Animal Bioscience最新文献

Objective: Improving meat quality is important for commercial production and breeding. The molecular mechanism of intramuscular fat (IMF) deposition and meat characteristics remain further study.

Methods: This study aimed to study the mechanism of IMF deposition and meat characteristics including redox potential, nutrients compositions and volatile compounds in longissimus dorsi (LD) by comparing with different pig breeds including Shanghai white (SW), Duroc x (Landrace Yorkshire) (DLY) and Laiwu (LW) pigs.

Results: Results showed that the contents of IMF, triglyceride (TG), total cholesterol (TC), and redox potential parameters were lower, while the content of MDA and activity of lactate dehydrogenase (LDH) were higher in LD of SW pigs compared with LW pigs (p<0.05). No differences were observed about these parameters between SW and DLY pigs. Also, the contents of medium-long chain fatty acids and γ-aminobutyric acid (GABA) were higher, while Asp was lower in LD of SW pigs compared with LW pigs (p<0.05). Volatile compounds results showed that 6 ketones, 4 alkenes, 11 alkanes, 2 aldehydes, 1 alcohol were increased and cholesterol was decreased in SW pigs compared with LW pigs. Transcriptome results showed that differential expressed genes involved in lipid synthesis, metabolism and transport in LD between SW and LW pigs, which were further verified by qPCR. Spearman correlation showed that HSL and Nedd4 were positively related to contents of TG and IMF, while negatively related to volatile compounds and fatty acids (p<0.05). Plin3 and Mgll were negatively related to contents of TG, IMF and cholesterol, while positively related to MDA, LDH, and volatile compounds (p<0.05). PPARA was negatively related to contents of TC and IMF, and activity of SOD, while positively related to volatile compounds (p<0.05).

Conclusion: Our study provided new insights into potential mechanisms of IMF deposition, nutrients composition and volatile compounds of muscular tissues of different pig breeds.

Objective: The aim of this study was to obtain goat CRTC2 gene sequence and elucidate its biological properties, and further study the impact of overexpression and interference of CRTC2 on the cell differentiation of goat subcutaneous precursor adipocytes.

Methods: The sequence of goat CRTC2 was cloned by reverse transcription polymerase chain reaction (RT-PCR) and its molecular characterization was analyzed. The expression of CRTC2 gene in goat tissues and subcutaneous precursor adipocytes differentiated from 0 to 120 h was examined by quantitative real-time PCR (qRT-PCR). The effects of CRTC2 on the subcutaneous precursor adipocyte differentiation were investigated by using liposome transfection, Bodipy, Oil Red O staining and qPCR.

Results: The results showed that the cloned goat CRTC2 gene was 2363 bp long (coding sequence [CDS] 2082 bp), encoding 693 amino acids. The relative expression levels of CRTC2 gene were highest in liver and then in kidney (P < 0.05). During differentiation, the highest expression of CRTC2 in subcutaneous precursor adipocytes was observed at 120 of differentiating (P < 0.01). In addition, we found that overexpression of CRTC2 significantly increased the expression of lipid metabolism-related genes (C/EBPα, C/EBPβ, PPARγ, DGAT1, DGAT2, ACC, FASN, SREBP1，AP2，LPL，ATGL) and promoted lipid accumulation. We then chemically synthesized goat CRTC2 small interfering RNA and transfected it into goat subcutaneous precursor adipocytes. The results revealed that SiRNA-mediated interference with CRTC2 significantly inhibited its differentiation and suppressed lipid droplet aggregation.

Conclusion: So, this study indicates that CRTC2 is a positive regulator that promoting cell differentiation of subcutaneous adipocyte in goats, which lays the foundation for an in-depth study of the role of CRTC2 in lipid deposition in goats.

Objective: This study examined the effects of a nutrient matrix with or without phytase on the performance of broiler chicken.

Methods: A total of 2000 day-old Ross 308 broiler chickens were assigned to 5 dietary treatments, with 10 broilers per replicate and 40 replicates per treatment. The experimental diets included 1. CON: A corn and soybean meal (SBM)-basal diet without phytase. 2, NC1: A corn-SBM-based diet with reduced nutrients, specifically 0.13% less phosphorus, 40 Kcal/kg less metabolizable energy (ME), and 0.30% less crude protein (CP), without phytase. 3, NC1+PHYT: NC1+500 FTU/kg phytase. 4, NC2: Another corn-SBM-based diet with greater nutrient reductions, including 0.16% less phosphorus, 55 Kcal/kg less metabolizable energy (ME), and 0.45% less crude protein (CP), without phytase. 5, NC2+PHYT: NC2+1000 FTU/kg phytase.

Key results: In the pre-starter and overall phase, feed conversion ratio (FCR) was higher in NC2 and NC2+PHYT. In the starter phase, body weight gain (BWG) was lower in NC2 and NC2+PHYT. In the grower phases, BWG was lower in NC2, while FCR was higher. At d28, the digestibility of ash was higher in NC1+PHYT, while the digestibility of Ca and phosphorus were higher in NC1+PHYT and NC2+PHYT. At day 42, the digestibility of ash, Ca, and phosphorus were higher in NC1+PHYT and NC2+PHYT. The level of tibia ash was lower in NC2. The level of myo-inositol was lower in NC2 at d28, while the level of myo-inositol at d42 was lower in NC1 and NC2.

Conclusion: We concluded NC1+PHYT showed a higher growth performance comparable to CON, as against the lower performance observed in NC2, NC2+PHYT, and NC1.

Objective: In this study, we investigated the effects of heat stress (HS) on rumen fermentation, blood parameters, and ruminal microbial communities in mid-lactating Holstein dairy cows in Korea.

Methods: Our study involved 12 mid-lactation Holstein dairy cows aged 55.54 months with 2.5 ± 0.65 parities and 100 to 200 days in milking (DIM), fed a total mixed ratio (TMR) diet. Samples were collected during HS (temperature-humidity index (THI) = 81.69) and recovery (RC) period (THI 69.84). The samples were analyzed for rumen fermentation, blood parameters, heat shock proteins, and microbial communities in dairy cows.

Results: The milk yield, milk fat, milk protein, and milk urea nitrogen (MUN) levels differed significantly between two -time points (p < 0.05). Rumen pH and volatile fatty acid (VFA) concentrations, the pH was not significantly different (p=0.619) between HS and RC periods; however, the ammonia nitrogen (NH3-N) levels increased during HS period ), however, there was no significant difference (p>0.05). Blood total protein significantly increased during HS period compared with that during RC period (p < 0.05), while no significant differences were observed in other parameters between the two periods. HSP27, HSP70, and HSP90 increased in dairy cows under HS conditions compared with those during the RC period. Taxonomic classification revealed that Firmicutes and Bacteroidetes dominated the bacterial community. PERMANOVA and PERMDISP showed significant differences in rumen bacterial diversity between HS and RC periods, based on Unifrac metrics (p=0.044 and p=0.015, respectively), indicating taxonomic variations. Microbial networks with correlations of > 0.8 (p < 0.05) showed a complex structure with equal positive and negative connections, indicating Anaerohabdus furcosa and Ruminiclostridium cellobioparum as key species during the HS and RC periods respectively.

Conclusion: Heat stress significantly impacts Holstein dairy cows' physiological and metabolic processes, altering rumen fermentation, blood biochemistry, and gut microbiota during mid-lactation.

Objective: This study aimed to assess the impact of host-specific and locally isolated multi-strain probiotics on piglet performance, mortality, inflammatory responses, and gut microbiome.

Methods: A total of 52 piglet litters-34 from Landrace sows and 18 from Large White sows-were allocated to two groups: a control group and a multi-strain probiotic group. The probiotic group comprised seven strains of lactic acid bacteria (MLAB): Lactobacillus brevis, Lactobacillus reuteri, Lactobacillus paraplantarum, Lactococcus lactis, Lactobacillus pentosus, Weissella cibaria, and Pediococcus pentosaceus. Each strain was included in equal concentrations, resulting in a final liquid mixture containing 109 CFU/mL. The MLAB group received the probiotics orally starting from 7 days of age until weaning at four weeks. Following weaning, supplementation continued via feed spraying for an additional four weeks.

Results: MLAB supplementation did not significantly affect piglet performance but showed a trend towards reducing the mortality rate (p = 0.06). It influenced the inflammatory response by upregulating the expression of anti-inflammatory cytokines interleukin (IL)-4 and IL-10 (p<0.05). Microbial community analysis indicated that MLAB supplementation increased both microbial diversity (Simpson index: p = 0.06) and species richness (Chao1 index: p = 0.02). Piglets receiving MLAB had a significantly higher abundance of the phylum Firmicutes (p<0.01) compared to the control group, while the abundance of the phylum Bacteroidota was markedly reduced (p<0.01). In addition, the relative abundance of the bacterial genera Prevotellaceae_NK3B31 (p<0.01) and Chlamydia (p = 0.03) was lower in the MLAB group.

Conclusion: Overall, these results suggest that while MLAB supplementation does not directly improve piglet growth performance, it has the potential to improve immune function and promote a healthier gut microbiota in weaning piglets, which could ultimately reduce mortality rates.

Objective: Pre-slaughter transportation adversely impacts the welfare, meat yield, and quality of broilers, yet the effects of different crate types on broiler chickens during winter remain underexplored. The goal of this study was to investigate the effect of plastic and iron crates in transit on meat quality, carcass, and physiological traits of broiler chickens during winter.

Methods: A total of 175, 35-day-old Ross 308 male broilers with an average body weight of about 1,708 ± 33.3 g (mean ± standard error of the mean) were picked after 4 hours of feed withdrawal before transport. The control group comprises birds in the farm (n = 15) without transportation at 173 cm2/kg density. The birds were transported into fixed iron (25 birds per crate) and plastic crates (15 birds per crate) with four replicates per crate type at the same 173 cm2/kg densities. The transportation distance was 20 km for 40 min at an average speed of 30-50 km/h early morning at 8:00 am under - 1 ℃ and 47% relative humidity.

Results: There was no difference (p>0.05) in carcass traits among the treatments. Concerning meat quality, broilers transported in both crate types exhibited lower (p<0.01) a* values compared to the control group. Additionally, the iron crate group demonstrated higher (p<0.05) b* values for the breast meat compared to the other groups. In terms of blood metabolites, the iron crate group had higher (p<0.05) cortisol, glucose, and lactate levels compared to the control group that did not transport.

Conclusion: Broilers transported in the iron crates increase stress levels in terms of higher cortisol, glucose, and lactate contents in the blood plasma compared to untransported broilers during the winter. Therefore, employing plastic crates, which induce significantly reduced cortisol and numerically lower glucose levels compared to iron crates, appears more favorable for animal welfare by mitigating stress.

Objective: This study aimed to investigate the impact of different level of soybean meal (SBM) replaced by soy protein concentrate on intestinal health and growth performance of nursery pigs under F18+ Escherichia. coli (E. coli).

Methods: Forty-eight newly weaned pigs (6.6 ± 0.3 kg) were randomly allotted to 4 treatments arranged by 2 × 2 factors using randomized complete block design with initial body weight and sex as blocks. Two factors were F18+ E. coli challenge (0 or 2.1 × 1010 CFU) and the level of SBM (24% or 12% in phase 1 and 26% or 14% in phase 2). Pigs were fed for 25 d in 2 phases (phase 1 for 11 d and phase 2 for 14 d). At the end of study, all pigs were euthanized to collect jejunal mucosa and tissues to measure parameters related to intestinal health. Data were analyzed using a MIXED procedure in SAS.

Results: The F18+ E. coli challenge decreased (p<0.05) overall average daily gain (ADG) and average daily feed intake (ADFI) and decreased (p<0.05) gain to feed ratio on d 7 to 11. The High SBM tended to have a greater overall ADG (p=0.054) and ADFI (p=0.078) compared with low SBM under F18+ E. coli challenge, but not in unchallenged conditions. The F18+ E. coli challenge increased (p<0.05) fecal score on d 7 to 18. The tumor necrosis factor-alpha and interleukin-1β in jejunal mucosa were decreased (p<0.05) in High SBM treatments. The High SBM tended to increase (p=0.085) occludin expression in jejunum. High SBM increased crypt depth in jejunum under F18+ E. coli challenge, but not in unchallenged conditions (p<0.05).

Conclusion: High SBM in nursery diets could alleviate the detrimental effects of F18+ E. coli challenge on growth performance of pigs under compared to low SBM inclusion, which might be attributed to decreased intestinal inflammation and improved intestinal integrity.

Objective: This research aims to explore the effects of incorporating saccharomyces cerevisiae fermentation products (SCFP) on growth performance, nutrient digestibility, antioxidant capacity, fecal SCFAs, and microbial composition of pre-weaning calves.

Methods: Twenty Holstein calves, 10 days old and weighing an average of 48.63±0.91 kg, were randomly assigned to either the control group (CON) or the SCFP group, with 10 calves in each group. The CON group received only a basal diet, while the SCFP group received the starter diet supplemented with 5 g/head/d of SCFP products (NutriTek, Diamond V Cedar Rapids, IA 52404, United States). The pre-trial period lasted for 5 days, followed by a main experimental period of 45 days.

Results: The SCFP group had significantly higher final weight, ADG, and FE compared to the control group (p < 0.05). Moreover, the SCFP group exhibited increased apparent digestibility of DM, CP, EE, ADF, Ca, and P (p < 0.05). Additionally, supplementation with SCFP led to elevated content of GH, IGF-1, and GLP-1 in serum. The inclusion of SCFP also raised serum CAT content and reduced serum MDA content in pre-weaning calves. Furthermore, SCFP supplementation influenced the composition of intestinal microflora by decreasing Actinobacteriota abundance and increasing the abundance of Ruminococcus, Lachnospiraceae_AC2044_group, Parabacteroides, and Butyricimonas.

Conclusion: The addition of SCFP has a positive impact on the growth performance, nutrient digestibility, antioxidant capacity, and intestinal microflora composition of pre-weaning calves.

Objective: This study evaluated the effects of dietary sodium sulfate (Na2SO4) supplementation on eggshell quality, uterine ion transportation, and glycosaminoglycan (GAG) synthesis.

Methods: A total of 432 48-wk-old Hy-line Brown laying hens were randomly divided into 6 dietary treatments with 8 replicates of 9 birds each. The experimental laying hens were fed the corn-soybean meal diets (containing 0.15% NaCl) supplemented with 0.22%, 0.37%, 0.52%, 0.68%, 0.83%, or 0.99% Na2SO4 for 12 weeks.

Results: Results showed that the eggshell breaking strength and eggshell ratio significantly increased in the 0.68% Na2SO4 group at the end of wk 56 and wk 60 (P < 0.05). In addition, eggshell thickness and weight significantly increased in the 0.68% Na2SO4 group at the end of wk 60 (P < 0.05). Eggshell calcium (Ca) content in the 0.68% Na2SO4 group was higher than that of 0.22% and 0.99% groups (P < 0.001). The concentrations of K+ and Ca2+ in the uterine fluid were significantly greater in the 0.68% group than in the other groups (P < 0.05). Dietary Na2SO4 increased the gene expression of SLC8A1, SCNN1A, ATP1B1, and KCNMA1 quadratically in the uterus (P < 0.05), and higher values were observed in 0.68% group. Additionally, the GAG contents of the eggshell, and ATP-S, SULT, CS, and DS contents of the isthmus increased linearly with the increment of dietary Na2SO4 (P < 0.05). There was a remarkable reduction in mammillary knob width, mammillary thickness, and the percentage of the mammillary layer (P < 0.05), and an increment in mammillary knob density, effective thickness, and total thickness in the 0.68% group compared with the 0.22% and 0.99% groups (P < 0.05).

Conclusion: Overall, there was no dose-related difference with the increment of dietary Na2SO4 levels. The addition of 0.68% Na2SO4 in the corn-soybean basal diet (0.15% Cl) regulated uterine ion transport, increased GAG contents of eggshell, and improved eggshell ultrastructure and quality.

Objective: Antemortem stress accelerated muscle energy consumption in postmortem muscle. The objective of our study was to investigate the regulation of guanidinoacetic acid (GAA) administration on the postmortem glycolysis and protein acetylation in postmortem muscle of antemortem stress.

Methods: Forty C57BL/6 male mice were chosen and randomly assigned to four treatment groups (A, B, C and D), each treatment consisted of 10 replicates. Mice in group B, C and D were treated with 0.05% GAA oral administration for 6 days. On the 7th day of the experiment, the mice in group A and B were injected with saline, and mice in group C and D were injected with 5-aminoimidazole-4-carboxamide1-β-D-ribofuranoside (AICAR,50 μg/g body weight) and a combined injection with AICAR (50 μg/g body weight) and histone acetylase inhibitor Ⅱ (HAT Ⅱ,185 μg/g body weight), respectively.

Results: The results showed that the values of pH45min and pH24h of postmortem muscle in GAA administration were higher than those in the control group. However, the opposite result was observed in AICAR group. Moreover, the activities of acetone kinase, hexokinase and fruc-tose-2,6-diphosphatase, combined with the protein abundance of phosphorylated liver kinase, phosphorylated AMPKα2 and total acetylated protein were all decreased by GAA administration and HAT Ⅱ treatment.

Conclusion: Taken together, AMPK signaling and protein acetylation could mediate the regulation of GAA administration on postmortem glycolysis of antemortem stress-muscle.