肉用山羊营养需要量的研究进展

世界上的山羊数量虽然很多，但有关山羊的营养需要量的研究迄今为止很少，至于肉用山羊营养研究的文献资料就更少了。应用于山羊营养需要量的大部分数据来源于牛和绵羊的营养参数。本文着重就山羊的消化代谢特点、能量、蛋白质、维生素及矿物质营养需要量的研究进展及现状作了阐述。     

山羊营养需要量的研究进展

世界上的山羊数量虽然很多,但有关山羊的营养需要量的研究迄今为止很少,至于山羊营养研究的文献资料就更少了。应用于山羊营养需要量的大部分数据来源于牛和绵羊的营养参数。本文着重就山羊的消化代谢特点、能量、蛋白质、维生素及矿物质营养需要量的研究进展及现状作了阐述。     

种公牛营养需要研究进展

种公牛饲养标准是根据种公牛营养需要量和饲料成分组成而定的,是指导种公牛饲养的依据。文章综述了国内外影响种公牛精液质量的营养因素及种公牛营养需要量的研究进展,为我国种公牛生产水平的进一步提高提供科学依据。     

蛋鸡产蛋期粗蛋白质及氨基酸需要量的研究

蛋白质是生命过程中的重要物质,是组成机体结构物质、体内代谢活性物质的主要成分,是组织更新、修补的原料,具有重要的营养生理作用[1,2]。长期以来,动物营养学家都致力于理想蛋白氨基酸模式的研究,预测蛋白水平对蛋鸡生产性能的影响[3],特别是在蛋白质和氨基酸需要量的研究中广泛结合数学模型[4],对畜禽体重或组织器官等进行动态的描述和分析,从而预测畜禽在实际生长条件下的营养需要量,以建立最佳饲喂方案[4]。     

绒山羊非生绒期日粮铜水平对纤维降解率的影响

国内外对山羊营养的研究主要集中在能量和蛋白质(包括氨基酸)上,而对矿物质元素研究很少。国际上对山羊矿物质营养的研究远落后于牛和绵羊,山羊矿物质元素供给量大都借鉴了牛和绵羊的资料。铜是动物一种必需矿物元素,参与造血、骨骼构成、被毛色素的沉着和脑细胞及脊髓的质化,并且是多种酶的组成成分和激活剂。日粮中铜供给不足或缺乏时,会使毛色变浅、毛质下降。此外,铜对于维持反刍动物瘤胃微生物区系也是必需的。本试验的目的是通过研究日粮不同的铜添加水平对绒山羊日粮纤维降解率的影响,确定绒山羊日粮铜的适宜添加水平,为进一步研究该…     

肉用山羊营养需要量的研究进展

本文综述了肉用山羊的饲料采食量，蛋白质、能量、矿物质及维生素等营养需要量的研究进展及现状。     

马头山羊生长发育特性的调查研究

对马头山羊主产区鄂西北地区自然生长的不同年龄、不同性别马头山羊的体重、体尺进行测量、统计,通过对马头山羊体尺、体重变化的分析,研究其生长发育特性,为马头山羊的品种应用和生产提供科学依据。     

盐度对水产动物体组成与组织结构的影响

综述了盐度对水产动物的体组成、风味、营养需求、血液成分以及组织结构的影响,不仅为满足不同盐度下水产动物的营养需求、判定水产动物的适应状况提供科学依据,而且对改善低盐度下肌体风味具有重要意义。     

PSMD9对山羊前体脂肪细胞脂质沉积的调控作用研究

旨在克隆山羊PSMD9基因序列并对其进行生物信息学分析，检测PSMD9在山羊各组织中的表达情况和肌内前体脂肪细胞不同分化时期的表达水平，并进一步揭示过表达和干扰PSMD9基因对山羊肌内前体脂肪细胞脂质沉积的影响。本研究以1周岁健康简州大耳羊公羊(n=12)为试验对象，采用T-A克隆技术获得山羊PSMD9基因序列，进行生物信息学分析，并通过双酶切方法构建PSMD9过表达载体。利用脂质体转染在山羊肌内脂肪细胞中过表达PSMD9,小干扰RNA(small interfering RNA, siRNA)干扰PSMD9表达。通过油红O染色法观察PSMD9对脂滴形成的影响，GPO-Trinder酶学反应检测甘油三酯含量；同时利用实时荧光定量PCR(RT-qPCR)检测PSMD9在山羊不同组织中的表达水平和肌内前体脂肪细胞不同分化时期的表达水平。结果，获得山羊PSMD9基因核苷酸序列763 bp,其中5′UTR 67 bp, CDS区564 bp, 3′UTR 132 bp,编码187个氨基酸残基；山羊PSMD9基因在肝脏中的表达量最高，在脾脏中表达量最低，在诱导分化前4 d其表达水平随着山羊前体脂...     

饲料级磷酸盐的生物学评价

磷不仅是家禽日粮中必需的营养成分，而且其重要程度仅次于能量和蛋白质，因而研究家禽对磷需要量和利用率的文献很多，在这些研究中多采用体重和胫骨灰分含量作为评价磷源的指标。人们在研究中发现，不同磷源中磷的相对生物学利用率是不同的。一般情况下，磷酸二氢钙具有...     

光照和埋植褪黑激素对非生绒期内蒙古白绒山羊体成分的影响及应用

本文从体成分的角度研究了褪黑激素对内蒙古白绒山羊营养分配的影响,研究结果显示光照时间和埋植褪黑激素显著影响绒山羊的有关激素水平,进而影响体成分组成。随着光照时间的缩短,绒山羊的体脂肪含量增加,体蛋白含量减少;光照相同条件下,埋植褪黑激素组的体脂肪含量高于不埋植组,体蛋白含量低于不埋植组,短光照和埋植褪黑激素之间有显著(P<0.01)的互作效应。证明了光照和褪黑激素在动物营养分配中的作用,为褪黑激素在生产实践中的合理应用提供理论依据。     

Body growth and plasma concentrations of metabolites and metabolic hormones during the pubertal period in female Shiba goats

It has been shown in various species that the onset of puberty is closely associated with body growth and nutritional state rather than age. The present study was conducted to determine the timing of puberty and to clarify body growth and metabolic changes around the pubertal period in female Shiba goats. Blood samples were collected between 10 to 38 weeks of age from 12 female goats, and plasma concentrations of progesterone, metabolites (glucose, nonesterified fatty acid, ketone body and acetic acid) and metabolic hormones (insulin and insulin-like growth factor-I (IGF-I)) were analyzed. Physical parameters (body weight, withers height and body length) were also measured at the blood sampling. The week when plasma progesterone concentrations first exceeded 1.0 ng/ml was designated as the onset of puberty. The results showed that the average age of the onset of puberty was 27.0 +/- 0.9 (mean +/- SEM) weeks in female Shiba goats. When the goats reached puberty, the average values of body weight and goat body mass index ((body weight (kg)/withers height (cm)/body length (cm)) x 10(3)) were 12.2 +/- 0.5 kg and 5.7 +/- 0.2, respectively. No particular change associated with puberty was apparent for plasma concentrations of the metabolites examined. Plasma insulin concentrations were maintained at lower levels until the onset of puberty, and then they began to gradually increase. Plasma IGF-I concentrations began to gradually increase 1 to 4 weeks before the onset of puberty and this increase continued throughout the peripubertal period. These results imply that IGF-I acts as a peripheral nutritional signal to trigger the onset of puberty in Shiba goats.     

Assessment of body fat in the pony: part I. Relationships between the anatomical distribution of adipose tissue, body composition and body condition

Reasons for performing study: Evaluation of equine body fat content is important for nutritional and clinical purposes. However, our understanding of total body fat and its regional distribution in the body is sparse. Currently, body fat evaluation relies on the subjective assessment of body condition score (BCS), which has never been validated against ‘gold standard’ chemical analysis or dissection measurements in ponies. Objectives: To define the relationships between subjective (BCS), objective (morphometric) indices of body fat and ‘gold standard’ measurements of actual body composition. Hypotheses: BCS and morphometry offer valid, noninvasive methods for determination of body fat in equids. Methods: Seven mature (mean ± s.e. 13 ± 3 years, 212 ± 14 kg, BCS 1.25–7/9), Welsh Mountain pony mares, destined for euthanasia (for nonresearch purposes), were used. For all ponies, body mass (BM), BCS and various morphometric measurements were recorded. Following euthanasia, all ponies were systematically dissected. Discrete white adipose tissue (WAT) depots were independently described. Gross, body chemical composition was determined by proximate analyses. Results: Total somatic soft tissues increased linearly (r²= 1.00), whereas body WAT content (1–26% live BM) increased exponentially (r²= 0.96), with BCS. WAT was equally distributed between internal and external sites in all animals irrespective of BCS. Nuchal fat was a poor predictor of total WAT (r²= 0.66). Periorbital WAT did not alter with BCS (r²= 0.01). Heart girth:withers height and ultrasonic retroperitoneal fat depth were closely associated with total, chemically‐extracted lipid which comprised 1–29% live BM (r²= 0.91 and 0.88, respectively). Conclusions and potential relevance: The exponential relationship between BCS and total body WAT/lipid suggests that BCS is unlikely to be a sensitive index of body fat for animals in moderate‐obese states. Morphometric measurements (body girths and retroperitonel fat depth) may be useful to augment subjective BCS systems.     

MEASUREMENT OF BODY COMPOSITION IN CATS USING COMPUTED TOMOGRAPHY AND DUAL ENERGY X‐RAY ABSORPTIOMETRY

Dual energy X‐ray absorptiometry (DEXA) is a reference method for assessing body composition but is seldom `accessible in veterinary settings. Computed tomography (CT) can provide similar body composition estimates and we propose that it can be used in body composition studies in animals. We compared CT and DEXA data from 73 healthy adult neutered domestic cats. Three approaches for measuring adipose tissue percentage from full‐body CT scans were explored. By examining the frequency distribution of voxels by Hounsfield unit (HU) value, it is possible to calculate a fat index (Fat%) that is in close agreement with the fat percentages obtained from DEXA scans. Fat% values obtained by the best of the methods had a mean difference of 0.96% (95% confidence interval 0.33–1.59%) from the DEXA results. Fat% obtained by the other two methods were characterized by good correlation but poor agreement and in one of the methods, the difference between the values from the two modalities was proportional to their mean. By using CT, it is possible to obtain body composition estimates that are in close agreement with those available using DEXA. While the significance of individual Fat% measurements obtained from CT can be difficult to interpret and to compare between centers, CT can contribute to research studies concerned either with nutrition or with obesity‐related disorders.     

Exploiting the effect of dietary supplementation of small ruminants on resilience and resistance against gastrointestinal nematodes

This paper focuses on targeted nutritional supplementation as a means to reduce the requirement for chemotherapeutic control of gastrointestinal nematode infection of small ruminants and considers the limitations to practical application. Supplementary feeding, particularly with additional dietary protein, can assist resilience to infection during times when metabolic resources are being directed towards dealing with the pathophysiological effects of infection and away from production of meat, milk and fibre. Substantial experimental evidence from studies of both sheep and goats supports this hypothesis particularly in relation to young lambs and kids after weaning and in ewes around parturition. In addition, nutritional supplementation frequently increases resistance to infection, as indicated by decreased faecal worm egg counts and worm burdens. As a result, supplementation has the potential to reduce the requirement for anthelmintic treatment. Practical application of this knowledge can, however, be quite complex in many small ruminant production systems. In general, strategic supplementation should target those times when nutrient requirements are greatest and provide those nutrients which are deficient whether protein, energy, minerals or trace elements. Complexity arises when we consider that nutrient requirements will differ between localities for different species and breed of host, at different stages of growth and reproduction, with differing seasonal availability of forage, with different species of nematodes and different levels of established infections and exposure to infective stages. As a starting point, the provision of nutrients to optimize rumen function and animal performance in the particular production system should assist in maintaining resilience to nematode infection. Provision of nutrients in excess of this requirement, if economically feasible, may yield further benefits in some situations and reduce the need for alternative control measures for gastrointestinal nematode parasites.     

Analysis on Growth and Development Pattern of Holstein Cows in Changji Area of Xinjiang

The aims of this study were to understand the relationship between the indexes of body size and body weight in Holstein cows, and the variation pattern of body size and body weight of different age stages of Holstein cows in Changji area of Xinjiang were analyzed.This study based on the measurement record of the body size and body weight of 2 972 Holstein cows of different age stages from 2012 to 2013 in Changji area of Xinjiang, obtained the body size index of different age stages, and mapped out the cumulative growth curve, absolute growth curve and relative growth curve;At the same time, carried on a correlation analyses between each body size index and body weight of Holstein cows.The results showed that along with the increase of age, body size index and body weight of Holstein cows were increasing;At the age of 1 to 3, the growth and development were rapid, it was the most important period for the growth and development of cattle.The correlation coefficients among body height, body length, chest circumference, cannon circumference and body weight were reached significant level (P< 0.01).It was important to pay special attention to breeding management of Holstein cow before three years old, and ensured its nutritional requirements in order to achieve the best physical condition in the process of breeding.     

Reproductive and productivity traits of goats grazing Acacia cyanophylla Lindl. with and without daily PEG supplementation

A grazing experiment, conducted for 90 days compared the effect of polyethylene glycol (PEG) supplementation on postpartum reproductive traits and productivity of suckling goats grazing Acacia cyanophylla Lindl. A total of 54 native adult goats (34.4 ± 5.49 kg) were randomly allocated, 24 h after kidding, to 2 treatment groups balanced for age and the number of reared kids. Goats in both treatment groups designed C and PEG grazed in acacia for approximately 5 h every day and received each on daily basis 0.3 and 0.4 kg of hay and concentrate respectively. In addition, goats in treatment PEG were initially supplemented with 10 g/day of PEG and this supplement was then increased to 20 g /goat/day over the last 60 days of the trial. Goats receiving PEG tended (P > 0.05) to spend more time browsing acacia than those in treatment C. There were no treatment effects on live weight change of the goats, growth of their kids until 90 days of age or composition of their milk in terms of fat, protein and urea contents. Similar proportions of 74.1 and 77.8% of goats resumed postpartum ovulation with a mean ovulation rate of 1.50 ± 0.61 and 1.67 ± 0.47 (P > 0.05) in respectively the PEG and C treatments. PEG supplementation was associated with an increase (P < 0.05) in ovulation rate at the second postpartum ovulation occurring approximately 27 days after the application of the nutritional treatments (1.76 ± 0.60 versus 1.25 ± 0.45); 9 of the 13 goats ovulating in the PEG treatment were bearing more than one corpus lutuem in comparison to only 3 out of 12 females in the C group (P < 0.05). The likely increased availability of proteins in the PEG receiving goats could explain their higher ovulation rate.     

新疆昌吉地区荷斯坦奶牛生长发育规律分析

试验旨在分析新疆昌吉地区不同年龄阶段荷斯坦奶牛体尺、体重变化规律,了解荷斯坦奶牛体尺、体重指标之间的相关性。本研究对新疆昌吉地区测定的2012~2013年2 972头次不同年龄阶段的荷斯坦奶牛体尺、体重记录进行处理得出各年龄阶段的体尺指数,分别绘制了累积生长曲线、绝对生长曲线和相对生长曲线;并对荷斯坦奶牛各体尺指标与体重进行了相关性分析。结果表明,荷斯坦奶牛体尺、体重随着年龄的增加均呈递增趋势,在1~3岁时生长发育迅速,3岁以后,其生长速度和生长强度逐渐下降;体高、体长、胸围、管围和体重间的相关系数均达到极显著水平(P< 0.01)。在实际生产中,要特别注意荷斯坦奶牛3岁以前的饲养管理,保证其营养需求以达到最佳生理状态。     

中国地方黄羽肉鸡与隐性白羽肉鸡二元杂交效果分析

本试验设计了2个地方黄羽肉鸡品种与隐性白羽肉鸡的杂交组合,测定比较了不同周龄的体重和屠体性状。实验结果表明,地方品种与隐性白羽肉鸡的杂交后代生长速度极显著高于地方品种纯繁后代;石歧杂和北京油鸡与隐性白羽肉鸡杂交后代间生长速度无显著差异,且北京油鸡比石歧杂表现更强的杂种优势;杂交及纯繁后代在屠体性状上有一定的差异。     

南江黄羊杂交改良本地黄羊母羊的生长发育效果分析

选择南江黄羊、南江黄羊×本地黄羊的F1代黄羊以及本地黄羊母羊的生长发育资料,分别对其体重、日增重和体尺等指标进行对比分析,研究南江黄羊对杂交改良效果。结果表明,F1代黄羊体重明显高于本地黄羊（P〈0.05）;F1代黄羊与本地黄羊初生-6月龄日增重差异极显著（P〈0.01）,初生-12月龄日增重差异显著（P〈0.05）;F1代黄羊与本地黄羊6月龄体长、24月龄胸围差异显著（P〈0.05）,12月龄体高差异极显著（P〈0.01）。试验结果显示,南江黄羊杂交改良本地黄羊母羊在生长早期效果明显,显著高于本地黄羊。