Animal Bioscience最新文献

Objective: Palmitic acid (PA), the most abundant saturated free fatty acids, induces apoptosis in bovine mammary epithelial cells (MECs). It is suggested that oxidative stress and endoplasmic reticulum (ER) stress are key mechanisms underlying PA-induced cell death. This study aimed to investigate the interaction between ER stress and oxidative stress during PA-induced cell death in mammary alveolar cell-T (MAC-T) cells. Additionally, we examined whether L-citrulline can protect against PA-induced damage of MAC-T cells.

Methods: MAC-T cells were treated with 4-phenyl butyric acid (4-PBA) or N-acetyl-Lcysteine (NAC) to inhibit PA-induced ER stress and oxidative stress, respectively. MAC-T cells were pretreated with or without L-citrulline for 48 h followed by PA treatment. Cell viability was measured with MTT assays. Intracellular reactive oxygen species (ROS) levels in MAC-T cells were assessed using 5-(and-6)-chloromethyl-2',7'-dichlorodihydrofluores cein diacetate acetyl ester dye. Real-time quantitative polymerase chain reaction was used to explore the regulation of genes associated with oxidative stress, and ER stress genes. Western blotting analysis was also carried out.

Results: 4-PBA significantly reduced PA-induced mRNA expressions of activating transcription factor 4 (ATF4), C/EBP homologous protein (CHOP), nuclear factor (erythroid-derived 2)-like 2 (NRF2), and intracellular ROS levels. Furthermore, NAC dramatically reduced PA-induced ROS levels and the mRNA expressions of NRF2, ATF4, and CHOP. L-citrulline pretreatment effectively rescued cell viability decreased by PA. Moreover, L-citrulline pretreatment significantly downregulated the PA-induced upregulation of GRP78, ATF4, and CHOP mRNA expression, and protein expression of p-PERK and cleaved caspase-3. PA increased intracellular ROS levels and NRF2 mRNA expression, whereas L-citrulline pretreatment remarkably reduced these levels.

Conclusion: Both ER and oxidative stresses interact during PA-induced cell death in MAC-T cells, and L-citrulline could attenuate this cell death by inhibiting ER and oxidative stresses. Therefore, L-citrulline may be a promising supplement for protecting against PA-induced cell death in bovine MECs during the lactation period of dairy cows.

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 (16 L:8 D) or short photoperiod (SP) group (10 L:14 D) 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 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 downregulated in LP group compared to SP group. Extended photoperiod also increased lipid content in longissimus dorsi muscle 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/d) 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.

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 CP, 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: The objective of this work was to determine the energetic values of 14 full-fat deactivated soybeans samples, the effect of partial removal of the hull, and to develop equations for predicting digestible (DE), metabolizable (ME), and ME corrected for nitrogen balance (MEn) for pigs.

Methods: Ten metabolism experiments were conducted over a two-year period to evaluate 14 batches of full-fat deactivated soybeans, following the method of the total collection of feces and urine. One hundred and ninety-two pigs with an average initial body weight of 51.4±5.4 kg were assigned to dietary treatments.

Results: Partial dehulling of soybeans did not affect DE, ME, and MEn values. The variables that best explained the variations (p<0.05) in DE were ureatic activity (UA) and crude fiber. The variables that showed the greatest association (p<0.05) with ME and MEn were UA, protein solubility, and processing pressure. The observed effect of UA on energy values was quadratic (p<0.05). Phosphorus also showed association (p<0.05) with DE and ME and the energy applied per kg of sample showed association (p<0.05) with ME and MEn.

Conclusion: The overall mean values of DE, ME, and MEn were 4,558, 4,457, and 4,344 kcal/kg, respectively. The partial removal of the hull prior to soy deactivation did not affect the digestibility or the energy values. This study shows that the processing conditions are the main factors affecting the energetic value of full-fat deactivated soybeans for pigs, which can be accurately predicted using a combination of chemical composition, quality indicators, and processing parameters.

Objective: Subclinical mastitis decreases milk production and quality, despite the normal appearance of the mammary glands and milk. Herein, we aimed to investigate changes in factors monitored via automatic milking systems (AMS) prior to subclinical mastitis onset and identify differences in hematological and biochemical parameters and milk composition at subclinical mastitis onset.

Methods: Thirty-two Holstein cows were divided into two groups according to somatic cell counts (SCC) from AMS and milk composition analysis and the California mastitis test (CMT): healthy cows (controls [CON], n = 16, SCC <500×103 cells/mL and negative for CMT) and cows with subclinical mastitis (SCM, n=16, SCC ≥500×103 cells/mL and positive for CMT). Eventually, 121 milk samples from the CON ([mCON], n = 60) and SCM ([mSCM], n = 61) groups were obtained; SCM samples were categorized as those from non-inflamed (mNQ) or subclinically-inflamed (mIQ) quarters. We evaluated AMS factors; hematological, biochemical, and milk composition parameters; and bacterial isolation.

Results: In cows with SCM, milk yield decreased, and electrical conductivity (EC) changed before disease onset. Milk EC decreased in mNQ although increased in mIQ (p<0.05). The SCM group had higher globulin levels and lower basophil counts; albumin-to-globulin ratio; and total cholesterol, albumin, and blood urea nitrogen levels than the CON group (p<0.05). The mIQ group had higher SCC but lower levels of lactose and milk solids-notfat than those in the mCON and mNQ groups (p<0.05). The mCON group had higher levels of milk non-protein nitrogen than the mNQ group (p<0.05). Opportunistic mastitis pathogens were isolated in the mIQ group.

Conclusion: Changes in milk yield and EC measured using AMS occurred prior to subclinical mastitis, which may be associated with variation in basophil counts; albumin-toglobulin ratio; and total cholesterol, albumin, blood urea nitrogen, globulin, SCC, milk lactose, and milk solids-not-fat levels at disease onset. These findings provide new insights into early-stage subclinical mastitis.

Objective: The objective of this study was to evaluate the use of condensed tannin from black acacia (Acacia mearnsii) as a substitute additive for zinc oxide and growth-promoting antibiotics on the performance, digestibility, and intestinal health of piglets in the nursery phase.

Methods: A total of 200 PIC piglets that were 22 days old and weighed 6.0±0.9 kg were subjected to four treatments in the nursery phase (22 to 64 days of age): CONTR (control diet); ENR+ZnO (control diet + 10 mg/kg of enramycin + 2,500 mg/kg of zinc oxide during the first 21 days); BUT (control diet + 900 mg/kg of sodium butyrate) and TAN (control diet + 2,000 mg/kg of condensed tannin). The experimental design was a randomized block with 4 treatments and 10 replicates, with a pen of five animals each as the experimental unit. The zootechnical performance, diarrhea index score, dietary digestibility and metagenomics of the deep rectum microbiota were evaluated.

Results: The TAN had greater weight gain in the nursery phase and final weight (p<0.05) than the CONTR (394 vs 360 g/d, and 22.6 vs 21.1 kg, respectively), with these values being intermediate for the ENR+ZnO and BUT (365 and 382 g/d, and 21.3 and 22.1 kg, respectively). There was no difference between treatments for semi-liquid diarrhea (score 2), but CONTR had more cases of severe diarrhea (score 3; p<0.05) than ENR+ZnO, BUT and TAN, with 42, 18, 29, and 21 cases, respectively. The treatments had no impact on rare taxa or the relative abundances of taxonomic groups (uniformity), but the use of TAN promoted an increase in the abundances of Brevibacillus spp. and Enterococcus spp. compared to the other treatments (p<0.05).

Conclusion: The use of condensed tannin from black wattle as a performance-enhancing additive was effective, with effects on performance and intestinal health, demonstrating its potential as a substitute for zinc oxide and enramycin in the diets of piglets in nursery phase.

Green nanotechnology is an emerging field of research in recent decades with rapidly growing interest. This integrates green chemistry with green engineering to avoid using toxic chemicals in the synthesis of organic nanomaterials. Green nanotechnology would create a huge potential for the use of nanoparticles for more sustainable utilization in improving animal health. Nanoparticles can be synthesised by physical, chemical and biological processes. Traditional methods for physical and chemical synthesis of nanoparticles are toxic to humans, animals and environmental health, which limits their usefulness. Green synthesis of nanoparticles via biological processes and their application in animal health could maximize the benefits of nanotechnology in terms of enhancing food animal health and production as well as minimize the undesirable impacts on Planetary Health. Recent advances in nanotechnology have meant different nanomaterials, especially those from metal sources, are now available for use in nanomedicine. Metal nanoparticles are one of the most widely researched in green nanotechnology, and the number of articles on this subject in food animal production is growing. Therefore, research on metal nanoparticles using green technologies have utmost importance. In this review, we report the recent advancement of green synthesized metal nanoparticles in terms of their utilization in monogastric animal health, elucidate the research gap in this field and provide recommendations for future prospects.

The increase in methane emissions, a major greenhouse gas, threatens human well-being and global ecosystems due to its contribution to global warming. Livestock, particularly ruminants, have been a major research topic in recent decades due to their methane production. Therefore, the objective of the current review was to comprehensively discuss the in silico techniques used to mitigate methane production from ruminants. The review covers the principles of in silico docking and molecular dynamics, which can be used to develop methanogenesis inhibitors. It also discusses specific methanogen enzymes as potential targets for inhibitor development. Furthermore, in silico-based methanogenesis inhibitor development studies have been reviewed with the authors' opinions. The further use of in silico-based research techniques, including artificial intelligence-based systems, is encouraged to help reduce methane production from livestock more efficiently and costeffectively.

Objective: This study was conducted to reveal the role of nuclear poly(A) binding protein 1 (PABPN1) in the proliferation of preadipocytes, and to reveal the relationship between PABPN1 and cAMP response element (CRE)-binding protein (CREB) in the regulation of preadipocyte proliferation.

Methods: Vectors overexpressing and siRNAs against PABPN1/CREB were transiently transfected into both porcine preadipocytes and mouse 3T3-L1 cells. Preadipocyte proliferation was measured with cell counting kit-8, 5-ethynyl-2'-deoxyuridine, real-time quantitative polymerase chain reaction, Western blotting, and flow cytometry analyses. Additionally, the transcriptional regulation of CREB on PABPN1 were analyzed with dual-luciferase reporter gene and electrophoretic mobility shift assay.

Results: Overexpression of PABPN1 inhibits, and knockdown of PABPN1 promotes, the proliferation of both porcine preadipocytes and 3T3-L1 cell lines. PABPN1 overexpression increased, while knockdown decreased, the cell population in the G0/G1 phase. These indicates that PABPN1 repressed preadipocyte proliferation by inhibiting cell cycle progress. Additionally, it was revealed that CREB regulated the expression of PABPN1 through binding to the promoter and that CREB inhibited preadipocyte proliferation by repressed cell cycle progress. Furthermore, we showed that PABPN1 functions as a downstream gene of CREB to regulate the proliferation of preadipocytes.

Conclusion: PABPN1 inhibits preadipocyte proliferation by suppressing the cell cycle. We also found that CREB could promote PABPN1 expression by binding to a motif in the promoter. Further analysis confirmed that PABPN1 functions as a downstream gene of CREB to regulate the proliferation of preadipocytes. These results suggest that the CREB/PABPN1 axis plays a role in the regulation of preadipocyte proliferation, which will contribute to further revealing the mechanism of fat accumulation.

Objective: The primary objective of this study was to investigate the role and regulatory mechanisms of platelet-derived growth factor subunit B (PDGFB) in muscle differentiation.

Methods: In this study, a vector for PDGFB was designed and transfected into quail muscle cells to investigate its role and regulatory mechanism during muscle formation. To investigate the inhibitory mechanisms of PDGFB on myogenic differentiation, the mRNA expression levels of various genes and the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK 1/2), both known to regulate muscle development and differentiation were compared.

Results: PDGFB-overexpressed (OE) cells formed morphologically shorter and thinner myotubes and demonstrated a smaller total myotube area than did the control cells. This result was also confirmed at the molecular level by a reduced amount of myosin heavy chain protein in the PDGFB-OE cells. Therefore, PDGFB inhibits the differentiation of muscle cells. Additionally, the expression of myogenin (MYOG) significantly decreased in the PDGFBOE cells on days 2 and 4 compared with that in the control cells. The phosphorylation of ERK 1/2, an upstream protein that inhibits MYOG expression, increased in the PDGFB-OE cells on day 4 compared with that in the control cells. The decreased expression of MYOG in the PDGFB-OE cells increased by inhibition ERK 1/2 phosphorylation.

Conclusion: PDGFB may suppress myogenesis by reducing MYOG expression through ERK 1/2 phosphorylation. These findings can help understand muscle differentiation and potentially improve poultry meat production.