23 Protein Source Selection During Choice-Feeding in Nursery Pigs

Abstract Animal by-product feeding practices decrease waste from animal processing and create feedstuffs with favorable nutrient profiles. Including animal proteins has decreased recently due to consumer push to increase vegetarian fed animals. Pigs have demonstrated abilities to choose diets meeting their nutritional requirements when presented with a choice-feeding system (Rose and Kyriazakis, 1991). The objective of this study was to observe nursery pig behaviors in selecting animal and plant protein sources given a choice-feeding system. Pigs (n=72) were housed in groups of nine and given ad libitum access to ground corn, soybean meal (SBM), vitamin premix, ruminant blood meal (RBM), bovine meat and bone meal (BMB), and chicken by-product meal (CBP). Feedstuffs were randomly assigned to feeders and weighed daily. The study was repeated with individually housed pigs (n=8) to compare feeding behaviors. Pigs were weighed at the beginning of the trial with mean weights of 16.83 kg for group and 24.71 kg for individual and end of the trial with mean weights of 24.25 kg for group and 34.90 kg for individual. No intake differences were seen between housing treatment (P >0.05). Protein source intake differed (P< 0.0001), with CBP having the greatest consumption followed by SBM. A second trial (n=30) was conducted to determine preference when protein sources were mixed into corn-soy based diets and given ad libitum in a choice-feeding system for both groups of four (n=24) and individually housed pigs (n=6); starting mean weights of 14.83 kg and ending weights of 21.14 kg. Preference did not differ between housing or pen (P >0.05) showing no feeder preferences or diet preference (P=0.9997). Data concludes that pigs preferentially select animal by-products as part of their diet when presented with a choice-feeding system. Nursery pigs do not have a preference when choosing from diets.