发酵饲料对巴民杂交猪肉质性能影响的研究

为了研究发酵饲料对巴民杂交猪肉质性能的影响,试验将12头体重60 kg的巴民杂交猪随机分成2组,每组6头,分别饲喂益生菌制备发酵饲料(试验组)和常规饲料(对照组)70 d至体重110 kg左右,对试验猪只的背最长肌肉色、系水力、滴水损失和肌内脂肪含量指标进行了研究。结果表明:与对照组肉品相比,试验组的亮度值(L*值)和黄度值(b*值)低于对照组,红度值(a*值)高于对照组;试验组与对照组相比系水力提高了0.44个百分点,试验组与对照组相比滴水损失降低了0.07个百分点,试验组与对照组相比肌内脂肪含量提高了0.14个百分点,但差异不显著(P>0.05),试验组在肉色、系水力、肌内脂肪等指标方面皆有所改善。试验结果说明饲喂发酵饲料能够在一定程度上提高巴民杂交猪肉品肉质,对其能够更好地满足人们对优质肉品需求具有重要意义。

种猪育种关键技术研究进展

在生猪养殖过程当中,种猪育种是一个非常重要的环节。提高种猪育种水平,可以有效提高生猪养殖的经济效益。因此文章基于育种目标选定,从常规育种技术、分子育种技术、人工授精技术三大方面分析种猪育种的关键技术研究进展。

全方位入手实现无抗、替抗养猪

抗生素是由微生物(包括细菌、真菌、放线菌属)或高等动植物在生命过程中所产生的,具有抗病原体或其他活性的,一类次级代谢产物,能对抗在人或动物体内的致病菌等病原体,可治疗大多数细菌、立克次体、支原体、衣原体、螺旋体等微生物感染导致的疾病。现临床常用的抗生素有微生物培养液中提取物以及用化学方法合成或半合成的化合物,目前已知天然抗生素不下万种。

生长育肥猪常见疾病的临床表现及防控

随着养殖水平不断提高以及居民对猪肉制品消费和需求的不断增加,我国生猪养殖规模的不断扩大,目前生猪存栏量、出栏量均较前期有所提高。我国养猪业在不断发展的同时,也在面临着前所未有的困难和挑战,其中对养猪业和养殖者来说最大的难题,就是猪病的种类不断增加,以及随之不断提升的预防和治疗的难度与成本。特别是对于生长育肥猪来说,一旦患病,便会给养殖者带来巨大的经济损失。文章对目前生猪养殖业中生长育肥猪常见且危害较大的几种疾病的临床表现和防控进行了简要综述。

Research Progress on the Effect of Aflatoxin on Poultry Immunization

Aflatoxins( AFs) are a major pollution source of grain pollution and are secondary metabolites produced by Aspergillus flavus and A.parasiticus,which are one of the most toxic and carcinogenic substances.Feeding animals with aflatoxin-contaminated food can cause toxicosis,acute liver injury or liver cancer in animals,and also can cause multiple organ damage,decline in production performance and disease resistance,even death,which brings great economic losses to animal husbandry.In addition,AFs can do great harm to the human body.When the body ingests large amounts of AFs,it may suffer from acute poisoning and acute liver damage; and AFs can cause chronic poisoning of the body with continuous intake of trace AFs.This paper briefly analyzed the effect of AFs on the structure and function of poultry immune organs,immune gene expression,immunosuppression and so on.

Glutamate and aspartate alleviate testicular/epididymal oxidative stress by supporting antioxidant enzymes and immune defense systems in boars

Several potential oxidative agents have damaging effects on mammalian reproductive systems.This study was conducted to investigate the effects of glutamate(Glu)and aspartate(Asp)supplementation on antioxidant enzymes and immune defense systems in the outer scrotum of boars injected with H2O2.A total of 24 healthy boars were randomly divided into 4 treatment groups:control(basal diet,saline-treated),H2O2(basal diet,H2O2-challenged outer scrotum(1 m L kg^–1 BW)),Glu(basal diet+2%Glu,H2O2-challenged),and Asp(basal diet+2%Asp,H2O2-challenged).Our results showed that both Glu and Asp supplementation improved testicular morphology and decreased the genital index in the H2O2-treated boars.Glu and Asp administration increased the antioxidant enzyme activities and affected the testicular inflammatory cytokine secretion but had no effect on sex hormone levels.Furthermore,the m RNA expression of CAT,Cu Zn SOD,and GPx4 was altered in the testes and epididymis of boars treated with Asp and Glu.Glu and Asp supplementation also modulated the expression of TGF-β1,IL-10,TNF-α,IL-6 and IL-1βin the testis and epididymis.These results indicate that dietary Glu and Asp supplementation might enhance antioxidant capacity and regulate the secretion and expression of inflammatory cytokines to protect the testes and epididymis of boars against oxidative stress.

Glutamine in suppression of lipopolysaccharide-induced piglet intestinal inflammation:The crosstalk between AMPK activation and mitochondrial function

The study was conducted to investigate the regulatory mechanism of glutamine(Gln)on intestinal inflammation in an Escherichia coli lipopolysaccharide(E.coli LPS)-induced in vivo and in vitro models.Piglets(n=8)weaned at 21 d of age were fed a basal diet(control and LPS groups)or 1%Gln diet(Gln t LPS group)ad libitum for 4 weeks.On d 22,24,26 and 28,piglets in the LPS and Gln t LPS groups were intraperitoneally injected with E.coli LPS.Intestinal porcine epithelial cells(IPEC-J2)(n=6)induced by LPS were used to assess related mechanisms and compound C was used to inhibit adenosine 50-monophosphate-activated protein kinase(AMPK)activity.Our current results showed that compared with the LPS treatment,the Gln t LPS treatment had better growth performance and greater villus height(P<0.05),and the Gln t LPS treatment reduced the rate of diarrhea by 6.4%(P<0.05);the Gln t LPS treatment decreased serum tumor necrosis factor(TNF-ɑ),interleukin-6(IL-6),Kt,cortisol and insulin levels,whereas increased(P<0.05)serum immunoglobulin M and epidermal growth factor levels;the Gln t LPS treatment increased(P<0.05)the expression of aquaporins and AMPK pathwayassociated targets in the jejunum and ileum of piglets,whereas decreased the expression of ion transporters(P<0.05).The in vitro results showed that 4 mmol/L Gln administration could inhibit(P<0.05)cell apoptosis and interleukin-1b(IL-1b),IL-6 and TNF-ɑsecretion in LPS-induced IPEC-J2 cells,promote(P<0.05)mitochondrial respiratory metabolism and increase(P<0.05)the number of mitochondria and mitochondrial membrane potential.The activity of AMPK was elevated by 70%to 300%in Gln-treated IPEC-J2 cells under LPS challenge or normal conditions.Our results indicate that pre-administration of Gln to piglets suppresses intestinal inflammation by modulating the crosstalk between AMPK activation and mitochondrial function.

Crosstalk between trace elements and T-cell immunity during early-life health in pigs

With gradual ban on the use of antibiotics, the deficiency and excessive use of trace elements in intestinal health is gaining attention. In mammals, trace elements are essential for the development of the immune system, specifically T-cell proliferation,and differentiation. However, there remain significant gaps in our understanding of the effects of certain trace elements on T-cell immune phenotypes and functions in pigs. In this review, we summarize the specificity, development, subpopulations, and responses to pathogens of porcine T cells and the effects of functional trace elements(e.g., iron, copper, zinc, and selenium) on intestinal T-cell immunity during early-life health in pigs. Furthermore, we discuss the current trends of research on the crosstalk mechanisms between trace elements and T-cell immunity. The present review expands our knowledge of the association between trace elements and T-cell immunity and provides an opportunity to utilize the metabolism of trace elements as a target to treat various diseases.