‡   Weighted averages were calculated using the sumproduct function of Excel 2013 (Microsoft) in which the producer supplementation rate was multiplied by the size of the producer (sow herd size). After summing those products they were divided by the total number of sows for all participating producers.

§   Values represent average supplementation rates as a proportion to total dietary vitamin and trace-mineral requirements from the NRC 2012.1

NA = not applicable; NRC1 does not list a requirement for conditionally essential nutrients.

ND = not done; standard deviation (SD) is not meaningful for N of 1, or for the 25th and 75th percentiles for N = 1 or N = 2.

Lactation diet information (Table 10) was provided by 17 of the producers. Fat-soluble vitamins were supplemented at rates of 5.2 times vitamin A, 2.2 times vitamin D, 1.6 times vitamin E, and 7.3 times vitamin K requirement estimates. Other vitamins were supplemented at rates of 1.4 times biotin, 0.5 times choline, 1.3 times folic acid, 4.6 times niacin, 2.3 times pantothenic acid, 3.4 times pyridoxine, 2.2 times riboflavin, 2.2 times thiamin, and 2.4 times vitamin B12 requirement estimates. One producer supplemented vitamin C in lactation diets at a rate of 250 mg per kg of diet. Trace-mineral supplementation rates were 0.8 times copper, 3.8 times iodine, 1.3 times iron, 1.5 times manganese, 1.9 times selenium, and 1.2 times zinc requirement estimates. Nine producers supplemented chromium at a rate of 0.20 mg per kg, and one producer supplemented cobalt at a rate of 0.39 mg per kg. Two producers supplemented carnitine at a rate of 50 mg per kg of diet.

Table 10: Added vitamin and trace-mineral concentrations in lactation diets*

N Weighted average Average Ratio to NRC§ SD Low 25% Median 75% High
Fat-soluble vitamins
A (IU/kg) 17 9997 10,404 5.2 918.5 8415 9900 11,000 11,002 11,986
D (IU/kg) 17 1557 1789 2.2 348.7 1100 1562 1762 2141 2218
E (IU/kg) 17 67.1 70.2 1.6 24.9 44.0 59.0 66.0 73.9 150.0
K (mg/kg) 17 3.5 3.7 7.3 0.99 1.7 2.8 4.0 4.4 4.8
Other vitamins
Biotin (mg/kg) 17 0.29 0.29 1.4 0.07 0.22 0.22 0.24 0.33 0.44
Choline (mg/kg) 17 478.5 533.9 0.5 108.5 259.8 519.6 519.6 609.6 675.6
Folic acid (mg/kg) 17 1.7 1.7 1.3 0.59 1.1 1.3 1.7 1.8 3.5
Niacin (mg/kg) 17 41.4 45.8 4.6 11.7 24.2 41.1 44.0 49.1 82.5
Pantothenic acid (mg/kg) 17 27.3 27.5 2.3 3.7 22.0 24.6 27.5 29.5 35.0
Riboflavin (mg/kg) 17 7.7 8.1 2.2 1.4 5.5 7.3 8.4 9.5 9.9
Thiamin (mg/kg) 5 2.1 2.2 2.2 0.77 1.1 1.7 2.2 2.8 3.3
Vitamin B6 (mg/kg) 13 4.0 3.5 3.4 1.1 0.88 3.0 3.3 4.4 5.1
Vitamin B12 (µg/kg) 17 34.8 35.4 2.4 4.6 27.5 33.0 33.9 38.5 44.0
Trace minerals
Copper (mg/kg) 17 15.0 16.1 0.8 6.0 6.8 13.2 15.0 16.5 35.0
Iodine (mg/kg) 17 0.56 0.53 3.8 0.30 0.16 0.31 0.50 0.68 1.3
Iron (mg/kg) 17 101.8 102.2 1.3 28.8 45.4 89.9 100.0 115.1 165.0
Manganese (mg/kg) 17 32.5 37.6 1.5 13.2 21.2 25.7 38.5 50.0 70.0
Selenium (mg/kg) 17 0.29 0.29 1.9 0.04 0.14 0.30 0.30 0.30 0.30
Zinc (mg/kg) 17 112.9 123.0 1.2 28.3 56.7 108.0 125.0 147.2 165.0
Conditionally essential nutrients
Carnitine (mg/kg) 2 50.0 50.0 NA 0.0 50.0 ND 50.0 ND 50.0
Chromium (mg/kg) 9 0.21 0.20 NA 0.0 0.20 0.20 0.20 0.20 0.22
Cobalt (mg/kg) 1 0.39 0.39 NA ND 0.39 ND 0.39 ND 0.39
Vitamin C (mg/kg) 1 250.0 250.0 NA ND 250.0 ND 250.0 ND 250.0

*   Seventeen producers’ nutritionists provided information for lactation diets, totaling approximately 2,223,600 sows (38.6% of the US sow herd). All reported values are on a complete-feed basis.

†   N indicates the number of producers adding concentrations of a nutrient.

‡   Weighted averages were calculated using the sumproduct function of Excel 2013 (Microsoft) in which the producer supplementation rate was multiplied by the size of the producer (sow herd size). After summing those products they were divided by the total number of sows for all participating producers.

§   Values represent average supplementation rates as a proportion to total dietary vitamin and trace-mineral requirements from the NRC 2012.1

NA = not applicable; NRC1 does not list a requirement for conditionally essential nutrients.

ND = not done; standard deviation (SD) is not meaningful for N of 1, or for the 25th and 75th percentiles for N = 1 or N = 2.

Boar diet information (Table 11) was provided by 13 of the producers. Fat-soluble vitamins were supplemented at rates of 2.8 times vitamin A, 9.3 times vitamin D, 1.8 times vitamin E, and 7.0 times vitamin K requirement estimates. Other vitamins were supplemented at rates of 1.6 times biotin, 0.6 times choline, 1.4 times folic acid, 4.5 times niacin, 2.3 times pantothenic acid, 3.2 times pyridoxine, 2.2 times riboflavin, 2.0 times thiamin, and 3.1 times vitamin B12 requirement estimates. One producer supplemented vitamin C in boar diets at a rate of 250 mg per kg of diet. Trace-mineral supplementation rates were 4.0 times copper, 4.4 times iodine, 1.4 times iron, 2.3 times manganese, 1.0 times selenium, and 2.8 times zinc requirement estimates. One producer supplemented selenium at a concentration (0.42 mg per kg) above the maximum concentration of 0.30 mg per kg, which was due to an increased inclusion rate of a premix that was also used in other diets. Seven producers supplemented chromium at a rate of 0.21 mg per kg, and one producer supplemented cobalt at a rate of 0.39 mg per kg. One producer supplemented carnitine at a rate of 60 mg per kg of diet.

Table 11: Added vitamin and trace-mineral concentrations in boar diets*

N Weighted average Average Ratio to NRC§ SD Low 25% Median 75% High
Fat-soluble vitamins
A (IU/kg) 13 10,549 11,249 2.8 1898 7698 9957 11,000 12,558 15,400
D (IU/kg) 13 1608 847 9.3 442.9 1097 1541 1760 2141 2614
E (IU/kg) 13 72.2 77.4 1.8 31.0 44.0 59.0 66.0 99.0 150.0
K (mg/kg) 13 3.5 3.5 7.0 1.0 1.8 2.6 3.7 4.4 4.8
Other vitamins
Biotin (mg/kg) 13 0.31 0.33 1.6 0.15 0.22 0.22 0.29 0.40 0.64
Choline (mg/kg) 10 637.6 715.7 0.6 507.8 259.8 480.7 584.1 786.1 2079
Folic acid (mg/kg) 13 1.8 1.8 1.4 0.70 1.1 1.3 1.7 2.3 3.5
Niacin (mg/kg) 13 41.4 44.9 4.5 6.6 33.0 41.4 45.1 49.5 55.0
Pantothenic acid (mg/kg) 13 27.7 27.7 2.3 4.2 22.0 25.3 27.5 28.8 37.0
Riboflavin (mg/kg) 13 7.7 8.1 2.2 1.5 5.5 7.5 8.4 9.5 9.9
Thiamin (mg/kg) 5 2.1 2.0 2.0 1.2 0.09 1.1 2.2 2.8 3.3
Vitamin B6 (mg/kg) 10 3.7 3.3 3.2 1.6 0.13 2.2 3.3 4.6 5.1
Vitamin B12 (µg/kg) 13 39.2 46.4 3.1 34.8 27.3 33.0 37.2 44.0 160.8
Trace minerals
Copper (mg/kg) 13 16.6 19.8 4.0 10.6 11.2 13.7 15.1 23.9 46.5
Iodine (mg/kg) 13 0.62 0.61 4.4 0.31 0.22 0.36 0.52 0.71 1.3
Iron (mg/kg) 13 109.6 109.0 1.4 26.9 61.1 90.1 105.8 122.5 165.0
Manganese (mg/kg) 13 35.3 45.1 2.3 22.9 21.2 28.1 38.5 64.9 96.8
Selenium (mg/kg) 13 0.31 0.31 1.0 0.03 0.30 0.30 0.30 0.30 0.42
Zinc (mg/kg) 13 122.3 142.5 2.8 50.5 83.8 112.8 129.8 170.0 279.3
Conditionally essential nutrients
Carnitine (mg/kg) 1 60.0 60.0 NA ND 60.0 ND 60.0 ND 60.0
Chromium (mg/kg) 7 0.21 0.21 NA 0.08 0.20 0.20 0.20 0.20 0.24
Cobalt (mg/kg) 1 0.39 0.39 NA ND 0.39 ND 0.39 ND 0.39
Vitamin C (mg/kg) 1 250.0 250.0 NA ND 250.0 ND 250.0 ND 250.0

*   Thirteen producers’ nutritionists provided information for boar diets, totaling approximately 1,921,100 sows (33.4% of the US sow herd). All reported values are on a complete-feed basis.

†   N indicates the number of producers adding concentrations of a nutrient.

‡   Weighted averages were calculated using the sumproduct function of Excel in which the producer supplementation rate was multiplied by the size of the producer (sow herd size). After summing those products they were divided by the total number of sows for all participating producers.

§   Values represent average supplementation rates as a proportion to total dietary vitamin and trace-mineral requirements from the NRC 2012.1

NA = not applicable; NRC1 does not list a requirement for conditionally essential nutrients.

ND = not done; standard deviation (SD) is not meaningful for N of 1, or for the 25th and 75th percentiles for N = 1 or N = 2.

Nutrient sources

Along with reporting their supplementation rates of vitamins and trace minerals, participants were also asked about the sources of specific nutrients (Table 12) used within the diets. The most distinguishable differences among sources within this survey were associated with supplementation of vitamin D from a cross-linked vitamin AD3 beadlet, potential use of natural (d-alpha-tocopherol) vitamin E as a source of vitamin E, and the use of chelated trace minerals (copper, manganese, selenium, and zinc). For vitamin D3, more than 50% of participants supplemented at least 25% of vitamin D from a vitamin AD3 cross-linked beadlet, across all surveyed diet types. The use of natural (d-alpha-tocopherol) vitamin E as a potential source of vitamin E ranged from 29% to 62% across all surveyed diet types. It is important to note that this question addresses only producers that specifically note natural vitamin E as a possible source when ordering premix from premix blenders. It does not distinguish whether natural vitamin E was used within their premixes or complete diets. Use of chelated sources for partial or complete supplementation of copper, manganese, or zinc ranged from 0% to 46% across surveyed diet types. Chelated selenium for partial or total selenium supplementation ranged from 0% to 77% of respondents across the different diets. Most chelated trace-mineral supplementation occurred in breeding-herd and early-nursery diets.

Table 12: Percentage of participating producers using alternative vitamin and trace-mineral sources*

Participating producers (n) Nursery phase† Finishing‡ Breeding herd
1 2 3 Early Mid Late Ract Gilt dev Gestation Lactation Boar
13 17 18 18 18 18 7 17 17 17 13
Vitamins
AD (%)§ 92 76 67 67 67 67 86 65 65 65 54
E (%)¶ 38 62 56 56 33 33 29 41 41 41 38
Trace minerals**
Copper (%) 15 18 6 0 0 0 0 29 29 29 46
Manganese (%) 15 18 6 0 0 0 0 29 29 29 46
Selenium (%) 69 47 33 6 6 6 0 76 76 76 77
Zinc (%) 15 18 6 0 0 0 0 29 29 29 46

*   A total of 18 swine producers’ nutritionists representing approximately 2,268,900 sows (39.4% of the US sow herd) were surveyed on their supplementation rates of vitamins and trace minerals.

†   Nursery diets consisting of phase 1 (weaning to 7 kg), phase 2 (7 to 11 kg), and phase 3 (11 to 23 kg).

‡   Finishing diets consisting of early-finishing (23 to 55 kg), mid-finishing (55 to 100 kg), late-finishing (100 kg to market), and late-finishing with ractopamine HCl (Ract;100 kg to market). Ractopamine is fed in late-finishing diets at a rate of 5 to 10 g/tonne for improved feed efficiency and gain.

§   Values represent the percentage of producers supplying at least 25% of vitamin D from a vitamin AD3 cross-linked beadlet.

¶   Values represent the percentage of producers that specify natural (d-alpha-tocopherol) vitamin E as a potential source of vitamin E.

**   Values represent the percentage of producers that supplement partial or complete trace-mineral concentrations from chelated sources.

Gilt dev = gilt development.

Discussion

Presumably, the high inclusion rates for copper and zinc reported for some producers were used for growth promotion, as discussed previously by Reese and Hill.7 This led to a large variation in copper and zinc supplementation rates in the nursery phases. In the finishing phase, in general the only vitamin or trace mineral supplemented below the requirement was niacin. It is speculated this may be due to the increase (10 to 30 mg per kg) in niacin requirement from the 19983 to the 2012 NRC1 publication, while the other requirements were unchanged. Again in the finishing phase, similar to the nursery, there was a high ratio relative to the NRC suggestions and a wide variability in copper supplementation rates. Again, we speculate this is due to the use by some producers of high levels for growth promotion versus others that only included concentrations to meet the nutritional requirement. Also, in general, manganese supplementation concentrations were high relative to NRC suggestions in the finishing phases, and we do not have a good explanation for this discrepancy.

Large differences in weight categories were associated with gilt-development diets across the participating production systems. Thus, to standardize the information, the last diet fed before gilts entered the breeding herd was used. Since the NRC does not provide specific requirements for gilt development, the gilt-development diets were compared to NRC1 growing-pig (25 to 50 kg) and gestation requirements. We used these two categories because most recommended vitamin and trace-mineral feeding strategies for developing gilts are similar to those for feeding growing pigs in the early-finisher or gestation diet supplementation rates.

In conclusion, adding a margin of safety for vitamin and trace-mineral supplementation rates over those requirement estimates of NRC1 appear to be standard practice in many US swine diet formulations. However, the degree or range of supplementation varies considerably. We believe this wide variation represents differing opinions on vitamin and trace-mineral requirements and highlights the need for research to examine vitamin and trace-mineral requirements of today’s modern genotypes.

Implications

  • There is variation in vitamin and trace-mineral supplementation rates across the population of respondents within this survey.
  • Although supplementation rates are variable, on the basis of this survey, inclusion of margins of safety for vitamin and trace-mineral supplementation rates appears to be standard practice in US swine diets.
  • This survey provides a baseline for characterization of standard practice for trace-mineral supplementation rates.
  • The variation in vitamin and trace-mineral supplementation observed in this survey will be useful in identifying research needed to determine vitamin and trace-requirements for various phases of production.

Acknowledgement

Contribution no. 16-219-J from the Kansas Agricultural Experimental Station, Manhattan, KS 66506-0210.

Conflict of interest

None reported

Disclaimer

Scientific manuscripts published in the Journal of Swine Health and Production are peer reviewed. However, information on medications, feed, and management techniques may be specific to the research or commercial situation presented in the manuscript. It is the responsibility of the reader to use information responsibly and in accordance with the rules and regulations governing research or the practice of veterinary medicine in their country or region.

References

1. NRC. Nutrient Requirements of Swine. 11th rev ed. Washington, DC; National Academy Press; 2012.

2. Coelho MB, Cousins B. Vitamin supplementation supports higher performance. Feedstuffs. 1997;27:10–12, 20–21.

3. NRC. Nutrient Requirements of Swine. 10th rev ed. Washington, DC; National Academy Press; 1998.

*4. Mahan DC, Hill GM, Gowanlock D, Joliff JS, Samuel RS. A new approach in determining the micro mineral needs of the growing pig. Proc Midwest Swine Nutrition Conf. Indianapolis, Indiana. 2013;9–17.

*5. Successful Farming. Pork Powerhouses 2013: Disease hits, growth continues. Available at http://www.agriculture.com/livestock/hogs/pk-powerhouses-2013-disease-hits-growth_283-ar34203. Accessed 25 August 2016.

*6. USDA. Quarterly Hogs and Pigs. 2013. Available at http://www.thepigsite.com/reports/?id=3265. Accessed 23 June 2016.

7. Reese DE, Hill GM. Trace minerals and vitamins for swine diets. In: Meisinger DJ, ed. National Swine Nutrition Guide. Ames, Iowa: U.S. Pork Center of Excellence; 2010.

* Non-refereed references.