Nutritional impact of mycotoxins in food animal production and strategies for mitigation

Mycotoxins are toxic secondary metabolites produced by filamentous fungi that are commonly detected as natural contaminants in agricultural commodities worldwide.Mycotoxin exposure can lead to mycotoxicosis in both animals and humans when found in animal feeds and food products,and at lower concentrations can affect animal performance by disrupting nutrient digestion,absorption,metabolism,and animal physiology.Thus,mycotoxin contamination of animal feeds represents a significant issue to the livestock industry and is a health threat to food animals.Since prevention of mycotoxin formation is difficult to undertake to avoid contamination,mitigation strategies are needed.This review explores how the mycotoxins aflatoxins,deoxynivalenol,zearalenone,fumonisins and ochratoxin A impose nutritional and metabolic effects on food animals and summarizes mitigation strategies to reduce the risk of mycotoxicity.

Occurrence of Aflatoxin B_(1),deoxynivalenol and zearalenone in feeds in China during 2018-2020

Background:The current study was conducted to investigate the individual and combined occurrence of aflatoxin B_(1)(AFB_(1)),deoxynivalenol(DON)and zearalenone(ZEN)in feeds from various Provinces of China during 2018 to 2020.A total of 3,507 feed samples,including 2,090 feed ingredients and 1,417 complete feed samples,were collected from different areas of China for mycotoxins analysis.Results:The individual contamination of AFB_(1),DON and ZEN were present in more than 81.9%,96.4% and 96.9% of feed samples,respectively,with average concentration ranges of AFB_(1) between 1.2-27.4μg/kg,DON between 458.0-1,925.4μg/kg and ZEN between 48.1-326.8μg/kg.Notably,0.9%,0.5% and 0.1% of feed ingredients,and 1.2-12.8%,0.9-2.9% and 0-8.9% of complete feeds for pigs,poultry and ruminants with AFB_(1),ZEN and DON that exceeded China’s safety standards,respectively.Moreover,more than 81.5%of feed ingredients and 95.7% of complete feeds were co-contaminated with various combinations of these mycotoxins.Conclusion:This study indicates that the feeds in China were universally contaminated with AFB_(1),DON and ZEN during the past 3 years.These findings highlight the significance of monitoring mycotoxin contaminant levels in the domestic animal feed,and the importance of carrying out feed administration and remediation strategies for mycotoxin control.

Current and future prospects for nanotechnology in animal production

Nanoparticles have been used as diagnostic and therapeutic agents in the human medical field for quite some time, though their application in veterinary medicine and animal production is still relatively new. Recently,production demands on the livestock industry have been centered around the use of antibiotics as growth promoters due to growing concern over microbial antibiotic resistance. With many countries reporting increased incidences of antibiotic-resistant bacteria, laws and regulations are being updated to end in-feed antibiotic use in the animal production industry. This sets the need for suitable alternatives to be established for inclusion in feed.Many reports have shown evidence that nanoparticles may be good candidates for animal growth promotion and antimicrobials. The current status and advancements of nanotechnological applications in animal production will be the focus of this review and the emerging roles of nanoparticles for nutrient delivery, biocidal agents, and tools in veterinary medicine and reproduction will be discussed. Additionally, influences on meat, egg, and milk quality will be reviewed.

Shifts in the Holstein dairy cow milk fat globule membrane proteome that occur during the first week of lactation are affected by parity

Background:The milk fat globule membrane(MFGM)proteomes of colostrum and transition milk are rich sources of proteins that are likely important for neonatal calf health.In addition,characterization of these proteomes could also yield valuable information regarding mammary gland physiology of the early postpartum lactating cow.The objectives of this research were to characterize the MFGM proteomes of colostrum and transition milk through sample collections at four timepoints postpartum,including the first milking(M1,colostrum),second milking(M2,transition milk),fourth milking(M4,transition milk),and fourteenth milking(M14,mature milk),and compare these proteomes between multiparous(MP;n=10)and primiparous(PP;n=10)Holstein dairy cows.Isolated MFGM proteins were labeled using Tandem Mass tagging and analyzed using liquid chromatography-tandem mass spectrometry(LC-MS/MS).Protein identification was completed using MASCOT and Sequest in Proteome Discoverer 2.2.The scaled abundance values were analyzed using PROC MIXED in SAS to determine the effects of milking(MIL),parity(PAR),and MIL×PAR.The adaptive false-discovery rate(FDR)-adjusted P values were determined using PROC MULTTEST.Protein characterization and bioinformatic analysis were completed using a combination of PANTHER,Blast,and Uniprot.Results:A total of 104 common proteins were identified in each of the MFGM samples.Statistical analysis revealed that 70.2%of identified proteins were affected by MIL.Of these,78.1%were lower in M14 compared with M1,including immune-related proteins lactotransferrin,lactadherin and hemopexin.Parity affected 44.2%of proteins.Of the proteins affected by PAR,84.8%were higher in MP cows compared with PP cows,including apolipoprotein E and histones 2A,2B,3,and 4 b.Butyrophilin subfamily 1 member 1A and annexin 5 were higher in samples from PP cows.Milking×parity affected 32.7%of identified proteins,including lactotransferrin,gelsolin,vitamin D binding protein,and S100 proteins.Conclusions:This research supports previous findings that the Holstein MFGM proteome changes rapidly during the first week of lactation.In addition,this research identifies the impact of parity on the colostrum and transition milk MFGM proteomes,which may be important for milk-fed calf health or for the identification of protein biomarkers for mammary functionality.

Milk Replacer Acidification for Free-Access Feeding: Effects on the Performance and Health of Veal Calves

Objectives of this study were to investigate the effects of milk replacer (MR) acidification for free- access feeding on pre- and post-weaning performance, morbidity and mortality of calves. Calves were randomly assigned to free-access feeding of acidified (ACID, n = 31) or non-acidified (NON, n = 31) MR, and weaned at 42 days. ACIDMR was prepared to pH 4.0 - 4.5 using formic acid. Intakes were measured daily and weights weekly. Samples of ACID and NON MR were analyzed for coliform and aerobic bacterial growth. After weaning, calves transitioned to a grain-fed veal diet, weighed every 2 weeks. At slaughter (approximately 6 months of age), lungs were evaluated for gross pathological changes and dressed carcass weights were obtained. Generalized linear mixed models were constructed to examine the effects of MR acidification. Differences by treatment group for pre- and post-weaning morbidity and mortality were tested using Pearson’s χ2 and Fisher’s exact tests. ACID calves consumed less MR than NON (10.6 vs. 11.7 L/d, P = 0.02). Acidification tended to promote earlier onset of starter ration consumption (32.0 vs. 39.5 d, hazard ratio = 1.5, P = 0.07), but did not affect average daily starter ration or water intakes across the pre-weaning period. ACID and NON calves did not differ for BW at weaning, pre- or post-weaning ADG or dressed carcass weight. ACID MR had less coliform (P < 0.001) and aerobic bacterial growth (P < 0.001) than NON MR, but odds of disease treatment and mortality did not differ. ACID calves tended to have lower odds of pulmonary lesions during post-mortem inspection than NON calves (OR = 0.3, P = 0.07). These results indicate that under free-access feeding conditions, acidification limited bacterial growth and MR intake, but there were no long-term impacts of acidification on calf performance or health. In conclusion, acidification to pH 4.0 - 4.5 will significantly reduce bacterial growth in milk fed to calves.

Reprogramming of germ cells into pluripotency

Primordial germ cells(PGCs) are precursors of all gametes, and represent the founder cells of the germline. Although developmental potency is restricted to germ-lineage cells, PGCs can be reprogrammed into a pluripotent state. Specifically, PGCs give rise to germ cell tumors, such as testicular teratomas, in vivo, and to pluripotent stem cells known as embryonic germ cells in vitro. In this review, we highlight the current knowledge on signaling pathways, transcriptional controls, and post-transcriptional controls that govern germ cell differentiation and de-differentiation. These regulatory processes are common in the reprogramming of germ cells and somatic cells, and play a role in the pathogenesis of human germ cell tumors.

The Potential Relationship between the Incidence of Neurodegenerative Disease and Trace Mineral Composition in the Drinking Water of Rural Residents of Ontario

Many chronic degenerative diseases have been linked to high intake of various trace and heavy metals. The presence of these compounds in drinking water may be a significant contributing factor to total dietary intake and deposition, resulting in the propagation of a disease cascade. Dairy farm families residing in rural Ontario completed a survey pertaining to the health status of the individuals living on-farm. Water samples were also collected at each location and analyzed for mineral content. Out of 200 surveys delivered to farms, 134 were returned, which formed a study group comprised of 218 adult and 230 children participants. Taking into consideration several factors, such as genetics, environment and diet, the data were analyzed for correlations between heavy metal and mineral status and the prevalence of neurodegenerative diseases. The findings from this study suggest phosphorus, potassium and magnesium concentrations may play a role in the development of neurodegenerative diseases. Total hardness and pH of water may also have an impact on the development of these diseases.

Blue and Grey Water Footprints of Dairy Farms in Kuwait

In Kuwait, dairy farming faces challenges due to its significant water demands. The current study assessed seasonal patterns of water use to estimate the blue water footprint (WF) and grey WF per kg of fat protein corrected milk (FPCM) for confined dairy farming systems in Kuwait. Blue and grey WFs were evaluated using data from three operational farms. The average blue WF (L·kg-1 FPCM) was estimated to be 54.5 ± 4.0 L·kg-1 in summer and 19.2 ± 0.8 L·kg-1 in winter. The average grey WF (generated from milk house wastewater) was assessed on bimonthly basis and determined based on its phosphate (PO4) concentration (82.2 ± 14.3 mg·L-1) which is the most limiting factor to be 23.0 ± 9.0 L·kg-1 FPCM d-1. The outcomes indicate that enhancing the performance of dairy cows and adopting alternative water management strategies can play a role in minimizing the impacts of confined dairy farming systems in Kuwait on water quality and quantity.

Fine mapping of genomic regions associated with female fertility in Nellore beef cattle based on sequence variants from segregating sires

Background:Impaired fertility in cattle limits the efficiency of livestock production systems.Unraveling the genetic architecture of fertility traits would facilitate their improvement by selection.In this study,we characterized SNP chip haplotypes at QTL blocks then used whole-genome sequencing to fine map genomic regions associated with reproduction in a population of Nellore(Bos indicus)heifers.Methods:The dataset comprised of 1337 heifers genotyped using a GeneSeek®Genomic Profiler panel(74677 SNPs),representing the daughters from 78 sires.After performing marker quality control,64800 SNPs were retained.Haplotypes carried by each sire at six previously identified QTL on BTAs 5,14 and 18 for heifer pregnancy and BTAs 8,11 and 22 for antral follicle count were constructed using findhap software.The significance of the contrasts between the effects of every two paternally-inherited haplotype alleles were used to identify sires that were heterozygous at each QTL.Whole-genome sequencing data localized to the haplotypes from six sires and 20 other ancestors were used to identify sequence variants that were concordant with the haplotype contrasts.Enrichment analyses were applied to these variants using KEGG and MeSH libraries.Results:A total of six(BTA 5),six(BTA 14)and five(BTA 18)sires were heterozygous for heifer pregnancy QTL whereas six(BTA 8),fourteen(BTA 11),and five(BTA 22)sires were heterozygous for number of antral follicles’QTL.Due to inadequate representation of many haplotype alleles in the sequenced animals,fine mapping analysis could only be reliably performed for the QTL on BTA 5 and 14,which had 641 and 3733 concordant candidate sequence variants,respectively.The KEGG“Circadian rhythm”and“Neurotrophin signaling pathway”were significantly associated with the genes in the QTL on BTA 5 whereas 32 MeSH terms were associated with the QTL on BTA 14.Among the concordant sequence variants,0.2%and 0.3%were classified as missense variants for BTAs 5 and 14,respectively,highlighting the genes MTERF2,RTMB,ENSBTAG00000037306(miRNA),ENSBTAG00000040351,PRKDC,and RGS20.The potential causal mutations found in the present study were associated with biological processes such as oocyte maturation,embryo development,placenta development and response to reproductive hormones.Conclusions:The identification of heterozygous sires by positionally phasing SNP chip data and contrasting haplotype effects for previously detected QTL can be used for fine mapping to identify potential causal mutations and candidate genes.Genomic variants on genes MTERF2,RTBC,miRNA ENSBTAG00000037306,ENSBTAG00000040351,PRKDC,and RGS20,which are known to have influence on reproductive biological processes,were detected.

Dietary Cucumis melo Reduces Markers of Muscle and Articular Inflammation Following High-intensity Exercise in Horses

We evaluated the antioxidative and anti-inflammatory potential of daily oral supplementation with a proprietary powdered Cucumis melo pulp(CMP)on exercise-induced markers of articular and muscular oxidative stress and inflammation in 12 horses.Horses performed a high-intensity exercise test immediately prior to,and then following,3 weeks of daily supplementation of 1 g powdered CMP(CMP;n=8).Controls(Co;n=8)underwent the same exercise and sampling regime but were not supplemented.Blood and synovial fluid(SF)samples were taken 24 h prior to exercise(BL),and at 1 and 24 h following exercise.Plasma and SF were analysed for prostaglandin E2(PGE2),total antioxidant status(TAS),nitrite and superoxide dismutase(SOD)activity.SF was analysed for glycosaminoglycans(GAG),and plasma was analysed for thiobarbituric acid reactive substances(TBARS).Comparisons were made using repeated measures with the initial exercise test as a covariate.There was an increase in SF SOD activity in the CMP group.Compared to Co at 1 h,CMP reduced nitrite and GAG in SF,as well as maintained plasma TAS and lymphocyte levels.At 24 h,plasma PGE2 and creatine kinase were lower in horses receiving CMP.Three weeks of supplementation with CMP reduced markers of articular and skeletal muscle oxidative stress and inflammation in response to high-intensity exercise in horses.Nutritive antioxidants may provide a useful adjunct to the daily nutrition plan of horses undergoing regular exercise training and competition.

Ferroptosis is involved in deoxynivalenol-induced intestinal damage in pigs

Background Deoxynivalenol(DON)is a widespread issue for feed and food safety,leading to animal and human health risks.The objective of this study was to determine whether ferroptosis is involved in DON-induced intestinal injury in piglets.Three groups of 21-day-old male weanling piglets(n 4,serum and small intestines were=7/group)were fed a control diet,or diet adding 1.0 or 3.0 mg DON/kg.At week collected to assay for biochemistry,histology,redox status and ferroptosis-related genes expression.In addition,the involvement of ferroptosis and the role of FTL gene in DON-induced cell death were further verified in the IPEC-J2 cells.Results Compared to the control,dietary supplementation of DON at 1.0 and 3.0 mg/kg induced different degrees of damage in the duodenum,jejunum and ileum,and increased(P<0.05)serum lipopolysaccharide concentration by 46.2%-51.4%.Dietary DON supplementation at 1.0 and(or)3.0 mg/kg increased(P<0.05)concentrations of malondialdehyde(17.4%-86.5%)and protein carbonyl by 33.1%-92.3%in the duodenum,jejunum and ileum.In addition,dietary supplemented with DON upregulated(P<0.05)ferroptotic gene(DMT1)and anti-ferroptotic genes(FTL and FTH1),while downregulated(P<0.05)anti-ferroptotic genes(FPN,FSP1 and CISD1)in the duodenum of the porcine.Furthermore,the in vitro study has demonstrated that deferiprone,a potent ferroptotic inhibitor,mitigated(P<0.05)DON-induced cytotoxicity in porcine small intestinal IPEC-J2 cells.Additionally,deferiprone prevented or alleviated(P<0.05)the dysregulation of ferroptosis-related genes(ACSL4 and FTL)by DON in IPEC-J2 cells.Moreover,specific siRNA knockdown FTL gene expression compromised the DON-induced cell death in IPEC-J2 cells.Conclusions In conclusion,this study revealed that ferroptosis is involved in DON-induced intestinal damage in porcine,and sheds a new light on the toxicity of DON to piglets.

Production systems and important antimicrobial resistant-pathogenic bacteria in poultry:a review

Economic losses and market constraints caused by bacterial diseases such as colibacillosis due to avian pathogenic Escherichia coli and necrotic enteritis due to Clostridium perfringens remain major problems for poultry producers,despite substantial efforts in prevention and control.Antibiotics have been used not only for the treatment and prevention of such diseases,but also for growth promotion.Consequently,these practices have been linked to the selection and spread of antimicrobial resistant bacteria which constitute a significant global threat to humans,ani-mals,and the environment.To break down the antimicrobial resistance(AMR),poultry producers are restricting the antimicrobial use(AMU)while adopting the antibiotic-free(ABF)and organic production practices to satisfy consum-ers’demands.However,it is not well understood how ABF and organic poultry production practices influence AMR profiles in the poultry gut microbiome.Various Gram-negative(Salmonella enterica serovars,Campylobacter jejuni/coli,E.coli)and Gram-positive(Enterococcus spp.,Staphylococcus spp.and C.perfringens)bacteria harboring multiple AMR determinants have been reported in poultry including organically-and ABF-raised chickens.In this review,we discussed major poultry production systems(conventional,ABF and organic)and their impacts on AMR in some potential pathogenic Gram-negative and Gram-positive bacteria which could allow identifying issues and opportuni-ties to develop efficient and safe production practices in controlling pathogens.

CD163双等位基因编辑猪的制备及传代

【目的】猪繁殖与呼吸综合征(porcine reproductive and respiratory syndrome,PRRS),俗称"蓝耳病",是由猪繁殖与呼吸综合征病毒(porcine reproductive and respiratory syndrome virus,PRRSV)引起的一种高致死性传染病,对世界养猪业造成了巨大的经济损失。由于PRRSV遗传变异性较大,因此国内外并未有理想疫苗能够对此病进行有效防制。Cluster of differentiation 163(CD163)是PRRSV感染猪肺泡巨噬细胞(porcine alveolar macrophage,PAM)的受体之一,研究旨在利用CRISPR/Cas9技术结合体细胞核移植技术制备CD163基因编辑的大白猪。【方法】针对猪CD163基因的第7外显子设计构建CRISPR/Cas9基因编辑载体;转染大白猪胎儿成纤维细胞,获得基因编辑阳性细胞克隆;以基因编辑细胞为核供体、体外成熟的猪卵母细胞为核受体构建克隆胚胎;胚胎移植到受体母猪生产CD163基因编辑猪,并进行后续的扩繁试验。【结果】设计的g RNA能够高效的识别靶位点。对获得的127个细胞单克隆进行PCR和测序显示,共有21个克隆发生突变,其中14个克隆为单等位基因突变或双等位基因杂合突变,7个克隆为双等位基因纯合突变。通过体细胞核移植技术,成功获得了CD163双等位基因编辑的纯合大白猪;并获得首批F1代CD163基因编辑仔猪,目前健康状态良好。随后将有更多的F1代CD163基因编辑猪陆续出生。【结论】制备的无抗性筛选标记的CD163双等位基因编辑猪,能够安全并快速地为培育抗PRRSV新品种猪提供育种材料。

运用生物能量学模型预测草鱼生长、饲料需求和污染排放

为预测不同生长阶段草鱼生长性能、饲料需求量和污染排放量,提高草鱼投喂管理水平,本研究运用特定增长率(SGR)、日增长率(DGC)、日均增重(ADG)和热积温系数(TGC)等生长模型计算草鱼在不同生长阶段的生长速率,并通过计算定期采样中实际观测值和预测值最小残差平方和法选出最优生长模型。饲料需求模型通过估算鱼类消化能需求量决定,根据能量收支原理,通过计算鱼体储积能(RE)、基础代谢能(He E)、摄食热增能(Hi E)以及尿液和鳃的代谢能(UE+ZE),来估算草鱼的消化能,再根据所用饲料的消化能含量来确定草鱼对饲料的需求量。草鱼污染物排放主要采用营养物质平衡法计算。在模型验证时,以粗蛋白分别为33%、28%、23%的饲料投喂不同生长阶段的草鱼,将草鱼体质量和饲料系数(FCR)的模型预测值与实际观测值进行比较。结果显示,与其他生长模型(SGR、ADG、DGC)相比,调整后的TGC模型能更精确预测草鱼的生长情况;草鱼体质量和FCR预测值与观测值之间显著相关;每生产1 t鱼(体质量为0.5~2 500 g),其消化能需求量约为1.55×107 k J,消耗1 t饲料或生产1 t鱼所排放的总固态污染物分别为440和623 kg。研究表明,该复合性营养模型可以有效地估计实际养殖中草鱼生长、饲料需求量和污染物排放量,有望为草鱼差异化上市、节省饲料成本、减少饲料浪费以及养殖场的污染评价提供有效的预判工具。

基于生物能量学原理构建异育银鲫生长、饲料需求和污染排放模型

为构建鱼类生长、饲料需求和污染排放预测模型,提高鱼类精准投喂管理水平,通过收集大量文献中异育银鲫(Carassius auratus gibelio)生长数据(异育银鲫体重0.25—550 g),运用特定增长率(SGR)、日增长率(DGC)、日均增重(ADG-Linear)、热积温系数(TGC)和校正后的热积温系数(Rev.TGC)等生长模型计算其生长速率,并通过计算实际观测值和预测值最小残差和法选出最适生长模型。结果发现,在用TGC模型计算其生长率时,异育银鲫在其生长周期中含有3个异速生长点,根据该点的位置,可以将异育银鲫的生长周期分为3个阶段:0.25—13.1 g(第一阶段)、13.1—172.8 g(第二阶段)、>172.8 g(第三阶段)。在这3个阶段中调整后的TGC模型比其他模型(SGR、DGC、ADG)可以更好地预测实际养殖中异育银鲫的生长性能。鱼类在不同的生长阶段对饲料的需求量由消化能决定,通过计算鱼体储积能、基础代谢能、热增能以及尿液和鳃的代谢能,可以估算异育银鲫的消化能,从而确定其饲料需求量。经估算,对于体重为0.25—506 g的异育银鲫,每生产1 kg鱼,其消化能需求量约为1.94×104 k J。在模型验证时,以粗蛋白分别为43%、37%、31%的饲料投喂不同生长阶段的异育银鲫,并利用营养物质平衡法估计废物排放量。研究发现,实测值与模型预测值显著相关。模型可以在异育银鲫实际养殖过程中,有效预估某个生长阶段异育银鲫的体重、所需要的饲料量以及氮、磷污染物排放量,有望为异育银鲫差异化上市、节省饲料成本、减少饲料浪费以及养殖场的污染评价提供有效的预判工具。

Traditional and emerging Fusarium mycotoxins disrupt homeostasis of bovine mammary cells by altering cell permeability and innate immune function

High incidence of traditional and emerging Fusarium mycotoxins in cereal grains and silages can be a potential threat to feed safety and ruminants.Inadequate biodegradation of Fusarium mycotoxins by rumen microflora following ingestion of mycotoxin-contaminated feeds can lead to their circulatory transport to target tissues such as mammary gland.The bovine udder plays a pivotal role in maintaining milk yield and composition,thus,human health.However,toxic effects of Fusarium mycotoxins on bovine mammary gland are rarely studied.In this study,the bovine mammary epithelial cell line was used as an in-vitro model of bovine mammary epithelium to investigate effects of deoxynivalenol(DON),enniatin B(ENB)and beauvericin(BEA)on bovine mammary gland homeostasis.Results indicated that exposure to DON,ENB and BEA for 48 h significantly decreased cell viability in a concentration-dependent manner(P<0.001).Exposure to DON at 0.39μmol/L and BEA at 2.5μmol/L for 48 h also decreased paracellular flux of FITC-40 kDa dextran(P<0.05),whereas none of the mycotoxins affected transepithelial electrical resistance after 48 h exposure.The qPCR was performed for assessment of expression of gene coding tight junction(TJ)proteins,toll-like receptor 4(TLR4)and cytokines after 4,24 and 48 h of exposure.DON,ENB and BEA significantly upregulated the TJ protein zonula occludens-1,whereas markedly downregulated claudin 3(P<0.05).Exposure to DON at 1.35μmol/L for 4 h significantly increased expression of occludin(P<0.01).DON,ENB and BEA significant downregulated TLR4(P<0.05).In contrast,ENB markedly increased expression of cytokines interleukin-6(IL-6)(P<0.001),tumor necrosis factorα(TNF-a)(P<0.05)and transforming growth factor-β(TGF-β)(P<0.01).BEA significantly upregulated IL-6(P<0.001)and TGF-β(P=0.01),but downregulated TNF-α(P<0.001).These results suggest that DON,ENB and BEA can disrupt mammary gland homeostasis by inducing cell death as well as altering its paracellular permeability and expression of genes involved in innate immune function.

Growth performance,gastrointestinal weight,microbial metabolites and apparent retention of components in broiler chickens fed up to 11%rice bran in a corn-soybean meal diet without or with a multi-enzyme supplement

We investigated the effects of adding up to 11% rice bran(RB) in corn-soybean meal diets fed to broiler chickens without or with a multi-enzyme supplement(MES). The MES supplied xylanase, b-glucanase invertase, protease, cellulase, a-amylase and mannanase with targeted activity of 2,500, 300, 700, 10,0001,200, 24,000, and 20 U/kg of feed, respectively. The study used a two-phase feeding program(starter d 0 to 24; finisher, d 25 to 35) with RB added at 5% and 11%, respectively creating 4 diets in each phase Diets were iso-caloric and iso-nitrogenous and contained phytase(500 FTU/kg) and TiO_2 as a digestibility marker. Three hundred and sixty d-old male Ross 708 broiler chicks were placed in cages based on BW(15 birds/cage) and allocated to 4 diets(n = 6). Birds had free access to feed and water. Body weight and feed intake were recorded. Excreta samples were collected 3 d prior to the end of each phase for apparent retention(AR) of components. Samples of birds were sacrificed on d 24 and 35 for gut weight and ceca digesta for organic acid content. There was no interaction(P > 0.10) between RB and MES on BWG and FCR in starter or finisher phase. In finisher phase, birds fed MES had better BWG(961 versus 858 g) and FCR(1.69 versus 1.86) than birds fed non-MES diets(P < 0.01). Feeding RB reduced(P = 0.02) BWG in finisher phase resulting in lower d 35 BW. Birds fed RB had higher(P 0.01) gizzard weight on d 24 and 35 than non-RB birds. An interaction(P 0.01) between RB and MES on concentrations of propionic and iso-butyric acids in ceca digesta showed that MES reduced these acids in non-RB diet. The AR of gross energy was higher(P < 0.02) for MES versus non-MES birds in starter and finisher phases. In conclusion independently, RB increased gizzard weight and reduced final BW whereas MES improved growth and energy utilization.

Impact of xylanases on gut microbiota of growing pigs fed corn-or wheat-based diets

This study investigated the effects of xylanase supplementations with cereal-based diets on nutrient digestibility and gut microbiota of growing pigs. A total of 96 individually penned pigs(initial BW = 22.7 ± 0.65 kg) were allotted to 12 treatments and subjected to a completely randomized block design experiment. Pigs in each treatment were fed an isocaloric wheat-based or corn-based diet with or without 1 of 5 types of xylanase supplements(XA, XB, XC, XD, XE). On d 42, all piglets were euthanized to obtain ileal and cecal digesta for microbial analysis, which involved high-throughput sequencing of the V1 - V3 regions of 16 S rRNA gene. Corn-and wheat-based diets differed(P < 0.05) in digestion characteristics. Dietary treatments affected the alpha-and beta-diversities of microbiota in the cecum but not in the ileum. The wheat-based diet increased(P < 0.05) alphadiversity and clustered separately(P < 0.05) compared with the corn-based diet. Wheat-based diet also promoted the relative abundance of genus(g.) Succinivibrio while corn-based diet promoted the proportion of family(f.) Veillonellaceae in the community. Among xylanases, only XC within the wheat-based diet altered(P < 0.05) the beta-diversity of the cecal microbiota compared with control. For each cereal-based diet and compared with the controls, xylanase treatments affected(P < 0.05) the proportions of 5 bacterial taxa in the ileum(f. Peptostreptococcaceae, order [o.]Streptophyta, f. Clostridiaceae, g. Clostridium and g. Streptococcus) and 8 in the cecum(g. Lactobacillus,g. Streptococcus, class [c.] Clostridia, f. Clostridiaceae, g. Megasphaera, g. Prevotella, g. Roseburia and f.Ruminococcaceae). Network analysis showed that across diets under control treatments, Bacteroidetes was the most influential phylum promoting cooperative relationships among members of the ileum and cecum microbiota. Xylanase treatment, however, reduced the influence of Bacteroidetes and promoted a large number of hub taxa majority of which belonged to the Firmicutes phylum. To maximize the efficiency of xylanase supplementation, our data suggest that xylanase C originated from Bacillus subtilis was more effective when applied to wheat-based diets, while xylanase A originated from Fusarium verticillioides was more beneficial when applied to corn-based diets.

Cage type and mineral nutrition had independent impact on skeletal development in Lohmann LSL-Lite pullets from hatch to 16 weeks of age

The effects of rearing cage type and dietary Ca,available P and vitamin D_(3)(VitD_(3))on body and skeletal development were studied.A total of 3,420 Lohmann LSL-Lite day-old chicks were reared in conventional(CON)or furnished cages(FUR)to 16 wk of age.Initially,40 and 150 chicks/cage were placed in CON and FUR and transitioned to 20 and 75 chicks/cage at 8 wk of age,respectively.Three diets:Diet 1,Diet 1.5 and Diet 2 were formulated to meet nutrient specifications with Diet 1.5 and Diet 2 containing 1.5 and 2 times more Ca,P and VitD_(3)than Diet 1,respectively.Diets were allocated within cage type to give 6 replicates and fed in 3 feeding programs:starter,grower and developer.At 4,12 and 16 wk of age,BW was recorded,and femur,tibia and blood samples for bone quality and related parameters.There were no interactions(P>0.05)of cage type,diet and pullet age on BW,plasma Ca and inorganic P,femur and tibia morphometry,mineral density(MD),breaking strength(BS)and ash concentration(AC).Concentration of Ca,P and VitD_(3)linearly decreased BW(P<0.001),relative femur(P=0.010)and tibia weight(P=0.013).A quadratic increase on femur MD(P=0.03)and BS(P=0.026)was observed with dietary concentration of Ca,P and VitD_(3).Femur(P=0.031)was longer for CON than FUR pullets,however,femur for FUR pullets had higher(P=0.003)AC.Cage had no effect(P≥0.415)femoral MD and BS.Pullets reared in FUR cages exhibited higher tibial MD(P=0.015),BS(P=0.071),AC(P<0.01)and whole-body mineral content(P<0.01).In conclusion,cage type and diets showed independent effect on femur and tibia quality with FUR pullets exhibiting enhanced indices of mineralization.Feeding pullets twice the recommended Ca,P and VitD_(3)decreased BW,relative weight of leg bone but enhanced femoral strength with no effects on tibia attributes.

Ovine hippocampal mRNA expression in offspring from dams supplemented with fishmeal and stress challenged in late pregnancy with endotoxin

Previous research has shown that adulthood disease can be attributed to stress events that occur during gestation. The objective of the present study was to determine whether maternal stress during late pregnancy, using a bacterial endotoxemia model, causes changes in hippocampal mRNA expression of candidate genes related to hypothalamic-pituitary-adrenal axis(HPAA) regulation in sheep. This study also sought to investigate whether maternal diets supplemented with fishmeal(FM) rich in omega-3 polyunsaturated fatty acids(PUFAs) offer protection to the fetus when subjected to maternal endotoxin stress. Using RT-qPCR, relative mRNA expression was assessed in both fetal lambs and 6-month-old lambs from dams supplemented with soybean meal(SM) or FM and challenged with either endotoxin or saline. From this it was found that fetal mineralocorticoid receptor(MR) gene expression had a tendency to be altered during endotoxin challenge, however, in the 6-month-old offspring, MR and glucocorticoid receptor(GR) gene expression were differently altered across treatment groups. These results suggest that gene regulation within the hippocampus is altered into adulthood by maternal endotoxin stress and that dietary supplementation affects outcome.