Animal Bioscience最新文献

Objective: This study aimed to assess the impact of a prolonged photoperiod on the growth performance and lipid metabolism of weaned piglets.

Methods: Twenty-four piglets weaned at 28 days of age were randomly dichotomized into two groups that were alternatively subjected to either long photoperiod (LP) group (16L:8D) or short photoperiod (SP) group (10L:14D) for 42days. Four replicates of three animals per replicates were used per experimental treatment.

Results: Our results demonstrated that prolonged photoperiod increased piglet body weight, average daily weight gain (ADG), backfat thickness (BF), backfat index during the nursery period, and increased ADG, average daily feed intake (ADFI), and decreased the F/G of piglets during the experiment days 29 to 42. Meanwhile, we observed LP piglets' plasma melatonin, growth hormone and serotonin levels were decreased at 14 d and 42 d compared to SP piglets. Moreover, up-regulated mRNA or protein expression of PPARγ and CEBPα, and lower mRNA or protein expression of MTR1, ATGL, HSL, PPARα, and CPT1α, were observed in back subcutaneous fat (BSF) of LP group compared with that of SP group. Significant increases were observed in the mRNA or protein contents of lipogenic genes, including C/EBPα, SREBP-1c, ACCα, and FAS, in the liver of LP piglets, whereas CPT1α and ACOX1 mRNA levels and PPARα and MTR1 protein expression were significantly down-regulated in LP group compared to SP group. Extended photoperiod also increased lipid content in longissimus dorsi muscle (LDM) that was associated with higher mRNA or protein levels of SREBP-1c, ACCα, FAS, Pref1, and LPL, decreased mRNA or protein contents of LeptinR, MTR1, HSL, and ACOX1.

Conclusion: Together, these findings suggest that there is an advantage, in terms of growth performance and fat deposition, in imposing a prolonged light program (16-h light/day) on nursery piglets to alleviate the negative aspects of weaning stress.

Objective: This study evaluates the collaborative effect of exogenous enzyme blend and dietary nutrient density on the performance of broiler chicken.

Methods: A total of 600 Ross 308 broiler chickens with same average initial body weight were randomly assigned to 5 treatments. Each treatment contained 8 replicates, and 15 birds per replicate. The diets included a control (CON) starter/finisher (S/F) diet with metabolizable energy (ME) 3,100/3,200 in Kcal/kg and crude protein (CP) content 22.0.0/20.00 in % as (S/F 3,100/3,200 Kcal/kg + CP, 22.00/20.00 %). S/F with ME 3,060/3,150 Kcal/kg + CP 21.50/19.50 % with and without the exogenous enzyme blend as (S/F 3,060/3,150 Kcal/kg + 21.50/19.50 % with, and without the exogenous enzyme blend), and lastly, S/F with ME 3,010/3,100 Kcal/kg + CP 21.50/19.50 % with, and without the exogenous enzyme blend as (S/F 3,010/3,100 Kcal/kg + 21.50/19.50 % with, and without the exogenous enzyme blend). The impact of the treatments was tested on growth performance, nutrient digestibility, blood metabolites, intestinal microflora, and morphology of broiler chicken.

Key results: The inclusion of exogenous enzyme blend in the nutrient-deficient diet S/F 3,060/3,150 + 21.50/19.50 increased (p<0.05) broilers body weight, feed conversion ratio, nutrient digestibility of crude protein, gross energy, phosphorus, and blood phosphorus, with tendency (p<0.10) of higher dry matter. The treatment also showed lower (p<0.05) total anaerobic bacteria, coliform, and higher (p<0.05) villus height (VH) in the jejunum, with tendencies (p<0.10) of higher lactobacillus in the ileum and caecum, and higher tendency (p<0.10) of VH in duodenum and ileum.

Conclusion: We concluded that the improved performance could be attributed to the potency of S/F 3,060/3,150 + 21.50/19.50 supplemented with 0.05% of the multienzyme to reduce the level of potential pathogenic bacteria with an increased level of positive bacteria, which in turn creates an enabling intestinal villi structure in broiler chicken.

Objective: This work was to investigate the effect of using Azolla (Azolla microphylla) leaf meal and phytonutrient powder on rumen fermentation efficiency and nutrient degradability using in vitro technique.

Methods: All respective treatments were imposed in a 2 × 4 × 2 Factorial arrangements according to a completely randomized design (CRD). The first factor was two ratios of roughage to concentrate (R:C at 60:40, and 40:60), the second factor was Azolla (Azolla microphylla) powder (AMP) supplementation levels (0%, 3%, 6%, and 9% of the total substrate) and the third factor was Turmeric (Curcuma longa) powder (TUP) supplementation levels (0% and 2% of the total substrate).

Results: Cumulative gas production at 96 h, was affected by R:C and numerically increased by AMP and TUP supplementation (p<0.05). Gas production kinetics increased with the increasing ratio of concentrate and AMP supplementation whereas TUP supplement reduced gas production. In vitro DM degradability was remarkably increased (p<0.05) by the R:C ratio, AMP and TUP supplementation. However, increasing R:C ratio, AMP and TUP supplementation resulted in the concentration of propionate (C3) significantly increasing (p<0.05). Acetate (C2), C2:C3 ratio, and protozoal population were improved (p<0.05), while the methane production decreased.

Conclusion: Under this study, the results were obtained under the supplementation level of 9% AMP and 2% TUP of total substrate, hence, the combined use is potentially beneficial. These results revealed a potential use of AMP and TUP as a supplement to improve rumen fermentation for ruminant feeding. Nevertheless, in vivo feeding trials should be further investigated using AMP and TUP as a source of protein and phytonutrient.

Objective: This study evaluated the effects of increased levels of dietary total digestible nutrient (TDN) and crude protein (CP) using protected fat (PF), soybean meal (SB), and heat-treated soybean meal (HSB) on performance, physiological parameters, and behavioral measurements of early-fattening Hanwoo steers under heat stress conditions.

Methods: Thirty-six steers (480.9 ± 58.6 kg, 15.9 ± 1.4 months) were assigned to 4 treatments: Control (TDN 75%, CP 15%, rumen degradable protein [RDP]:rumen undegradable protein [RUP]=62:48), PF (TDN 82.5%, CP 15%, RDP:RUP=62:48), PF+SB (TDN 82.5%, CP 16.5%, RDP:RUP=62:48), and PF+SB+HSB (TDN 82.5%, CP 16.5%, RDP:RUP=48:52) for a total of 16 weeks with division of 4 weeks. The average temperature-humidity index (THI) was 82.9 (1st; Moderate), 76.9 (2nd; Mild), 70.9 (3rd; Comfort), and 65.8 (4th period; Comfort).

Results: Dry matter intake during whole period did not differ among treatments but decreased by 34% and 19%, respectively during 1st and 2nd compared to 4th. Average daily gain (ADG) of PF+SB+HSB was higher (p<0.05) than that of Control during the 1st period, and those of both PF+SB and PF+SB+HSB were higher (p<0.05) than Control during the 2nd. The ADG during whole period was in the order of PF+SB+HSB (1.23), PF+SB (1.18), PF (1.11), Control (0.98 kg/d) (p<0.05). As THI increased, rectal temperature and all blood parameters increased, while blood glucose levels decreased (p<0.05). Behavioral changes during 1st period compared to 3rd included decreases in Lying (24%), Walking (48%), and Eating (40%), and increases in Total standing (50%) and Drinking (43%) (p<0.05). Rumination during standing was 38% higher, and Rumination during lying was 32% lower (p<0.05).

Conclusion: This study demonstrates 10% of increased levels of dietary TDN using PF and CP considering RUP can prevent performance reduction in early-fattening of heat-stressed Hanwoo steers and have positive effects on performance recovery from post-heat stress.

Objective: The current study aimed to investigate the effect of dietary supplementation of xylanase alone or combination of xylanase and β-glucanase in high non-starch polysaccharides (NSP) diets with low energy on growth performance, meat quality, intestinal measurements, stress responses, and energy and nutrient utilization in broiler chickens.

Methods: A total of four hundred 8-d-old Ross 308 broiler chickens were randomly allotted to 1 of 4 treatment groups with 10 replicates. A positive control (PC) diet was formulated with adequate energy and nutrients, whereas a negative control (NC) diet had 100 kcal/kg less AMEn than the PC diet with increasing inclusion of high NSP ingredients. Two additional diets were produced by supplementing 0.1% xylanase alone or 0.1% xylanase and β-glucanase mixture in the NC diet. Experiments lasted for 27 d.

Results: Birds fed PC diets had less (p<0.05) FCR than those fed NC diets. Birds fed NC diets supplemented with xylanase alone or combination of xylanase and β-glucanase had less (p<0.05) FCR than those fed NC diets. Dietary supplementation of xylanase alone in NC diets exhibited the highest (p<0.05) breast meat pH among dietary treatments. Birds fed PC diets or NC diets supplemented with xylanase and β-glucanase combination exhibited greater (p<0.05) VH:CD ratio than those fed NC diets. Dietary supplementation of xylanase alone and combination of xylanase and β-glucanase in NC diets decreased (p<0.05) ileal digesta viscosity and increased (p<0.05) xylo-oligosaccharide concentrations in the gastrointestinal tract (GIT) compared with NC diets without affecting energy and nutrient utilization in NC diets.

Conclusion: Dietary supplementation of xylanase in high NSP diets with low energy concentrations improves growth performance by decreasing digesta viscosity and increasing concentrations of xylo-oligosaccharides in the GIT of broiler chickens. However, little additional benefits of β-glucanase supplementation in combination with xylanase are identified for broiler chickens.

Objective: Successful gene editing technology is crucial in molecular biology and related fields. An essential part of an efficient knock-in system is increasing homologous recombination (HR) efficiency in the double-strand break (DSB) repair pathways. Interestingly, HR is closely related to the DNA mismatch repair (MMR) pathway, whereby MMR-related gene Msh2 recognizes a mismatch of nucleotides in recombinant intermediates or gene conversion formed during HR. This study aimed to investigate how the knockdown of Msh2 affects HR-mediated knock-in efficiency at the mouse β-casein locus. Therefore, we investigated the effect of inhibiting Msh2 expression on the expression of the HR-related gene Rad51 and the key enzyme DNA ligase IV involved in non-homologous end joining (NHEJ).

Methods: The knock-in vector targeting the mouse β-casein gene locus, programmed guide RNA, and Msh2 siRNA expression vector were co-transfected in HC11 cells, or only the Msh2 siRNA expression vector was transfected. Knock-in efficiency was confirmed by polymerase chain reaction (PCR). The mRNA and protein expression of Msh2, HR-related gene Rad51, and NHEJ-related gene DNA ligase IV were evaluated by quantitative reverse transcription PCR (RT-qPCR) and Western blot analysis.

Results: The knock-in vector efficiency at the mouse β-casein gene locus significantly decreased upon Msh2 knockdown in HC11 mouse mammary epithelial cells (HC11 cell). Additionally, the knockdown of the DNA MMR-related gene Msh2 protein significantly downregulated the nuclear protein expression of the HR-related Rad51 and NHEJ-related DNA ligase IV genes.

Conclusion: The decreased Msh2 protein expression in the nucleus downregulated the Rad51 and ligase IV protein expressions. Consequently, reduced Rad51 expression results in decreased knock-in efficiency.

Objective: The aim of this study was to determine the effect of rumen-protected rubber seed oil supplementation on feed digestibility, milk yield, and milk composition in tropical dairy cows.

Methods: Twelve crossbred Holstien-Friesian dairy cows (75% Holstein-Friesian, 25% Thai native breed) with a mean body weight (BW) of 460 ± 30 kg and 20 ± 5 days in milk were randomly assigned to 1 of 3 treatments according to a completely randomized design. The treatments were as follows: a basal diet without rumen-protected fat (RPF) (control) or supplementation of rumen-protected palm oil (RPPO) at 300 g/h/d and rumen-protected rubber seed oil (RPRSO) at 300 g/h/d. Each cow was fed a total mixed ration ad libitum.

Results: The nutrient intake was similar among treatments (p>0.05). Adding RPF did not affect nutrient digestibility, while organic matter digestibility increased in dairy cows receiving RPRSO (p<0.01). Blood urea nitrogen, total protein, or glucose did not alter among treatments (p>0.05), while triglycerides and cholesterol were increased when cows were fed RPPO (p<0.01). Adding RPF increases milk yield in cows (p<0.01). The supplementation of RPRSO increased milk fat (p=0.04). Milk fat yield was higher in RPPO and highest in RPRSO (p<0.01). The addition of RPF increased the oleic acid (OA, C18:1 cis-9) in milk (p=0.01). In addition, cows fed RPRSO increased linoleic acid (LA; C18:26 cis-9,12 + trans-9,12) and -linolenic acid (ALA; C18-33 cis-9,12,15) in milk (p<0.01). The addition of RPF increased milk unsaturated fatty acids (UFA) and monounsaturated fatty acids (MUFA) (P≤0.04). The PUFA in milk increased with RPRSO supplementation (p<0.01).

Conclusion: Supplementation of RPRSO during early lactation can increase feed digestibility and the concentration of milk fat with PUFA (LA and ALA) in tropical dairy cows.

Objective: Our study aimed to investigate the gender and age-related variations in rumen fermentation, serum metabolites, and microbiota in Qinchuan cattle.

Methods: A total of 38 Qinchuan beef cattle were selected and maintained on a uniform diet for three months. Rumen fluid and blood samples were collected to determine rumen fermentation, serum metabolites, and microbial 16S rRNA sequencing.

Results: The results revealed that the concentration of rumen butyrate in female Qinchuan cattle was significantly higher than in males (P<0.05). Isobutyrate, butyrate, and isovalerate exhibited significant age-related differences. Females exhibited lower serum GLU and higher TG, NEFA levels compared to males (P<0.05). Serum ALB and UREA levels increased with age (P<0.05). Furthermore, the alpha diversity of rumen bacteria improved with age (P<0.05), with no gender differences observed. Males had higher relative abundances of Bacteroidota, Verrucomicrobiota, and Cyanobacteria, while females had higher Firmicutes and Desulfobacterota (P<0.05). The cellulose-degrading genus Ruminococcus and propionate-producing genus Succiniclasticum were more abundant in females, whereas the anti-inflammatory genus Lachnospiraceae_NK4A136_group and the hemicellulose-degrading genus Prevotella were more abundant in males (P<0.05). Age-related differences in bacteria were found in Pseudobutyrivibrio and several members of the Lachnospiraceae. Functional prediction indicated that "Amino acid metabolism" and "Lipid metabolism" were mainly enriched in females, whereas "Carbohydrate metabolism" and "Glycan biosynthesis and metabolism" were enriched in males (P<0.05). RDA analysis highlighted butyrate as a key factor influencing the rumen bacterial community. NK4A214_group and Ruminococcus were positively correlated with butyrate, while Prevotella and Pseudobutyrivibrio were negatively correlated with butyrate (P<0.05).

Conclusion: We observed a significant improvement in the diversity and stability of rumen microbiota as age increased. Ruminococcus, NK4A214_group, and Prevotella were likely contributors to variations in energy utilization and fat deposition between male and female Qinchuan cattle.

Objective: This study aimed to investigate the effects of rations incorporating rumen degradable protein (RDP), non-fiber carbohydrate (NFC), and sulfur on nutrient utilization, milk production, milk quality, and the economic aspects of dairy goats.

Methods: In the first study, five treatments were tested in a block-randomized design to examine in vitro fermentability and digestibility. Treatments included P0 (control diet), P1 (P0 + 7.5% cassava-NFC), P2 (P0 + 7.5% cassava-NFC and 5% soybean), P3 (P0 + 7.5% cassava-NFC and 5% autoclaved soybean), and P4 (P0 + 7.5% cassava-NFC, 5% autoclaved soybean, and 0.1% sulfur). In the second study, sixteen lactating Saanen-Ettawa crossbreed dairy goats (initial milk production = 0.97 ± 0.25 L/head/day, 30 DIM; body weight = 44.44 ± 7.20 kg) were assigned into four groups and fed treatment diets: R0 (basal diet), R1 (R0 + 12% autoclaved soybean), R2 (R0 + 12% autoclaved soybean and 9% cassava-NFC), and R3 (R0 + 12% autoclaved soybean, 9% cassava-NFC, and 0.11% sulfur). The diets were offered for 7 weeks with a two-week adaptation period. Parameters observed include milk production and quality, milk fatty acids, blood hematology and metabolites, and economic aspects. The study used a block randomized design with initial weight as a block.

Results: The treatment diets in the first study had no effect on in vitro fermentability and digestibility. Treatments R2 and R3 resulted in higher milk production than R0 and R1. Milk quality remained consistent across treatments, while solid non-fat, lactose, and protein was higher in R2 and R3. Blood hematology was unaffected by the treatments. Nutrient efficiency and income over feed cost were enhanced by R2 and R3 treatments.

Conclusion: Protected RDP using autoclaved soybean and cassava-NFC maintained in vitro digestibility, even though it did not improve in vitro fermentability. Precision dairy ration based on RDP, NFC, and sulfur positively impacts milk production, nutrient efficiency, and animal health in dairy goats.

Objective: This study assessed the impact of incorporating imputed SNP information from non-genotyped animals on genomic-polygenic evaluations in a Thai multibreed dairy population under various levels of imputation accuracy.

Methods: Data encompassed pedigree and phenotypic records for 305-day milk yield (MY), 305-day fat (Fat), and age at first calving (AFC) from 12,859 first-lactation cows, and genotypic records of various densities from 4,364 animals. A set of 64 animals genotyped with GeneSeek Genomic Profiler 80K and with four or more genotyped progenies was defined as target animals to simulate imputation scenarios for non-genotyped individuals. Actual and imputed genotypes were utilized to construct three SNP sets. All SNP Sets contained actual and imputed SNP markers from genotyped animals. SNP Set 1 contained no SNPs from target animals, whereas SNP Set 2 incorporated imputed SNPs from target animals, and SNP Set 3 added actual SNPs from target animals. Genomic-polygenic evaluations were conducted using a 3-trait single-step model that included contemporary group, calving age, and heterozygosity as fixed effects and animal additive genetic and residual as random effects.

Results: The imputation accuracy was similar across non-genotyped animals irrespective of the number of genotyped progenies (average: 40.55%; range: 34.68% to 53.82%). Estimates of additive genetic and environmental variances and covariances for MY and AFC varied across SNP sets. SNP Sets 1 and 2 had slightly higher additive genetic and lower environmental variances and covariances than SNP Set 3. Heritabilities and additive genetic, environmental, and phenotypic correlations between MY, Fat, and AFC were similar across all SNP Sets. Spearman rank correlations between genomic-polygenic EBVs from SNP Sets 2 and 3 were high for all traits (0.9990±0.0003).

Conclusion: Utilization of phenotypic and pedigree data from imputed non-genotyped animals enhanced the efficiency and cost-effectiveness of the genetic improvement program in the Thai multibreed dairy cattle population.