Husbandry practices and gut health outcomes in weaned piglets:A review

The immediate post-weaning period is one of the most stressful phases in a pig's life, and during this period, piglets are usually exposed to environmental, social and psychological stressors which have direct or indirect effects on gut health and overall growth performance. In this review, the impact of husbandry practices on gut health outcomes and performance of piglets is discussed. Husbandry practices in the swine barn generally include nutrition and management practices, maintenance of hygienic standards and disease prevention protocols, and animal welfare considerations. Poor husbandry practices could result in reduced feed intake, stress and disease conditions, and consequently affect gut health and performance in weaned piglets. Reduced feed intake is a major risk factor for impaired gut structure and function and therefore a key goal is to maximize feed intake in newly weaned piglets. In weaned piglets, crowding stress could reduce pig performance, favor the proliferation of pathogenic bacteria resulting in diarrhea, stimulate immune responses and interfere with beneficial microbial activities in the gut. Sanitation conditions in the swine barn plays an important role for optimal piglet performance, because unclean conditions reduced growth performance, shifted nutrient requirements to support the immune system and negatively affected the gut morphology in weaned piglets. Appropriate biosecurity measures need to be designed to prevent disease entry and spread within a swine operation,which in turn helps to keep all pigs and piglets healthy. Collectively, husbandry practices relating to feeding and nutrition, animal welfare, biosecurity and disease prevention are important determinants of gut health and piglet performance. Thus, it is suggested that adopting high husbandry practices is a critical piece in strategies aimed at raising pigs without the use of in-feed antibiotics.

Effects of dietary threonine:lysine ratioes and sanitary conditions on performance, plasma urea nitrogen, plasma-free threonine and lysine of weaned pigs

Two 21 d-experiments were conducted to determine the optimum standardized ileal digestible(SID)threonine:lysine ratio(Thr:Lys) for weaned piglets reared under clean(Exp. 1) or unclean(Exp. 2) sanitary conditions and fed antibiotic-free diets. In each experiment, 90 mixed-sex pigs(Duroc × [Yorkshire × Landrace]; initial BW 7.2 ± 0.3 kg) were randomly assigned to 5 dietary treatments each with 6 replicates(3 pigs per pen). The dietary treatments were 5 graded levels of SID Thr:Lys(55,59, 63, 67 and 71%). Diets were corn-wheat-soybean meal-based with a constant SID Lys of 1.18% that was set to be second limiting amino acid. In Exp. 1 and Exp. 2, plasma-free Thr increased(P = 0.05) with increasing dietary SID Thr:Lys. In Exp. 1, the SID Thr:Lys for gain-to-feed ratio(G:F) was optimized at 65%.In Exp. 2, the estimated optimal SID Thr:Lys for overall G:F was 66.5%. In conclusion, an average optimal SID Thr:Lys of 65 and 66.5% could be used to optimize feed efficiency for weaned pigs under clean and unclean sanitary conditions, respectively.

Effects of derived meals from juncea(Brassica juncea),yellow and black seeded canola(Brassica napus)and multicarbohydrase enzymes supplementation on apparent metabolizable energy in broiler chickens

Two experiments were conducted to determine the nitrogen-corrected apparent metabolizable energy(AMEn) of differently processed meals from Juncea(Brassica juncea), yellow and black seeded canola(Brassica napus), with or without supplementation of multi-carbohydrase enzymes(Enz) in diets for broiler chickens. The first experiment was a 3×2×2 factorial arrangement with the main factors being seed type(yellow [Yellow] or black [B1] canola seeds and Juncea seeds), processed at two temperatures(high temperature desolventized-toasted [HTDT] at 95℃ or low temperature desolventized-toasted[LTDT] at 57℃), with or without Enz. In Exp. 1, a total of 384 one-day-old male broiler chicks were randomly assigned to 64 battery cages, with 6 birds/cage. The second experiment was a 2×2×2 factorial arrangement with the main factors being seed type(Yellow or black [B2]), seed source(Scott,Saskatchewan or Truro, Nova Scotia) and Enz(with or without) supplementation. A total of 264 one-dayold male broiler chicks were randomly assigned to 44 battery cages, with 6 birds per cage. In Exp, 1 and 2,all birds were fed a common starter diet from 1 to 14 days of age. From d 15 to 21, the birds were fed one of the test treatments, a basal grower diet or the basal grower diet replaced with 30% test ingredient with celite(0.8%) added as an inert marker. Excreta was collected on d 20 and 21. In Exp. 1, there were no interactions(P > 0.05) among seed type, processing temperature and Enz. Processing temperature and dietary Enz did not affect(P > 0.05) AMEn of different canola meals. The AMEn of prepress solvent extracted canola and juncea meals(PSEM) from Yellow(11.2 MJ/kg) was higher(P < 0.05) than B1(10.2 MJ/kg) and Juncea(10.2 MJ/kg). In Exp. 2, there were no interactions(P > 0.05) among seed color,location and Enz. Supplementation of dietary Enz did not affect(P > 0.05) AMEn of different cold press canola meals. The AMEn of cold press canola meals(CPM) from Yellow(14.7 MJ/kg) was higher(P < 0.05)compared with B2(12.2 MJ/kg). In conclusion, among the different processing methods of oil extraction,meals derived from yellow seeded canola had higher AMEn than B seeded canola and Juncea.