Animal Bioscience最新文献

Objective: To investigate the use of cassava stems as an alternative feedstuff for ruminants, a study was conducted measuring the effect of replacing rice straw with untreated and treated dried cassava stems. The study assessed its impact on feed intake, nutrient digestibility, blood metabolites, and the growth performance of Thai native cattle.

Methods: Six male cattle were arranged in a 3x3 replicated Latin square design to receive three treatments. All animals were provided with rice straw ad libitum and 14% CP concentrate at 0.5% BW. Treatment variations consisted of a control group (Ctrl), one group that replaced rice straw with dried cassava stem (DCS), and another group that replaced rice straw with alkali, urea, and Ca(OH)2, treated dried cassava stem (tDCS) at 15% of rice straw intake. The experiment spanned three 21-day periods.

Results: Feed intake, body weight gain, and FCR were similar across treatments. Total tract apparent digestibility for the cattle, which included DM, OM, CP, NDF, and ADF, was higher than those on the tDCS treatment compared to the other groups (p<0.05). Ruminal pH, volatile fatty acid concentration, and blood metabolites remained unaffected by dietary treatments, except for BUN which was increased with tDCS replaced rice straw (p<0.05). Alkali-treated DCS helped reduce rectum temperature compared to the control and DCS group (p<0.05).

Conclusion: Replacing rice straw with tDCS improved nutrient digestibility but did not significantly impact feed intake, growth rate, FCR, rumen fermentation, and the blood metabolite of Thai native cattle.

Objective: The objective of this research was to explore the changes of morphological parameters, short chain fatty acid contents and butyric acid transporter expression levels in the large intestine with growth and development of sucking lambs.

Methods: A total of 48 newborn male Hu sheep lambs (body weight = 2.94 ± 0.22 kg) were selected in this experiment. At 0, 7, 14, 28 and 42 days of ages, 6 lambs were slaughtered to collect cecal and colonic samples to analyze morphological parameters, short chain fatty acid contents and butyric acid transporter mRNA expression.

Results: The organ index of the cecum in d 0, 28 and 42 groups was higher (p<0.05) than that in d 7 and 14 groups. Compared with other age groups, the organ index of the colon was significantly increased (p<0.05) at d 42 group. After 7 days of age, the contents of acetic, propionic and butyric acids in the cecum and colon were significantly increased (p<0.05) as age increasing. A similar trend of mRNA expressions of butyric acid transporters, including monocarboxylate transporter, sodium-coupled monocarboxylate transporter, sodium-hydrogen exchanger, down regulated in adenoma, putative anion transporter-1 and anion exchanger-2, was found. In the cecum, the Escherichia coli count in d 14 group was higher (p<0.05) than that in other age groups, whereas an opposite tendency was found in Lactobacillus count between d 14 and other groups. Additionally, in the cecum and colon, the relative expression of claudin-1 in d 14 group was lower (p<0.05) that in d 42 group.

Conclusion: Overall, the current results indicate that the expression levels of butyric acid transporters in the cecum and colon of lambs are significantly influenced by days of age.

Objective: We aimed to investigate the impacts of nitrate and nitrite on the salami fermentation process.

Methods: Experimental groups of dry-fermented sausage were prepared with 100 ppm nitrite (T1), 150 ppm nitrite (T2), and 100 ppm nitrite + 50 ppm nitrate (T3). Salami quality was evaluated after a 30-day fermentation-drying process.

Results: There were no significant differences in residual nitrite levels between T1 and T2, while the T3 samples exhibited the highest residual nitrite. T2 (150 ppm nitrite) showed a significantly higher pH value compared to T1 (100 ppm nitrite). Water activity was lowest in the T2 sample. T1 had a higher TBARS value than other treatments. In the color analysis, the L* values of T1 and T2 were significantly higher than those of T3, whereas the a* values were significantly higher in T3. In the texture analysis, T3 exhibited a higher shear force than T1 and T2. In the microbial analysis, adding 50 and 100 ppm of nitrite did not reduce the total plate count (TPC) and lactic acid bacteria count. However, T3 had a lower TPC than T1 and T2.

Conclusion: The results suggest that different levels of nitrite/nitrate affect salami quality. This study is a valuable resource for understanding how using nitrite and nitrate alone or in combination affects quality in salami production.

Objective: Subclinical hypocalcemia induces metabolic stress, which adversely affects the production performance of peripartal dairy goats. This study sought to uncover new aspects of disease prevention and control by applying metabolomics and lipidomics to identify key differences in metabolite expression between affected and healthy animals.

Methods: This study collected plasma samples from 96 primiparous Guanzhong dairy goats with similar body condition scores (2.75 ± 0.15, mean ± standard deviation) on the day of calving, aiming to uncover new aspects of disease prevention and control by applying metabolomics and lipidomics to identify key differences in metabolite expression between affected and healthy animals.

Results: The study identified 23 differential metabolites and 30 differentially altered lipids involved in various metabolic pathways, such as phenylalanine and tyrosine metabolism, aminoacyl-tRNA biosynthesis, and glycerophospholipid metabolism. Our research revealed significant differences in the regulation of calcium-related hormones and associated metabolites between subclinical hypocalcemic and healthy dairy goats. Specifically, we found a positive correlation between parathyroid hormone (PTH) and aspartate aminotransferase (AST) in the healthy group, contrasting with a negative correlation observed in the subclinical hypocalcemic group.

Conclusion: Additionally, phenylalanine and phosphatidylserine were identified as potential biomarkers indicative of subclinical hypocalcemia. These findings offer a novel approach to managing subclinical hypocalcemia in dairy goats, potentially transforming prevention and control strategies in the dairy goat industry.

Objective: Hot environments negatively affect cattle productivity, and global warming also causes heat stress, thereby adversely impacting cattle production. Improving cattle management under such conditions is an urgent issue. Trehalose can ameliorate volatile fatty acid production and the diversity of ruminal microbiota in dairy cattle. However, no studies have evaluated on Japanese beef heifers. In this study, we investigated the effects of trehalose supplementation on the ruminal microbiota and productivity of Japanese Black heifers under heat-stressed conditions.

Methods: Six cyclic Japanese Black heifers were divided into two groups: control and trehalose supplemented. The ruminal microbiota, pH, and volatile fatty acid production of these heifers were analyzed over 10 weeks in the summer in central Japan.

Results: During the experimental period, the heifers in the control group showed significantly higher concentrations of ruminal acetic and propionic acids than those in the trehalose-supplemented group (p<0.05, two-way repeated measures ANOVA). The acetic/propionic acid ratio showed no significant difference between the two groups. The alpha diversity in the ruminal bacterial biota in the trehalose supplemented group was higher than that in the control group (p<0.05, two-way repeated measures ANOVA) along with a change in the beta diversity of the ruminal fungal biota (p<0.05, PERMANOVA). LEfSe analysis in ruminal microbiota identified specific microorganisms in the control and the trehalose-supplemented samples: 4 and 13 in bacteria; each one fungus; 5 and 4 protozoan families, respectively.

Conclusion: Trehalose supplementation in the summer improved ruminal microbiota, especially the types of ruminal bacteria and fungi related to carbohydrate digestion, and maintained the balance of ruminal VFA production in Japanese Black heifers. Therefore, trehalose supplementation in feed could improve cattle production under heat-stressed conditions and in global-warming scenarios.

Objective: The rice-duck-crayfish (RDC) coculture system, an ecologically efficient breeding method, supports ducks' natural habits and enhances duck welfare. However, the optimal stocking density and its influence on duck health in this system remains undetermined. The study examined the effects of stocking densities on growth, organ index, serum biochemistry, gut morphology and microbiota of ducks in RDC system.

Methods: A total of five hundred and forty 20-day-old Nonghu No. 2 ducks were randomly divided into low-density (8 birds/666.67 m2, LD), medium-density (12 birds/666.67 m2, MD) and high-density (16 birds/666.67 m2, HD) groups, with three replicates in each group, and the symbiosis period was up to 40 days until rice tasselling.

Results: There were no significant differences in final body weight, average daily gain, or feed:gain ratio between groups (p>0.05); the liver and spleen indices of ducks in HD group were significantly greater than in LD group (p<0.05); the serum albumin concentration in HD group decreased, whereas creatine kinase activity increased (p<0.05); the ileal crypt depth significantly increased; and the ileal villus height and villus/crypt ratio significantly decreased in ducks in MD and HD groups than in LD group (p<0.05). Additionally, the abundance of cecal Deferribacterota and Spirochaetota increased significantly (p<0.05), while the abundance of Firmicutes decreased significantly (p<0.05) with increasing stocking density. Moreover, the increase in stocking density significantly decreased the abundance of some beneficial bacteria (Faecalibacterium and Fournierella) and increased the abundance of some harmful bacteria (Mucispirillum and Brachyspira) (p<0.05).

Conclusion: These preliminary results suggest that moderately high-density breeding doesn't significantly affect duck growth, but increased stocking density led to changes in cecal microbiota and dysbiosis. Reducing stocking density positively affects immune parameters and ileum morphology.However, due to the limited number of total replicates of the study, further research is needed to validate the reliability of the results.

Objective: Improving fertility is a key goal in goat production. This study aimed to detect single nucleotide polymorphisms (SNPs) associated with female goat reproductive performance for use in selection processes.

Methods: Nine reproductive traits were evaluated, including litter size and age at the first, second, and third parities, as well as intervals between parities, in 31 female goats (2 purebred and 29 crossbred goats in various combinations of seven breeds). DNA was extracted from blood, and SNP data were obtained using the genotyping by sequencing (GBS) method. After filtering for allele depth and missing genotype data, the retained SNPs were subjected to population structure analysis and association analysis with the nine traits. For the association analysis, SNPs with false discovery rates ≤ 0.05 were considered significant. PCR allele competitive extension (PACE) genotyping assay was applied to develop genetic markers.

Results: An average of 304,852 SNPs were initially detected in the 31 female goats. After filtering, 21,665 SNPs were retained. The first two principal components obtained from individual genotypes classified the 31 goats into three clusters. In the association analysis, six SNPs on four chromosomes were significantly associated with the litter size at first parity. The most significant SNP was detected on chromosome 4, and three genes-IKAROS family zinc finger 1 (IKZF1), fidgetin-like 1 (FIGNL1), and dopa decarboxylase (DDC)-were found within 100 kb downstream and upstream of the SNP. The PACE genotyping assay confirmed genotypes at this SNP with a 96% concordance rate.

Conclusion: SNPs significantly associated with litter size at first parity, candidate genes, and the PACE genotyping methods applied in this study can be used for selecting female goats in future genetic improvement programs. However, further study on the frequency of genetic mutation with a larger sample size and functional studies of the candidate genes are required.

Objective: This study aimed to identify polymorphisms in the gene encoding the 3-hydroxy-3-methylglutaryl-CoA synthase 1, HMGCS1, and analyze their association with slaughter characteristics, meat quality, and organ coefficients in Guizhou white goats.

Methods: A total of 153 twelve-month-old Guizhou white goats (78 male and 75 female) were included in the study. Slaughter characteristics, meat quality, and organ coefficients were assessed. Association analyses between genotypes and phenotypic traits were conducted using a generalized linear model.

Results: Four polymorphic loci were identified, i.e., g.15523T>C, g.15530G>C, g.18413T>C, g.19711G>A in exons 5, 8, and 9 of the HMGCS1 gene. Across all polymorphic loci, males of the same genotype generally exhibited significantly better slaughter traits compared to females of the same genotype (p < 0.05). At the g.18413T>C locus, differences in shear force were observed between males and females of the same genotype and within the same sex across different genotypes (p < 0.05). Organ coefficients were significantly higher in males of the same genotype compared to females (p < 0.05). The g.15523T>C and g.15530G>C loci were found in strong linkage disequilibrium and significantly associated with intramuscular fat content (p < 0.05). Fat content in diploid Hap2/2 individuals was significantly higher than in Hap1/1 and Hap1/2 (p < 0.05). At the g.19711G>A locus, female goats with the CC genotype showed significantly higher levels of dry matter compared to male goats of the same genotype and female goats of other genotypes within the group. Organ coefficients for the liver and hooves in male goats were significantly higher than in females of the same genotype (p < 0.05).

Conclusion: The strongly linked loci g.15523T>C and g.15530G>C were significantly associated with intramuscular fat content and could be used as molecular markers for enhancing this trait in goat breeding programs, fostering the development of goat production.

Objective: Pregnancy in cattle after embryo transfer (ET) is influenced by several factors, including embryo quality. Therefore, preparing high-quality embryos with the greatest developmental potential is essential for achieving a successful pregnancy after ET. Meanwhile, blastocysts produced by in vitro fertilization (IVF) procedure have different developmental speed during in vitro culture (IVC) and they exhibited different competence in the establishment of pregnancy.

Methods: This study aimed to identify the comparative features of early-, mid-, and late-developing bovine IVF blastocysts, when they first appeared at Day 7, 8, and 9 during IVC, respectively. In addition, the correlations between their molecular features and pregnancy ability were analyzed.

Results: The results showed no difference in the morphological characteristics, including total cell count and diameter, between the Day 7, 8, and 9 blastocysts. However, the pregnancy rate post-ET was significantly different between the groups at 51.7%, 36.7%, and 17.8% for Day 7, 8, and 9 blastocysts, respectively. During early embryo development, late-developing blastocysts demonstrated a reduced cell count in the inner cell mass and decreased expression of the early embryo developmental genes (Oct4 and Sox2) compared with the early- and mid-developing blastocysts. In addition, the number of apoptotic cells and apoptosis-related gene expression (increased Bax and decreased Bcl2) gradually elevated from the Day 7 to Day 9 blastocysts. However, there was no difference in mitochondrial activity and mitochondria-relevant gene expression (Tfam and Cox1) between the groups. Correlation analysis identified a significantly negative correlation between the pregnancy rate and the blastocysts' degree of apoptosis, indicating that the low pregnancy ability of late-developing blastocysts was mainly caused by increased apoptosis.

Conclusion: This study's results may contribute to the field of animal biotechnology by assisting in establishing an improved strategy for bovine ET with IVF embryos.

Objective: To investigate genetic correlation between calving ease (CE) and gestation length (GL) traits of Korean Holstein cattle to understand genetic structures of these two traits and their potential implications.

Methods: Records of progenies from first parity (P1, N=117,921) and second parity (P2, N=141,104) Holsteins cows were used for analysis. All phenotypes (CE and GL) were considered as calf traits. The CE was an ordered categorical trait. It was scored from 1 (normal calving) to 4 (difficult calving). GL observations were restricted between 260 and 305 days. Variance components and genetic parameters were estimated through a bivariate animal model with a correlated maternal effect using the BLUPF90+ software package.

Results: Heritability (h2) estimates of CE for direct and maternal effects were low (less than 0.01) in all parity calves. For GL, despite lower h2 of maternal effect (~0.03), the direct effect was moderately heritable (0.20 to 0.23) in this study. Direct and maternal effects of CE trait were weakly correlated (P1: 0.09 ± 16.60, P2: -0.04 ± 0.00). GL had similar correlation patterns (P1: 0.03 ± 0.00; P2: -0.15 ± 0.05) across parities. Direct genetic correlations of GL and CE were mostly weak (P1: 0.18 ± 0.31; P2: -0.01 ± 0.06), whereas maternal genetic correlations were moderate and positive (P1: 0.39 ± 0.95; P2: 0.46 ± 0.04). Although the genetic influence of GL on CE was not entirely clear due to large estimation errors for parameters, overall positive associations between direct effects and maternal effects essentially indicate a selection potential for GL as an indicator trait of CE.

Conclusion: This is the first genetic correlation investigation of GL and CE in Korean Holstein cattle. It provides important insights into genetic architectures of GL and its future potential as an indicator trait for CE improvements in Korean Holsteins.