Effect of Weaning Ages on Pancreatic and Intestinal Chymotrypsin Activity in Piglet

Twelve litters of new born piglets were divided randomly into groups I , I , M and F , and weaned at 17, 21, 28 and 35 days of age, respectively, to determine the effect of weaning age on pancreatic and intestinal chymotrypsin activity in piglets. The results showed that the relative and specific activity of pancreatic chymotrypsin increased significantly 12h after weaning compared with that of sucking piglets at the same age and then decreased and remained low for 2 - 3 weeks after weaning. Total pancreatic chymotrypsin activity had no change with the increase of pancreas weight during day 18 - 50 regardless of weaning (P > 0.05). Chymotrypsin activity of jejunum had the same change as that of pancreas during sulking stage. Jejunum chymotrypin activity decreased in the first week post-weaning in the piglets weaned before day 28, but had no change in groups weaned at 28 or 35 days. The earlier the weaning age, the longer the restoring time. Chymotrypsin activity in jejunum is more sensitive to the effects of weaning age than in duodenum and ileum.

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.

Haematological Traits of Nigerian Indigenous Pig and Its Hybrid (50% Large White ×50 NIP) at Post Weaning Ages

Pigs play a major role in socioeconomic life of the people;it serves as a source of income for rural population and fulfill important role in culture and food security. Fifty-one weaners were randomly selected at 9, 17 and 25 weeks of age for analysis. Blood from the jugular vein of the weaners was taken to the laboratory for analysis. The leaukocyte parameters used for this study were White blood cell count (WBC), Lymphocyte (LYM) count, Neutrophil (NEU) count, Eosinophil (EOS) and Monocyte (MON) count) and Platelet (PLT) count. Data collected on these leaukocyte parameters were subjected to Analysis of Variance (ANOVA) while the means were separated using Duncan’s Multiple Range Test. The results showed that at 9 weeks of age, compared with the female hybrid, the male hybrid had higher PCV, NEU and EOS (33.12% ± 2.73%, 31.00% ± 3.37% and 0.38% ± 0.18% respectively) values, while the female NIP had higher WBC, LYM and MON (24.55 ± 1.09 × 103/μl, 56.00% ± 3.24% and 0.50% ± 0.50%) values respectively. At 17 weeks of age, the male hybrid had higher WBC and NEU (32.18 ± 1.92 × 103/μl and 32.38% ± 3.56%) values while the female had higher PCV, LYM, EOS and MON (42.50% ± 1.50%, 63.00% ± 5.0%, 2.50% ± 2.50% and 4.50% ± 1.50%) values. At 25 weeks of age, the female hybrid had higher values in all the parameters with the exception of NEU and MON where male had higher values. These ages can be used as criteria for selection for immunocompetence in pigs.

Partial Weaning at Six Weeks of Age Reduces Biting among Mink Kits(Neovison Vison)

Recent studies have demonstrated that postponed weaning age from 6 weeks to 8 weeks in mink increases the number of bites among mink kits. Therefore, a series of studies have been conducted in order to quantify effects of weaning age on mortality, number of bites and growth rates in mink kits weaned at 42 and 56 days after birth during two consecutive breeding seasons. Partial weaning of large litters on Day 42 reduced the number of mink kits and litters with bites from an average frequency of 1.6% to 1.0% for kits and 8.1% to 5.1% for litters and increased growth rate of male kits. These results are highly important for ensuring optimal welfare in mink production, and we recommend that partial weaning (dividing) of large litters should be considered in practical mink farming in the future.