Animal Science Journal最新文献

Heat stress negatively affects the reproductive function of in animals and humans. Although a relationship between heat and oxidative stress has been suggested, the underlying mechanism has not been sufficiently examined in reproduction-related cells. Therefore, we aimed to investigate whether heat stress induces oxidative stress using a variety of reproduction-related cells including bovine placental and cumulus–granulosa cells, human cell lines derived from cervical and endometrial cancers, and fibroblasts derived from endometrium. Quantitative polymerase chain reaction analysis showed that the expression levels of representative heat and oxidative stress–related genes were significantly increased in cells cultured at high temperatures compared with those in cells cultured at basal temperatures. Moreover, luciferase reporter assays showed that the reporter activity of the heat shock element and antioxidant responsive element (ARE) was increased in cells cultured at high temperatures compared with that in cells cultured at basal temperatures. Furthermore, the stability of nuclear factor erythroid 2 like 2 (NFE2L2), a master regulator of the cellular stress response, increased under high temperatures. Point mutations in Kelch-like ECH-associated protein 1 (KEAP1) cysteine residues reduced the luciferase activity. Our results suggest that heat stress induces oxidative stress and that the KEAP1-NFE2L2-ARE pathway may play a protective role in reproduction-related cells against heat stress.

The aim of this study was to investigate changes in milk conditions and antimicrobial components in goats during 8 weeks prepartum and 1 week postpartum. Milk was collected weekly from seven prepartum goats 8 weeks before the due day, immediately, and 1 week after parturition. Milk color scores and the concentration of antimicrobial components (cathelicidin-7 and S100A8) were significantly increased prepartum. There was a significant decrease in milk viscosity, color scores, somatic cell count, and antimicrobial components (lactoferrin and cathelicidin-2, 7) after kidding. However, S100A7 levels did not change throughout the prepartum or postpartum periods. These results indicate that concentrations of cathelicidin-7 and S100A8 differ between prepartum and postpartum periods. Therefore, these microbial components may play different roles in mastitis prevention. The findings of our study provide important information for regulating antimicrobial components in ruminants to prevent bacterial invasion during the peripartum period.

The relationships between the distribution and heritability of a ratio trait and the genetic parameters of its component traits were clarified using a Monte Carlo computer simulation. The component traits of a ratio trait were assumed to be normally distributed. The genetic parameters of the ratio trait were estimated using parent–offspring regression. As the genetic and environmental correlations ($��r_G�$ and $��r_E�$) of the component traits increased, the variance, skewness, and kurtosis of the ratio trait decreased. The amount of decrease had a greater effect on $��r_E�$ than on $��r_G�$. The estimated heritability of the ratio trait decreased as $��r_G�$ increased and as $��r_E�$ decreased. The estimated heritability of a ratio trait can be higher than the heritability of any of its component traits.

Weaning is essential for foal growth and development. We determined the intestinal flora structure of donkey foals at the end of weaning (PreW_4d) and three stages after weaning (PostW_4d, PostW_8d, and PostW_15d) to explore the effects of weaning on intestinal development of donkey foals. The results showed that the main microbial flora in the gut of the donkey foal were Firmicutes and Bacteroides, and the proportion of Firmicutes gradually increased with weaning, which was an important reflection of the donkey foal's adaptability to the transition from lactose liquid feed to plant fiber solid feed. We also identified important microorganisms that maintain intestinal stability and boost immune, such as oscillospiraceae, Firmicutes, and lachnospiraceae. The metabolome showed that serum metabolites were mainly enriched in arachidonic acid metabolism and the tricarboxylic acid cycle (TCA cycle), which can influence energy metabolism, growth, and immunity in weaned donkey foals. We also found that the metabolite resveratrol was positively correlated with g_NK4A214_group and lactobacillus, which may have important implications for the prevention of diseases such as colon-inflammation in donkey foals. In summary, we provide a theoretical basis for studying the mechanism of intestinal microbiome and serum metabolite changes in weaning and postweaning donkey foals.

This study aims to evaluate the relationship between mineral digestibility and fecal characteristics and compare digestibility in dry and late-lactating cows. A total of 107 multiparous Holstein and Simmental cows were included, with 66 cows in late lactation and 41 cows in the dry period. The apparent digestibility of key macro minerals, dry matter content in feces, dirtiness scores, fecal characteristics, and serum macro mineral levels were determined. Cows consuming the same diet were arranged according to a completely randomized design. Results showed that, compared to the late lactation group, the dry period group had a significantly lower total dirtiness score, higher phosphorus digestibility, and elevated serum calcium levels (p < 0.05). Additionally, fecal consistency and fecal height were greater in the dry period group (p < 0.05). However, the increased phosphorus digestibility observed during the dry period was not significantly associated with fecal consistency (r = +0.225, p < 0.05) or the total contamination score (r = −0.339, p < 0.05). Consequently, this study reveals that understanding the differences in mineral digestibility between different physiological stages can enhance nutritional approaches for better dairy cow management.

The Citri Reticulatae Pericarpium (CRP), is the aged peel of Citrus fruit, which contains phenols, flavonoids, and polysaccharides. This study aims to investigate dietary CRP supplementation on the growth performance, serum biochemical indices, meat quality, intestinal morphology, microbiota, and metabolite of yellow-feathered broilers. A total of 240 yellow-feathered broilers (1.00 ± 0.22 kg, 9 weeks old) were randomly allotted into 4 treatments feeding a basal diet (control), the basal diet containing antibiotics (positive control), and the control diet containing 1.5% and 3% CRP, respectively. At the end of a 56-day trial, one broiler from each replicate was selected, and samples of ileal tissue and cecal digesta were collected to analyze intestinal morphology, microbial composition, and metabolites. The results revealed that 3% CRP decreased average daily feed intake (ADFI), serum total cholesterol (TC), and low-density lipoprotein (LDL). The CRP supplementation could increase serum superoxide dismutase (SOD) and meat pH. Broilers fed CRP had elevated antioxidant and liquid-regulated metabolites. Together, the results suggested that incorporating a moderate level of CRP has a minor impact on growth performance and could benefit health to some extent by enhancing antioxidants, regulating serum liquid, and changing microbial composition and metabolites.