Research Accomplishment Reports 2011

Nutritional Systems For Swine To Increase Reproductive Efficiency

M.D. Lindemann, D.K. Aaron
Department of Animal and Food Sciences

 

Non-Technical Summary

A primary factor affecting profitability of swine enterprises is sow productivity and optimum nutrition of the sow is essential to maximizing productivity. However, the potential impact of nutrient pollution of the environment is probably the major issue facing swine producers. A primary factor affecting profitability of swine enterprises is sow productivity and optimum nutrition of the sow is essential to maximizing productivity. However, the potential impact of nutrient pollution of the environment is probably the major issue facing swine producers.

2011 Project Description

1. Previous studies clearly defined the ratio of the amino acid tryptophan that is needed in the diet to the amino acid lysine when pigs are fed in U.S.-type situations. These results were reported and will help limit the amount of unnecessary supplementation of tryptophan to swine diets which will reduce total dietary cost and will reduce nitrogen excretion by pigs. We have finished the analysis of three studies that determined if the exposure of pigs to antibiotics in the diet affected the ideal tryptophan/lysine ratio. The results will be prepared for presentation at scientific meetings.

2. A study was conducted with nursery pigs to determine the impact of dietary mycotoxins on diet digestibility. Many previous studies have examined the effect of mycotoxins on growth rate and feed efficiency of pigs. In general, the occurrence of mycotoxins in feed is associated with reduced feed intake and, consequently, reduced growth; because of these reductions there is often a reduction in whole body feed/gain ratio. But the directly measured effects on diet digestibility have not been made. Our work compared 2009 crop year corn with 2010 crop year corn as the base for a nursery diet (the 2009 crop year corn had low levels of 2-3 mycotoxins and was a challenge for producers in much of the Midwest); we also compared a diet with a 50:50 blend of those corns for an intermediate treatment. We measured the effect on digestibility of dry matter, energy, and crude protein. We also conducted a preference study in which pigs were given access to 2 feeders which contained 2 of those 3 diets to see if pigs could discriminate between the diets (either by olfaction or taste) and would demonstrate a preference for either of the diets available to them. The results are being prepared for presentation at a scientific meeting and will be submitted to trade magazines.

3. A study was initiated to evaluate the vitamin K need of reproducing swine. There are no reported studies that have evaluated this vitamin for reproduction in swine. We fed pigs from weaning to market weight on diets with 3 levels of vitamin K (no added K, K at the NRC requirement estimate, and K at 4X the requirement estimate). Females were retained from that study and will be continued on that level of supplementation throughout 2 parities. Females will be bred in early 2012 and will then take 1 year to complete the study.

4. A study has been initiated to evaluate the vitamin D status of nursery pigs. Current industry evaluations by veterinarians are indicating a very low vitamin D status at weaning and throughout the nursery phase for pigs. This is associated with varying degrees of death loss in the piglets. We are evaluating the vitamin D status at birth, weaning, and 2-4 weeks post-weaning of young piglets. We are evaluating, also, their response to various oral and injectable forms of vitamin D supplementation. Results will eventually presented at veterinary professional meetings.

2011 Impact

1. Our work will be the first that examines the effect of an antibiotic on amino acid requirements in pigs. The studies were undertaken because much of Europe does not utilize antibiotics and they recommend a much higher ratio. As US producers transition away from antibiotics, they need to know if additional tryptophan is needed in diets to allow maximal rate of gain and lean tissue deposition in pigs. The results clearly indicate that additional tryptophan is not needed in swine diets when antibiotics are removed. These results allow producers and society greater information for clarity of the impact of the potential removal of antibiotics as a production tool on the health as well as the nutritional needs of the pigs themselves.

2. The occurrence of mycotoxins in feedstuffs depends on geography, crop being grown, planting date, and weather, among other factors. They are, therefore, a relatively common problem each year in some part of the US. In some years they are a universal problem and the effects on animal production are magnified both in incidence and degree of the problem. While it is universally known that the solution to the problem is to purchase non-contaminated grains, that option is not always available. When it is not available, the producer must know the full extent of the biological impact of those toxins in order to mitigate the adverse effects.

Our results clearly show that the pig can discriminate between diets that contain toxins and will choose the noncontaminated diet when given the choice. Upon final analysis of our digestibility results, we will be able to make recommendations of useful dietary nutrient alterations to maintain nutrient absorption when contaminated diets must be fed.

3. In the growing animal, when vitamin K is inadequate there are problems with blood clotting and, sometimes, bone development. Studies have never been reported that evaluated this vitamin for reproduction in swine. While there is not any concern about bleeding problems in mature or newborn swine, nor any impression of bone problems, the fact that this has never been evaluated leaves the possibility that swine are not being fed in a manner that optimizes health and well being. Our study will provide evidence whether there is need for additional research in the reproducing animal or whether the current lack of focus on the vitamin is acceptable.

4. When the initial work on vitamin D (the "sunshine" vitamin), the pigs usually had periods of their life in which they were outside or had access (via windows) to sunshine. Modern production utilizes many buildings that do not have windows and pigs are sometimes produced in an environment in which they have no access to direct sunlight for their entire life. Vitamin D is a relatively inexpensive vitamin and many veterinarians in the Midwest are now advocating oral or injectable supplementation of the young pig. However, there is not adequate data upon which to make this recommendation for producers. Our study will provide the first results that illustrate the normal plasma vitamin D status from birth to 8 weeks of age and how it can be moderated by a variety of supplemental vitamin D products.

2011 Publications

Quant, A. D., M. D. Lindemann, B. J. Kerr, R. L. Payne, and G. L. Cromwell. 2011. Standardized ileal digestible tryptophan to lysine ratios in growing pigs fed corn-based and non-corn-based diets. J. Anim. Sci.; published ahead of print November 11, 2011, doi:10.2527/jas.2011-4537.

Ma, Y. L., M. D. Lindemann, G. L. Cromwell, R. B. Cox, G. Rentfrow and J. L. Pierce. 2011. Evaluation of trace mineral source and pre-slaughter deletion of those minerals on performance, carcass characteristics, and pork quality in pigs. J. Anim. Sci. (accepted; in editorial revision).

Ma, Y. L., M. D. Lindemann1, J. M. Unrine, J. L. Pierce, and G. L. Cromwell. 2011. Nutrients changes in fetal and maternal tissues of gilts fed organic selenium during gestation. J. Anim. Sci. Vol. 89, E-Suppl. 2:105.