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.

Application of Whey Permeate Fermented with Kefir Grains for the Shelf-Life Improvement of Food and Feed

Fungal contamination by Aspergillus parasiticus and A. flavus causes negative effects on the production of food cereals. Kefir is an ancient fermented beverage obtained by the fermentation of different substrates with kefir grains. An important waste produced by the dairy cheese industry is the whey permeate, which nowadays is a strong ambient contaminant. The aim of this work was the standardization of the whey permeate fermenting conditions with kefir grains, the assessment of the antifungal activity of the cell-free-supernatants (CFS) from these fermentations and to compare it with that obtained with CFS of milk fermented with kefir grains. Finally, we studied if the addition of kefir fermented whey permeate to food (bread) and feed (poultry) could produce shelf life improvement. The optimal condition to obtain CFS with fungicidal effect was a fermentation with 10% w/v of kefir grains, at 30°C, for 24 hours until a pH 3.7. We found that CFS from whey permeate caused fungal inhibition, whereas CFS of kefir grains grown in milk showed lower antifungal activity. Additionally, the addition of kefir-fermented whey permeates in food (bread) and feed (poultry) improved their resistance to fungal contamination. This is the first report about the application of kefir-fermented whey permeate to improve the shelf life, suggesting its potential use as a biopreservative.