短角牛与秦川牛杂交效果观察

按照省上黄改总体方案,我县从1988年引进英国短角红牛与秦川牛进行杂交改良,推广乳、肉、役兼用型品种,使养牛业从役用向多用型发展,提高养牛的经济效益。3年来,应用短角红牛共配黄牛2785头,现已产犊牛2220余头,占黄牛总数的6.5％,实践证明,短秦F_1牛具有生长发育快,生产性能高,适应性强,经济效益高等优点;18月龄在饲养水平偏低条件下,平均体重321kg,比秦川牛     

农业产业结构调整之我见--"黄牛奶改”应全面推广

秦川牛肉质好,抗逆性强,易饲养,深受群众喜受,是优良的黄牛品种.但在当前经济发展的形势下,秦川牛饲养周期长,经济效益低,很不适应养殖需求.一头秦川牛,从犊牛到出栏,需两年以上时间,纯利润有1 000元左右,而黄牛奶改可成倍提高养牛经济效益.富平县宫里镇董村的"三元”改良牛,每年纯利润可达3 000～5 000元,是秦川牛的3～6倍.农村实行联产承包责任制后,为了解决秦川牛养殖效益低,长年吃闲饭的问题,1987年董村请来全国著名养牛专家邱怀教授,进行实地考察指导;又在县畜牧站的领导下,建立了黄牛改良站,用丹麦红牛对秦川牛杂交进行改良,使秦川牛的后代变为奶、肉、役兼用牛.     

秦川牛引入外血杂交改良效果研究(第一报)——短秦F_1公牛生长发育及其屠宰试验

为了探索秦川牛的发展方向,在保留其优良特性的前提下,改进其体型外貌方面的主要缺点,提高其乳、肉生产能力和商品生产率,特引用乳肉兼用型短角牛进行改良,其产肉性能的改良效果通过屠宰试验进行测定。材料和方法 1.试牛选自周至县楼观台牛场1983年8月至11月出生的短秦F_1代公牛6头,同时选同期出生的秦川牛3头作为对照。     

西门塔尔等牛杂交改良蒙城牛的效果调查

<正> 蒙城县位于安徽的北部,内有涡河横穿,气侯温和,土地肥沃,人均耕地2.5亩,农作物以小麦、玉米、红芋为主,具有丰富的饲料来源,对发展以养牛为主的草食家畜有着重要的促进作用。该地牛属华北型,耐粗饲,抗寒抗病力强,适役用,但体型小,力弱,生长发育缓慢,对养牛业的发展有直接的影响。为了改变这种状况,从1980年起,先后引进秦川牛、南阳牛、西门塔尔等牛杂交改良本地牛,促进了养牛业的发展。到1988年底,全县黄牛存栏293097头,户均1.61头,位于全省首位,出栏商品牛70000头,出栏率为26.4％。为了对改良的效果有所了解,确定以后的改良方向,对西本F_1、秦本F_1及本地牛进行了抽样调查,结果如下。     

安秦杂交一代与秦川牛育肥对比试验

2003年9月在陕西省永寿县选择30头18月龄红安格斯×秦川牛和15头18月龄秦川牛进行饲养肥育试验,30头杂交牛分为两组,试验组2在试验组1牛日粮的基础上添加0.2%的发酵剂,15头秦川牛作为对照组,从日增重、健康状况、饲料转化率、投入产出比几个方面进行了比较,试验结果发现:平均日增重,试验组1比对照组提高17.9%,试验组2比对照组提高33.9%;健康状况,试验组2明显优于对照组、试验组1;饲料转化率,试验组1、试验组2比对照组分别提高14.8%和16%。     

秦川牛改良山地牛效果研究

一、历史与现状 1982年我县共养牛13369头,其中山地牛13158头,占牛群总数的96.26％;秦川牛仅473头,占3.46％;其它如肉奶兼用牛、秦巴牛共占0.28％。几年来,在省、市有关部门的关怀、扶持下,给我县先后发放了170万元的黄牛贷款,并引进秦川种公牛37头,加上民桩,全县共有种公牛69头。另外,又先后在县站、     

秦川牛与淮北黄牛杂交效果调查

自1983年以来,我们大批引进了秦川良种牛与淮北黄牛进行了杂交改良。为了解改良效果,我们对杂交牛(以下简称秦淮F_1)的生长发育和生产性能进行了调查。本次调查分初生、6月龄、12月龄、18月龄、24月龄和36月龄6个档次共802头。其中秦淮F_1408头,淮北黄牛394头。同时,我们又对22月龄60天短期育肥的秦淮F_1、淮北黄牛各8头进行了屠宰测定,对秦淮F_1、淮北黄牛各4头进行了役用性能测定。现将调查结果报告于后。     

扶持社员承包养牛 建立秦川牛繁群育

陕西省渭南市为了在新形势下,选育、提高秦川牛,保住这个优良品种。在秦川牛主要产区建立母牛繁育核心群。从1982年8月至1983年6月由市财政部门先后投资3.4万元,建立社员养牛承包饲养户35户,选购秦川繁殖母牛38头;其中特级10头,一级21     

西门塔尔牛、南德温牛杂交改良秦川牛效果研究

[目的]为研究西门塔尔牛、南德温牛对秦川牛的杂交改良效果.[方法]对秦川牛、南德温牛与秦川牛杂交一代（南秦F1）、西门塔尔牛与秦川牛杂交一代（西秦F1）共282头母牛的体高、十字部高、体斜长、胸围、腹围、管围等6项体尺指标进行了测定.以体尺指标为基础材料,对比分析了它们的体重与体尺数据在不同月龄的表现特点;计算分析了它们的各项体尺指数;构建了1～2岁秦川牛各项体尺指标对体重的主成分回归模型.[结果]表明：西秦F1比南秦F1的杂交改良效果好,6～24月龄的秦川牛、南秦F1、西秦F1随着月龄的增加,胸围和体重快速增长,西秦F1的各项体尺指标总体上高于南秦F1与秦川牛,秦川牛与南秦F1差异不显著（P＞0.05）;从育肥指数上来看,24月龄的西秦F1比秦川牛平均高7.2％,差异显著（P＜0.05）,西秦F1比南秦F1高6.8％,差异显著（P＜0.05）,南秦F1与秦川牛差异不显著（P＞0.05）,西秦F1育肥效果优于南秦F1.[结论]对1～2岁秦川牛通过逐步回归得到了估测体重的多元线性回归方程,拟合度较好.     

我县“秦川牛引入兼用短角牛血液中间试验研究”初报

一基本情况为了改良秦川牛在后躯发育(尖斜尻)和股部肌肉欠充实等体形外貌方面的主要缺点,提高其的生产性能、商品率、经济效益和社会效益,1987年秋,西北农业大学畜牧系依据农业部属下达课题,拟定在县故郡乡独山村,协助故郡兽医站进行“秦川牛引入兼用短角牛血液中间试验研究”工作。这项课题的具体步骤是:先以短角公牛为父本配秦川母牛,计划繁殖短秦一代牛1OO头,予产母犊50头左右;再以秦川公牛为父本回交配短秦一代牛,最后在杂种二代公母牛间横交固定,使秦川牛含1/4短角牛血液。这样,     

安哥拉山羊改良建昌黑山羊生产马海毛横交方案的研究

以安哥拉山羊、建昌黑山羊、一代羊(F1)、二代羊(F2)、三代羊(F3)、二代与三代同质个体横交后代(H)为供试羊只,采用形态遗传标记、生化遗传标记和分子遗传标记确定安哥拉山羊改良建昌黑山羊生产马海毛的横交方案。结果:F2、F3 和H白色毛被分别为93 5%、100%和100%,毛被同质和基本同质个体分别为27 7%、70 2%和65 3%;成年羊产毛量随代数增加而增加,但F3 和H与F2,H 与F3 公、母羊分别对应比较,差异均不显著(P>0 05)。成年羊体重F1 和F2 增加,杂种优势明显,但F3 母羊则不显著(P>0 05),H还有下降(P>0 05)。平均基因杂合度和一致度安哥拉山羊、建昌黑山羊、F3、H分别为0 113 1 和0 886 9, 0 062 1 和0 937 9, 0 110 3 和0 889 7, 0 110 4和0 889 6。安哥拉山羊与F3 和H的遗传距离小,分别为0 003 9和0 004 0,遗传相似系数大,相应为0 996 1、0 996 0。群体内谱带相似系数,安哥拉山羊、F2、F3 和H分别为0 454 0,0 407 6,0 611 3 和0 610 9。且F3 和H均极显著大于安哥拉山羊(P<0 01)。综合研究表明,可在F2 和F3 代中选择理想同质个体进行横交。     

陇县不同地区饲养管理条件下黑黄母牛泌乳性能对比分析

陇县川塬区奶改牛饲养条件较好，符合饲养标准，而浅山区的牛只饲养较差，日粮产奶净能比标准低，１．８７兆卡，可消化粗蛋白质少２２７．５ｇ。黑黄１代（第３胎次）平均挤奶天数川塬区的比浅山区的长１６．２％，产奶量高出４３．６％，里黄２代（第２胎次）则分别高出６．０％和１８．９％，为更好发挥奶改牛的产奶潜力，有必要迅速提高农民的科学养牛水平，增加基础投入。     

世界及我国奶山羊产业发展现状及趋势分析

近年来,世界山羊养殖数量持续增长,据联合国粮农组织(FAO)统计显示,2018年全球山羊养殖数量已超10.4亿只,其中奶山羊养殖数量超2.16亿只,约有90%以上的奶山羊和山羊奶产自亚洲和非洲。欧洲的奶山羊存栏和产奶量均在亚洲和非洲之后,但其单产水平远高于其他各大洲,在世界奶山羊每只平均年产奶量100 kg以上的国家中,前十位均为欧洲国家。我国奶山羊产业发展迅速,2018年我国奶山羊实际存栏约518万只,年产羊奶量约100万t,约占全国鲜奶产量的3.3%。本文对全球及我国奶山羊产业进行了纵向和横向比较,客观分析我国奶山羊产业的地位、发展现状以及未来发展趋势,旨在为我国奶山羊产业的发展提供参考。     

草原红牛导入丹麦红牛血液试验效果(第二报)

为了提高草原红牛的生产性能,1985年开始在翁牛特旗海金山种牛场进行了草原红牛导入丹麦红牛血液试验。初步试验结果表明:丹红F_1毛色基本同草原红牛;尻部宽、长而平,原有斜尻缺点已明显得到改进;各阶段体重、体尺均有明显提高,尤以体躯的重量、宽度、高度和后躯的提高更为显著;适应性与草原红牛无差别;其产肉性能和产奶性能比草原红牛亦有明显提高。     

Prevalence of subclinical udder infections and individual somatic cell counts in three dairy goat herds during a full lactation

For dairy goats, both the determination of the somatic cell counts (SCC) and the interpretation of these values may be a problem. Several investigations have shown that SCC for goat's milk, even from not infected mammary halves, are often higher than for cows milk. In the three herds examined about 40% of mammary halves and 30% of the goats were infected. However large differences between the three herds could be observed. In most cases, infections were caused by coagulase negative staphylococci (CNS) or corynebacteria. The SCC of individual milk samples from goats without any udder infection hardly differed from those of goats with at least one udder half infected with CNS. In 20% and 30% of the cases the SCC was higher than 750'000 cells/ml, respectively. The relation between California Mastitis Test (CMT) reactions and udder infections was not very close. Over 20% of mammary halves infected with CNS showed negative CMT reactions. On the other hand, 25% of samples from mammary halves without a proven infection reacted positively. The large differences in individual cell counts on herd and animal level indicate that production and breeding systems might be important reasons for the higher SCC. As a consequence, the most common methods for or the control of udder health and udder infections (SCC, California Mastitis Test) are of limited value for goats. Since there was only a weak relation between milk quality properties and SCC, any arguments for the introduction of legal limits below 1 million cells per ml can hardly be found.     

Manipulation of milk production and quality by use of somatotropin in dairy ruminants other than cow.

The ability of recombinant bovine somatotropin (BST) to enhance milk production is well established in cows and in other dairy ruminants. In dairy ewes, we found increased milk yield (20-30%) following treatment with BST, which did not negatively affect the gross composition or coagulating properties of milk, except in the advanced stage of lactation, when the percentages of milk protein and fat were reduced and the coagulation time was improved (shorter) compared with untreated animals. In dairy goats, administration of BST increased overall milk yield by 14-29%. Our studies and those of others on the Italian river buffalo showed that BST treatment increased milk yield by about 17%, or more, when associated with dietary protected fat, without affecting milk protein content. In general, studies on dairy ruminants show that treatment with BST increases milk production in the short term (immediate postinjection period) and that there is also a medium to long term effect on persistency of lactation. There is evidence that mammary gland involution can be at least partially reversed by BST administration, and this could be due to limitation in the decrease in mammary parenchyma as lactation progresses and/or to modulation of the plasmin-plasminogen system.     

布尔山羊与福清山羊杂交改良效果

对选育的波福杂 1代 6 0只 (公羔 30、母羔 30 )和当地福清山羊 6 0只 (公羔 30、母羔30 )分别进行生理指标和生长发育测定。结果显示 :波福杂一代生理常数与福清山羊相一致 ,表现出较强的适应性 ;杂交一代山羊具有较显著的杂种优势 ,0～ 4月龄、6月龄、8月龄时体重分别比福清山羊分别高 0 .38、1.0 1、2 .10、2 .97、2 .93、4 .32和 6 .12kg ,经t检验各月龄体重、体高均差异显著(P <0 .0 5 ) ,6、8月龄时表现体长测值差异显著 (P <0 .0 5 ) ;饲养管理较好的波福杂交 1代在体形和生长发育速度上接近布尔山羊 ,显示布尔山羊显著的父系遗传优势。     

Effects of herbage intake on goat performance in the mediterranean type natural pastures

This study aimed at identifying changes in natural pastures during the grazing season and investigating the effects of these changes on pasture feeding potential for high yielding dairy goats. During the study, 12 dairy goats were grazed on a 1.5 ha natural pasture for three months from April to June in 2003, 2004 and 2005. The goats were fed 0.5 kg/day of concentrate as a supplement during the grazing season. Botanical composition, herbage production and intake, crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents of the pasture were determined. Live weight, milk yield, milk dry matter (DM) and fat content of the goats were monitored. The data were analyzed using a linear model, which evaluated the effects of grazing seasons in each year. Based on the three-year average, 87% of pasture was herbaceous plants and the remaining was shrubs in DM basis with Cistus creticus , Quercus ithaburensis , Pistacia atlantica and Asparagus acutifolius being the major shrub species. The herbage yield in June was significantly lower than in other months in all years ( P  = 0.001). In all experimental years, the CP content of the pasture decreased but the structural carbohydrates increased as the grazing season proceeded. While live weight was not affected by grazing periods except for 2004 ( P  = 0.001), milk yield significantly decreased with advancing grazing period ( P  = 0.001). The results of the present study indicate that natural pasture has a supportive effect in April and May on the milk yield of lactating goats which are in mid-lactation, and suggested that supplementary feeding is required in consecutive grazing periods.     

The effect of two levels of dietary protein on resistance and resilience of dairy goats experimentally infected with Trichostrongylus colubriformis: comparison between high and low producers

Numerous studies have examined the interactions between protein nutrition and the response to nematode parasitism in sheep, but very few in goats. Compared with other ruminants, goats are less resistant to nematode infection. In addition, in dairy goats, high producing animals have been shown to be less resistant and less resilient to infection compared to low producing ones. The objective of the present study was to examine the consequences of protein supplementation on both resistance and resilience of dairy goats to nematode trickle infection, taking into account the initial level of milk production of the animals. During a 14-week period, 40 milking goats received a high protein (HP) diet supplying 130% of the protein requirements, and 38 goats were fed a intermediate protein (IP) diet (120% of the protein requirements). In addition, half of each group was given a weekly trickle infection with Trichostrongylus colubriformis larvae, the other part of the flock remained non-infected. Faecal egg counts (FEC), eosinophil counts and pathophysiological data (urea, albumin and inorganic phosphate concentrations in the serum) were measured twice a month. Milk production data (milk yield, protein and fat contents) were also recorded every 15 days. The results showed that FECs were lower (p < 0.05) and eosinophil counts higher (p < 0.05) in the animals receiving the HP diet suggesting that resistance was enhanced by protein supplementation. Meanwhile, milk parameters (related to resilience) were not affected by the level of protein in the diet when considering the whole groups. In contrast, in the high producing goats, the milk production and milk composition parameters were improved with the HP diet. To conclude, we have seen that the expression of both resistance and resilience did not appear when the coverage of the protein requirements was insufficient. Because the milk production is dependent on the protein supply, we suggest that there is a competition in the use of the protein between the development of resistance and the milk production.     

Negative effects of long-term feeding of high-grain diets to lactating goats on milk fat production and composition by regulating gene expression and DNA methylation in the mammary gland

Background: It is well known that feeding a high concentrate(HC) diet to lactating ruminants likely induces subacute ruminal acidosis(SARA) and leads to a decrease in milk fat production. However, the effects of feeding a HC diet for long periods on milk fatty acids composition and the mechanism behind the decline of milk fat still remains poorly understood. The aim of this study was to investigate the impact of feeding a HC diet to lactating dairy goats on milk fat yield and fatty acids composition with an emphasis on the mechanisms underlying the milk fat depression. Seventeen mid-lactating dairy goats were randomly allocated to three groups. The control treatment was fed a low-concentrate diet(35% concentrate, n = 5, LC) and there were two high-concentrate treatments(65% concentrate, HC), one fed a high concentrate diet for a long period(19 wks, n = 7, HL); one fed a high concentrate diet for a short period of time(4 wk, n = 5, HS). Milk fat production and fatty acids profiles were measured. In order to investigate the mechanisms underlying the changes in milk fat production and composition,the gene expression involved in lipid metabolism and DNA methylation in the mammary gland were also analyzed.Results: Milk production was increased by feeding the HC diet in the HS and HL groups compared with the LC diet(P 0.01), while the percentage of milk fat was lower in the HL(P 0.05) but not in the HS group. The total amount of saturated fatty acids(SFA) in the milk was not changed by feeding the HC diet, whereas the levels of unsaturated fatty acids(UFA) and monounsaturated fatty acids(MUFA) were markedly decreased in the HL group compared with the LC group(P 0.05). Among these fatty acids, the concentrations of C15:0(P 0.01), C17:0(P 0.01), C17:1(P 0.01), C18:1 n-9 c(P 0.05), C18:3 n-3 r(P 0.01) and C20:0(P 0.01) were markedly lower in the HL group, and the concentrations of C20:0(P 0.05) and C18:3 n-3 r(P 0.01) were lower in the HS group compared with the LC group. However, the concentrations of C18:2 n-6 c(P 0.05) and C20:4 n-6(P 0.05) in the milk fat were higher in the HS group. Real-time PCR results showed that the m RNA expression of the genes involved in milk fat production in the mammary gland was generally decreased in the HL and HS groups compared with the LC group. Among these genes, ACSL1, ACSS1 2, ACACA, FAS, SCD, FADS2, and SREBP1 were downregulated in the mammary gland of the HL group(P 0.05), and the expressions of ACSS2, ACACA, and FADS2 m RNA were markedly decreased in the HS goats compared with the LC group(P 0.05). In contrast to the gene expression, the level of DNA methylation in the promoter regions of the ACACA and SCD genes was increased in the HL group compared with the LC group(P 0.05). The levels of ACSL1 protein expression and FAS enzyme activity were also decreased in the mammary gland of the HL compared with the LC group(P 0.05).Conclusions: Long-term feeding of a HC diet to lactating goats induced milk fat depression and FAs profile shift with lower MUFAs but higher SFAs. A general down-regulation of the gene expression involved in the milk fat production and a higher DNA methylation in the mammary gland may contribute to the decrease in milk fat production in goats fed a HC diet for long time periods.