滩羔羊生产的最佳羊群结构研究

以增加滩羊肥羔生产为目的,对滩羔羊生产曩佳羊群结构进行了研究。结果表明,在确保羊群有效繁殖能力的同时,基础母羊比例越大,其生产效益越好,在试验中基础母羊比例达到80．9％、公羊5．62％、育成公羊1．12％、育成母羊12．36％,不养羯羊,可得到最佳的经济效益,是适宜肥羔生产的最佳羊群结构。     

牛培信养羊有绝招

吉林省抚松县沿江乡口水滩村养羊户牛培信家，现在羊存栏110只，出栏20只，可繁母羊31只，春季产羔46只，成活45只，成活率为97．8％。牛培信养羊十几年，他懂科学会管理，经济效益非常好。他的经验是：1．讲究质量，在优去劣。牛培信养羊特别讲究种公羊质量，他挑选来的种羊只用一茬，配种结束后，不是调换出去，就是淘汰育肥。而且还注意淘汰老龄母羊和奶量不足的母羊。他的羊群中没有一只畸形羊，羊群质量好。2．科学安排配种产羔季节，羊成活率高。牛培信能科学安排羊的配种产羔，使母羊产羔避开严寒、酷暑，又赶在农闲时节，不与农忙争…     

提高农村养羊户羊群繁殖力的八条措施

１选择高产母羊坚持长期选育可以提高整个羊群的繁殖性能。山羊中一般无角母羊的产羔数高于有角母羊；有肉髯母羊的产羔性能高于无肉髯的母羊；一般初产母羊能产双羔的，除了其本身繁殖力较高外，其后代也具有繁殖力高的遗传基础。据报道：初产单羔的母羊，随后三胎平均每胎产羔数为１．３３只、１．３１只、１．４只，而初产双羔的母羊随后三胎平均每胎产羔数分别为１．７３只、１．７１只、１．８８只，可见应选留初产双羔的母羊继续作种，也可选用双胎公羊与双胎母羊交配的后代母羊作种。２种公羊来自高产母羊的后代俗话说：“公羊好好一…     

高寒草地绵羊优化生产研究

为了探索高寒草地绵羊优化生产的方法，选用２５２只罗新藏杂种羊组成试验羊群在围栏草场定居放牧。羊群结构为：种公羊２．７７％，适龄母羊７１．９４％，后备羊２０．６３％，羯羊６．３５％，年龄结构近似于金字塔。结果表明：幼羊繁活周转率达４６．８３％，羊只总增率达４０．８７％，出栏率为４０．４８％，分别较试验所在地若尔盖县同期养羊生产指标提高１４．３８％、１４．４０％、１６．３０％，效果十分明显。同时为高寒草地绵羊实行定居放牧可行性提供了依据     

48～50支半细毛羊选育与提高研究

国家“九五”重点科技攻关项目“48－50支半细毛羊品种选育与提高”经五年的实施，选育出特一级羊6994只，等级羊5．09万只，基础母羊6．94万只，项目区内羊群规模达13．36万只。成年公羊，成年母羊平均体重分别为88.7kg和54.13kg，剪毛量6.81kg和4.76kg，羊毛长度17.43cm和14.95cm，成年母羊产羔率110．3％－125．7％，净毛率71．8％。     

羊放牧的方法

1放牧羊群的组群 合理组群有利于放牧管理,以及羊的选留和淘汰,并且可以合理利用和保护草场,经济地利用劳动力和设备,充分发挥牧地和羊的生产潜力。放牧羊群应根据羊的数量、品种、性别、年龄、牧地等具体情况合理组群。羊的数量多,同一品种可分为种公羊群、一般公羊群、育成公羊群、羯羊群和育种母羊核心群、成年母羊群、育成母羊群等。在成年母羊群和育成母羊群中,还可鉴定等级组群。羊的数量少,不能多组群时,应将种公羊单独组群,母羊组成繁殖群和淘汰群。非种用公羊应去势,防止劣质公羊在群内杂交乱配,影响羊群质量的提高。羊群大小,要根据羊的质量、生产性能和牧地的地形与牧草生长情况来定。一般种公羊群要小于繁殖群,高产性能的羊群要小于低产性能的羊群。地形复杂、植被不好,不宜大群放牧的地区,羊群要小,反之羊群则大。就地区而言,在牧区放牧羊群的规模,繁殖母羊群一般以250-500只,半农半牧区100-150只,山区50-100只,农区30-50只为宜。育成公羊群可适当增大,核心母羊群可适当减少,成年种公羊20-30只,后备种公羊40-60只为宜。     

防止母羊空怀和流产的六项措施

羊群在饲养放牧过程中,母羊因配种不当和受群羊的冲撞,极易发生空怀和流产。因此,养羊户要想提高经济效益,必须采取以下六项措施: 一、选好种公羊。种公羊品种的优劣,是保证母羊优孕的基础。种公羊的蛋白质营养决定精子的密度和精子的活力。因此,要供给种公羊全价营养,特别是保证种公羊蛋白质和维生素的需要,增加饮水量,以提高公羊的射精量。对性欲不旺的种公羊,也可采用药物治疗,用地龙10克、淫羊藿10克研末灌服疗效良好;精子少或没有精子的公羊要适当增加动物性蛋白饲料。     

寒羊饲养讲座

第二讲 寒羊繁殖 羊的繁殖,包括生殖细胞(精子和卵子)的形成、交配、受精、妊娠、分娩和泌乳过程。通过繁殖,增加数量,提高质量。1 选择好种羊 俗话说“公羊好好一坡,母羊好好一窝”,公羊数量少,是羊群中的精华,担负着对群体品质改进和提高的任务。母羊数量多,是羊群中的基础,“母壮儿肥”,母羊好,其后代也错不了。因     

辽宁绒山羊绒直径变异的研究

本文系统分析了环境因素对辽宁绒山羊绒直径的影响、绒直径的遗传特点及其群体绒直径的分布情况。羊绒自根部至尖部逐渐变粗，尖部与根部绒直径相差３．３１μｍ；体躯绒直径最小部位与最大部位差异为２．０９μｍ；３周岁时绒直径最大，公羊平均绒直径比母羊高１．０μｍ；同一公羊雄性后代的绒直径比雌性后代平均高０．５１μｍ；公羊年龄对后代具有显著的影响（Ｐ＜０．０５）；绒直径的遗传力为０．４２１，与产绒量、体重的遗传相关分别为０．６５８和０．１１２。部分公羊的后代具有产绒量高、体重大而绒直径小的理想组合。在整个群体中２６．４０％的母羊和５３．５１％的公羊生产１４．５μｍ以下的羊绒，９．６％的３周岁母羊和５．９％的３周岁公羊生产１４．５μｍ以下的羊绒     

绵羊的高效繁殖技术

绵羊高效繁殖是实现高效养羊产业化的核心技术，直接影响着养羊生产效益。只有在选种选配等各生产阶段科学、规范地饲养管理绵羊，才能从根本上提高绵羊的繁殖技术，从而促进养羊业的进一步发展。人工授精：通过器械的使用，以人工方式采集公羊精液，对精液品质进行检查和处理，再借助器械把精液输进发情母羊的生殖道内，从而以实现母羊受胎的配种技术。相较于本交而言，人工授精可在最大程度上加大优秀种公羊的利用率，所配母羊数能提高数倍，不仅加快羊群遗传进展，而且能预防疫病播散，最大程度上降低种公羊饲养费用。     

Identification and control of paratuberculosis in a large goat herd

Mycobacterium paratuberculosis infection was detected in 2 goats in 1974 and in 5 goats in 1975; 5 of which were from a single herd. The magnitude of the subsequent epizootic in the goat herd was not recognized until 1977, when results of bacteriologic culture of fecal and tissue specimens, antibody determinations (agar-gel immuno-diffusion test), and histopathologic studies became available. By 1984, paratuberculosis had been diagnosed in 124 goats. Nearly all the goats were being used in antiserum production and had been given Freund complete adjuvant and human antigens. From 1974 to 1986, herd size varied from 100 to 300. The yearly incidence of paratuberculosis decreased from 13.2% (27 of 204 goats) in 1977 to 0% in 108 goats in 1985. The prevalence was higher in does. In goats that arrived on the farm in 1975 and before, 49 of 121 (40.5%) does developed paratuberculosis vs 41 of 120 (34.2%) wethers. In goats arriving on the farm in 1976 and after, 25 of 274 (8.5%) does and 9 of 216 (4.1%) wethers developed paratuberculosis. The average incubation period was approximately 4 years from arrival on the farm in every year except 1978, regardless of whether the goat was born on the farm or was purchased elsewhere.(ABSTRACT TRUNCATED AT 250 WORDS)     

Performance of a Johne's disease enzyme-linked immunosorbent assay adapted for milk samples from goats.

Antibody detection-based tests for paratuberculosis offer speed and economy, 2 diagnostic test attributes important to animal industries with narrow profit margins. Application of such tests to individual milk samples instead of serum samples can further improve testing efficiency and decrease testing cost. Accuracy of a commercial bovine paratuberculosis enzyme-linked immunosorbent assay (ELISA) adapted for use on goat serum and milk samples was determined. Fecal, blood, and milk samples were collected from 159 goats belonging to 2 Wisconsin goat herds with a prior history of paratuberculosis and 1 herd of 50 goats from a paratuberculosis-free Wisconsin herd. Fecal samples were cultured using the modified BACTEC 12B media. Sera were tested according to the manufacturer's instructions for bovine samples. Milk samples were centrifuged and mixed with the ELISA kit's Mycobacterium phlei-containing diluent at a ratio of 1:2. Using fecal culture as the "gold standard," the sensitivity of the ELISA on goat serum was 64% and the sensitivity of the ELISA on goat milk was 48%. The milk ELISA had higher agreement with fecal culture results (kappa = 0.525) than the serum ELISA (kappa = 0.425). ELISA specificity was 100% on both serum and milk. Regression analysis also showed good correlation between serum and milk S/P values (r2 = 0.67). Although less sensitive, the ELISA on goat milk samples appears to offer a useful, low-cost alternative for detection of goats with paratuberculosis that have progressed to the stage of shedding M. paratuberculosis in their feces.     

Effect of culling age of does on milk and meat production in Japanese-Saanen goats

A functional herd dynamics model was developed to estimate the effect of culling age on milk and meat production for Japanese-Saanen goats in relation to changes in prices of milk and meat. The model simulates life cycle production of bucks and does and their kids. Every production trait is first modelled as an individual trait and thereafter as a trait in the herd using a herd dynamics model. At the individual level, the survival curve function, the litter size function and the production traits function are combined. Data on growth and lactation were used to fit growth and lactation curves to estimated parameters using non-linear least squares regression technique and used in the production traits function. Using herd dynamics, the individual level functions are combined with the total number of animals function to estimate the total herd output and income efficiency at the herd level. Here, variables of culling days including the effect of difference in meat price value among goat categories (bucks, does, male kids and female kids) are used. Analysis of interrelations among the culling days of does, the price ratio and the income efficiency indicated that optimal culling days of does was shortened with an increase in the price ratio of meat to milk. However, when meat price value was different among goat categories according to actual situation of Japanese goat production, the optimal culling days of does could be fixed regardless of the change in price ratio and was calculated as 1730 days. This functional herd dynamics model can aid in decision-making regarding culling under several situations especially when there is a wide fluctuation in prices at local markets.     

Infection of two goatherds with Mycoplasma mycoides subsp. capri in Hungary,evidence of a possible faecal excretion

During epidemic outbreaks in two goatherds clinical symptoms and deaths occurred in five (14%) of the 3-week-old goat kids in farm A, and in six (33%) of those in farm B. In the latter farm, three female goats aborted before the clinical symptoms in the kids emerged. Mycoplasma could be isolated from both healthy and sick goat kids and from female goats, which had diseased kids or had aborted. Three goat kids (one from herd A and two from herd B) were sent for post-mortem examination. In all these cases septicaemia caused by Mycoplasma was diagnosed. Based on the bacteriological examination the Mycoplasma strains proved to be Mycoplasma mycoides subsp. capri (Mmc). This was confirmed by the PCR examination. Mmc was isolated from several locations including from the rectum of one healthy female goat, and from two diseased kids. In addition, bacteria were detected in the small intestine in two of the necropsied kids by bacteriological and/or immunohistochemical methods. The finding suggests that Mmc may be transmitted via faeces in goatherds, kept under conventional conditions.     

Toxoplasmosis and iodine deficiency in Angora goats

Toxoplasmosis was diagnosed in two goat herds in the Czech Republic. The 1996 outbreak in the herd of Angora goats was associated with abortions and births of weak kids. No apparent signs of toxoplasmosis were observed in the herd of White Short-Haired (WSH) goats reared under similar conditions. Seroprevalences of 60% and 66% tested by complement fixation and indirect fluorescent antibody tests, respectively, were found in the herd of Angora goats during the outbreak of clinical toxoplasmosis. Significantly lower values were recorded in this herd in years 1994 and 1997 and in the herd of WSH goats between years 1994-1996. Iodine deficiency was also demonstrated in the herd of Angora goats in 1996. Goitre was detected by clinical examination in 39% of animals and mean urinary iodine concentration was 8.0+/-4.65 microg per 11. This concentration rose significantly to 15.7+/-5.02 microg per 11 in the subsequent year. Effects of iodine deficiency on clinical manifestation of toxoplasmosis in Angora goats were discussed.     

Seroprevalence of Mycobacterium avium subspecies paratuberculosis in Korean black goats (Capra hircus aegagrus)

In total, 582 sera from 116 black goat herds were analyzed by a commercially available ELISA kit to monitor the seroprevalence of Mycobacterium avium subspecies paratuberculosis (Mpt) in Korean black goats (Capra hircus aegagrus). The mean number of goats sampled per herd was 5.11, 4.66, and 5.38 for the northern, central, and southern regions of Korea, respectively. The apparent regional prevalence of Mpt was estimated at 18.2-38.2% and 4.6-15.3% for herds and goats, respectively. The Mpt-positive goats were predominantly detected in the south (n=28), compared to either the northern (n=9) or central (n=11) regions (chi=14.459, P<0.05). Our findings indicate that Mpt is prevalent among the goat population, but regional variation exists.     

Serological evidence of lack of contact with caprine herpesvirus type 1 and bluetongue virus in goat population in Poland

Investigation into herd-level seroprevalence of caprine herpesvirus type 1 (CpHV-1) and bluetongue virus (BTV) was conducted in 2007 in Poland. It involved the entire population of goats covered by a milk recording program in 2007, which included 49 goat herds. The number of goats examined in each herd was determined statistically in order to detect the presence of at least one seropositive animal in a herd with a 95% probability and simple random method of sampling was applied. No antibodies to CpHV-1 or BTV were detected. Further calculations were carried out to determine the herd-level true seroprevalence, taking into account sensitivity and specificity of the test as well as several other factors. It can be concluded that till the middle of 2007 population of Polish goats covered by the milk recording program remained negative with respect to CpHV-1 and BTV.     

Risk factors for brucellosis seropositivity of goat herds in the Mexicali Valley of Baja California, Mexico

A case-control study was conducted in the Mexicali Valley to identify risk factors for goat-herd seropositivity for Brucella melitensis. Nineteen case herds (≥2 positive results with the 8% rose bengal plate test (RBT)) and 55 control herds (zero positive results in RBT), matched for herdsize and geographic location, were enrolled. Conditional logistic regression was used to construct a multivariable model of the odds of seropositivity using variables assessed in a questionnaire administered to goat ranchers. The final model for herd seropositivity included increased risk from importation of goats from other Mexican states, the presence of La Mancha breed does, and the presence of does born outside the herd. Increasing herdsize was also highly significant (p<0.01). In addition, a significant (p<0.05) positive association was found between the presence of seropositive dogs (as assessed by RBT) and seropositive goats on the same ranch.     

Prevalence, spread and control of caprine arthritis-encephalitis virus in dairy goat herds in New South Wales

SUMMARY A study of the prevalence, spread and control of caprine arthritis-encephalitis virus (CAEV) in dairy goat herds in New South Wales (NSW) during 1986–1988 found that 56.8% of 1484 goats in 14 dairy herds were infected with CAEV. The prevalence of CAEV infection within most herds not implementing control measures increased during the study. At the end of the study, 59.7% of 1322 goats were infected. The prevalence of CAEV increased with age. Differences between breeds were less apparent. Within seven herds with a high standard of identification of goats, 149 of 812 goats seroconverted in an ELISA. Of these newly infected goats, 142 (95.3%) were > 1 yr of age and 96 (64.4%) were > 2 yr suggesting lateral spread of the virus. Most of the goats > 2 yr of age had been in the milking herd for a minimum of 3 to 6 months. The high seroconversion rate within the milking herd suggested that factors other than the ingestion of infected colostrum and milk before weaning were important for the spread of CAEV. Observations indicated that behaviour of goats, particularly reproductive behaviour among lactating does, and milking herd management practices are important in the spread of CAEV. A high density of livestock, poor livestock control and contamination of feed, water, equipment and personnel were implicated in transmission. Poorly functioning milking machines may also be involved. CAEV was eradicated from 3 herds by the implementation of strict control measures.     

Infection of Two Goatherds with Mycoplasma mycoides Subsp. capri in Hungary,Evidence of a Possible Faecal Excretion

During epidemic outbreaks in two goatherds clinical symptoms and deaths occurred in five (14%) of the 3‐week‐old goat kids in farm A, and in six (33%) of those in farm B. In the latter farm, three female goats aborted before the clinical symptoms in the kids emerged. Mycoplasma could be isolated from both healthy and sick goat kids and from female goats, which had diseased kids or had aborted. Three goat kids (one from herd A and two from herd B) were sent for post‐mortem examination. In all these cases septicaemia caused by Mycoplasma was diagnosed. Based on the bacteriological examination the Mycoplasma strains proved to be Mycoplasma mycoides subsp. capri (Mmc). This was confirmed by the PCR examination. Mmc was isolated from several locations includingfrom the rectum of one healthy female goat, and from two diseased kids. In addition, bacteria were detected in the small intestine in two of the necropsied kids by bacteriological and/or immunohistochemical methods. The finding suggests that Mmc may be transmitted via faeces in goatherds, kept under conventional conditions.