Role of milk carbohydrates in intestinal health of nursery pigs: a review

Intestinal health is essential for the resistance to enteric diseases and for nutrient digestion and absorption to support growth.The intestine of nursery pigs are immature and vulnerable to external challenges,which cause negative impacts on the structure and function of the intestine.Among nutritional interventions,the benefits of milk are significant for the intestinal health of pigs.Milk coproducts have traditionally been used in starter feeds to improve the growth of nursery pigs,but their use is somewhat limited due to the high costs and potential risks of excessive lactose on the intestine.Thus,understanding a proper feeding level of milk carbohydrates is an important start of the feeding strategy.For nursery pigs,lactose is considered a highly digestible energy source compared with plant-based starch,whereas milk oligosaccharides are considered bioactive compounds modulating intestinal immunity and microbiota.Therefore,milk carbohydrates,mainly composed of lactose and oligosaccharides,have essential roles in the intestinal development and functions of nursery pigs.The proper feeding levels of lactose in starter feeds could be variable by weaning age,body weight,or genetic lines.Effects of lactose and milk oligosaccharides have been broadly studied in human health and animal production.Therefore,this review focuses on the mechanisms of lactose and milk oligosaccharides affecting intestinal maturation and functions through modulation of enterocyte proliferation,intestinal immunity,and intestinal microbiota of nursery pigs.

Impacts of weaning age on dietary needs of whey permeate for pigs at 7 to 11 kg body weight

Background:Whey permeate is an effective lactose source for nursery pigs and the most benefits are obtained when pigs are at 7 to 11 kg BW.Altering weaning ages could cause different length of early-weaner phases until 7 kg BW and thus it would influence the dietary need of whey permeate during 7 to 11 kg BW of pigs.This study aimed to evaluate if weaning ages would affect the dietary needs of whey permeate for optimum growth performance of pigs at 7 to 11 kg BW.Methods:A total of 1,632 pigs were weaned at d 21(d 21.2±1.3)or d 25(d 24.6±1.1)after birth.All pigs had a common early-weaner feeds until they reached 7 kg BW.When pigs reached 7 kg BW within a weaning age group,they were allotted in a randomized complete block design(2×4 factorial).Two factors were weaning age groups(21 and 25 d of age)and varying whey permeate levels(7.50%,11.25%,15.00%,and 18.75%).Data were analyzed using the GLM and NLIN procedures of SAS for slope-ratio and broken-line analyses to determine the growth response to whey permeate and optimal daily whey permeate intake for the growth of the pigs weaned at different ages.Results:Pigs weaned at 21 d of age had a common diet for 11 d to reach 7 kg BW whereas pigs weaned at 25 d of age needed 2 d.The G:F of pigs weaned at 25 d of age responded to increased daily whey permeate intake greater(P<0.05)than pigs weaned at 21 d of age.Breakpoints were obtained(P<0.05)at 88 and 60 g/d daily whey permeate intake or 17.0%and 14.4%of whey permeate for G:F of pigs weaned at 21 and 25 d of age,respectively.Conclusion:Pigs weaned at an older age with a short early-weaner phase had a greater growth response to whey permeate intake compared with pigs weaned at a younger age with a long early-weaner phase.Altering weaning ages affected dietary needs of whey permeate for optimum growth performance of pigs from 7 to 11 kg BW.