藏山羊研究

本研究对分布在青藏高原地区的藏山羊，定点进行了系统研究。结果表明，藏山羊盛产山羊绒，西藏那曲成年公羊平均为２５３．０ｇ，母羊为２３３．２ｇ；四川德格相应为１２８．８９和７５．９ｇ。绒纤维物理性能好，两地母羊绒纤维细度分别相应为１６．０２μｍ和１４．１９μｍ，伸直长度为５．２７ｃｍ和５．１０ｃｍ。并且具有板皮品质优良，有一定的产肉性能，暖季抓膘能力强，肉的品质好的特点。我国有藏山羊约１０００万只，具有开发价值。藏山羊Ｔｆ和ＡＫＰ具有多态性，而Ｈｂ、ＡＬｂ、ＬＤＨ、Ａｍ和Ｅｇ未见有多态性。藏山羊平均基因杂合度为０．０９４。藏山羊群体内个体生产性能差异甚大，产乳和繁殖性能较低，尚需加强选育提高。同时，应改善饲养管理条件，提高饲养水平，以发挥其生产潜力。     

提高壤塘藏山羊产绒性能研究报告(续完)

3.4.3绒毛品质 1)绒毛自然长度辽宁绒山羊纯繁的成年羊与原产地比较,绒纤维自然长度公母羊均明显降低(P<0.01)公羊粗毛减短(P<0.01),母羊略有增加(P<0.05).藏山羊绒自然长度比辽宁绒山羊公母分别短2.17 cm和2.32 cm(P<0.01),但达到纺织要求(≥3.5cm).因此提高藏山羊产绒性能还需增加绒长.通过杂交和选种试验,一代绒毛分别比藏山羊公羊长1.38cm和0.47 cm,母羊1.66cm、0.81 cm,效果极显著(P<0.01).详见表4.     

藏西北绒山羊产绒性能研究

对西藏那曲尼玛县、阿里日土县两个原种场的绒山羊绒纤维细度、自然长度、产绒量进行测定.结果表明:两地绒山羊绒产量、细度、长度差异均不显著,绒山羊不同性别绒品质(细度)的指标均优于我国其它绒山羊品种如河西绒山羊、辽宁绒山羊、内蒙古绒山羊.尼玛绒山羊成年公羊、母羊平均绒纤维细度分别为14.00 μm和13.33μm,分别比选育前的平均细度公15.32μm、母16.02μm细1.32μm 和2.69μm;选育后日土县成年绒山羊公、母羊细度分别为13.58μm和13.57μm,平均细度比选育前13.72μm细0.14μm;绒纤维主体细度14μm以下的分别占65.2%和76.19%;绒自然长度4 cm以上的分别占81.56 %和78.87 %;选育前后2县成年山羊平均产绒量分别为188.04 g、180.60 g和278.57 g、279.60 g,个体平均产绒量分别比选育前提高了48.14 %和54.82 %;纯白个体达到95%以上.     

辽宁绒山羊与壤塘藏山羊的杂交效果

应用辽宁绒山羊与壤塘藏山羊杂交 ,结果表明 :辽藏 F1 生长发育快 ,初生、半岁、周岁、成年各阶段体重均显著优于壤塘藏山羊。成年公母羊平均产绒量分别比同龄藏山羊高 2 10 .2 0 g和 16 2 .15 g,即提高 5倍多 ,且绒毛品质优于藏山羊。按 1994年市场价计算 ,饲养一只辽藏 F1 公母羊比饲养一只藏山羊分别增加经济收入 2 0 8.6 3元和 170 .6 1元 ,具有推广价值。     

牙山黑绒山羊产绒性能的研究

为研究牙山黑绒山羊不同年龄的产绒规律,选取240只1~8周岁牙山黑绒山羊母羊,测定放牧条件下绒山羊的产绒性能与绒毛品质。结果表明:在产绒量方面,相邻年龄间牙山黑绒山羊母羊产绒量、绒长度和绒细度均有极显著差异(P0.01);1周岁母羊产绒量最低(379.74 g),2~4周岁母羊产绒量呈逐年增长趋势(475.09~502.63 g),5周岁以后开始下降(466.95 g);在羊绒长度方面,1周岁母羊绒长度最短(5.78 cm),2~4周岁绒长度呈逐渐增长趋势(6.43~6.72 cm),4周岁母羊绒长度最长(6.72 cm),5周岁母羊绒长度开始下降(6.45 cm);在羊绒细度方面,1周岁母羊羊绒细度最小(14.43μm),2~5周岁母羊绒细度呈逐渐增长趋势(15.27~15.86μm),5周岁时达到最粗(15.86μm)。由此可见,牙山黑绒山羊母羊产绒性能和绒毛品质在2~4周岁时达到最佳阶段,5周岁以后产绒性能和绒毛品质开始下降。     

内蒙古白绒山羊及其与藏山羊杂交后代在甘南州的适应性观察

对引进的内蒙古白绒山羊及其与甘南州当地藏山羊杂交的后代(蒙藏山羊后代)在放牧条件下进行了抗寒能力、抗病能力、繁殖性能及生产性能的观察,并对蒙藏山羊后代与甘南当地藏山羊进行对比分析。结果表明:蒙藏山羊后代在生长发育、繁殖性能等指标上,比原产地内蒙古白绒山羊有所降低;蒙藏山羊杂交后代周岁公、母羊的体重、体高、体长及胸围比当地藏山羊分别提高了5.50kg和3.52kg、6.72cm和6.79cm、5.43cm和5.55cm、10.84cm和11.49cm,均差异极显著(P<0.01);蒙藏山羊杂交后代周岁公、母羊的含绒率和产绒量比当地藏山羊后代分别提高了9.32个百分点、9.18个百分点和145.03g、130.23g,杂交改良效果明显。     

陇东优质高产绒山羊选育的研究

通过对陇东绒山羊的选育和提高,组建了陇东优质高产绒山羊群,其成年公母羊产绒量分别为693.75±135.29 g和493.46±93.78 g,和陇东绒山羊新品系公母羊相比,产绒量显著提高（P〈0.05）;公母羊羊绒细度分别为15.03±0.85μm和14.56±0.76μm,和陇东绒山羊相比,差异不显著（P〉0.05）;公母羊羊绒的自然长度分别为5.89±0.63 cm和5.26±0.37cm,和陇东绒山羊相比,差异显著（P〈0.05）。因此,陇东优质高产绒山羊产绒量高,羊绒纤维细、长、延伸性好,属优质山羊绒,符合国际羊绒精纺要求并达到了同类纤维理想水平。     

青海贵德黑藏羊羊毛品质分析

随机选取青海贵德黑藏羊毛样进行了分析。结果表明贵德黑藏羊公、母羊毛辫长度平均分别为26.65cm和24.157cm。羊毛纤维类型的重量百分比,公、母羊粗毛、两型毛、绒毛和干死毛分别平均为46.01%、22.85%、30.74%、0.40%,净绒率为76.77%;毛纤维细度公、母羊粗毛、两型毛、绒毛分别平均为53.88μm、25.43μm、20.45μm。表明,黑藏羊毛具有毛辫长度长,粗毛、绒毛、两型毛比例适中,且干死毛含量少,毛纤维细,净绒率高的特性。     

辽宁绒山羊改良阿克苏本地山羊绒用性能效果研究

辽宁绒山羊与阿克苏本地山羊的级进杂交试验结果表明:随着杂交的级进,成年杂种羊的外貌特征逐代接近于父本,体格变长增粗,毛丛背线分明,毛丛中绒含量逐渐上升,绒用体型明显;抓绒量逐代上升,母羊略强;绒丛自然长度较辽宁绒山羊短,但较阿克苏本地山羊的长,且逐代上升;杂交至F3代,绒的伸直长度较阿克苏本地山羊有明显提高;绒纤维直径均较辽宁绒山羊小,杂交至F3代和阿克苏本地山羊无显著差异,绒细度保持在14μm以下,其它代数也在15.38μm以下。说明杂种羊的产绒量和绒品质在逐渐上升,杂三代绒用性能表现最佳。     

陇东绒山羊专门化品系选育研究报告

选育和提高陇东绒山羊的生产性能,以陇东绒山羊为试验动物,采用数量遗传学和现代繁殖新技术,在甘肃东部地区选育出陇东绒山羊专门化新品系,数量达到18 685只,其中绒长型9 632只,绒细型9 053只。新品系被毛全白,以产绒为主,绒肉兼用,两品系特一级成年公母羊产绒量分别为626.49 g、506.87 g和601.67 g、465.76 g;羊绒细度分别为15.02μm、14.82μm和14.49μm、14.25μm;羊绒伸直长度分别为90.37 mm、75.82 mm和85.41 mm、79.78 mm;春季体重两品系公母羊分别为36 kg和28 kg以上,屠宰率为47.68%,经产母羊产羔率105%。选育结果陇东绒山羊专门化品系外貌特征一致,遗传性能稳定,白色个体稳定在97.6%以上,繁殖性能良好,其中双羔率占约5%。陇东绒山羊专门化新品系具有体质结实,角型整齐,被毛全白,产绒量高,羊绒品质优良,耐粗饲,抗病力强,适应干旱环境条件等优点。     

自贡黑山羊产肉性能研究

对自贡黑山羊4月龄、6月龄、12月龄和成年羊进行了屠宰测定。4月龄羯羊的屠宰率、净肉率分别为47％、34％;6月龄自贡黑山羊公羊、母羊和羯羊的屠宰率、净肉率分别为45．43％、34．17％,47．13％、35．04％,47．60％、35％。12月龄自贡黑山羊公羊、母羊和羯羊的屠宰率、净肉率分别为48.11％、37．53％,47.27％、36．53％,48％、38.47％。成年自贡黑山羊公羊、母羊的屠宰率、净肉率分别为49．4％、38．2％,45.6％、35．9％。比较分析,表明自贡黑山羊早期产肉性能高于国内其它中小型山羊品种。     

福建兔生长模型研究

对693只福建兔黄毛和黑毛2个品系体重进行Logistic曲线模型拟合。结果表明:福建兔黄毛品系公母兔及黑毛品系公母兔的生长模型分别为:y=1(/1/3 679+0.007 1*0.973 1x),y=1(/1/4 197+0.006 6*0.977 8x),y=1/(1/2 830+0.003 2*0.974 3x),y=1(/1/3 290+0.003 5*0.976 7x);2个品系实际生长曲线与Logistic生长模型的拟合度均在0.925以上(P<0.01),其中以福建兔黄毛品系公兔生长模型的拟合度最高(R=0.959);福建兔黄毛品系公兔的生长拐点在120日龄,体重为1 848.2 g,成熟体重为3 696.4 g;福建兔黄毛品系母兔的生长拐点在148日龄,体重为2 099.7 g,成熟体重为4 199.4 g;福建兔黑毛品系公兔的生长拐点在89日龄,体重为1 413.7 g,成熟体重为2 827.4 g;福建兔黑毛品系母兔的生长拐点在104日龄,体重为1 651.8 g,成熟体重为3 303.6 g。     

The interbreeding of sheep and goats.

To determine the outcome of interbreeding sheep and goats, ewes and does were bred to rams and bucks, and their embryos recovered. Pregnancy was monitored in 2 does bred to a ram. Fertilization rates in ram X does, buck X does, ram X ewes, and buck X ewes were 72%, 96%, 90%, and 0%, respectively. Ram X doe fetuses died at 5 to 10 weeks.     

Observations on hand‐mating behaviors,several physiological and hematological parameters in Turkish dairy goats

The aims of this study were to examine hand‐mating behavior of doe and buck and relationships of courtship behavior and physiological and hematological traits according to gestation results. Duration from beginning of observation until mating (M‐C), duration between two copulations (C‐C) and courtship behavioral index value of each sex (CBIVD; courtship behavioral index value of doe, CBIVB; courtship behavioral index value of buck) and mounting behavior of buck, were observed. Experience of doe was affected of CBIVD and CBIVB (P = 0.01 and P = 0.01, respectively). Bucks mounted significantly higher times on experienced does than on inexperienced ones (P = 0.00). On the other hand service number decreased with an increase in M‐C (P = 0.00). Elevated service number was observed with increased mounting frequency of buck (P = 0.03). There were strong correlations between CBIVD and CBIVB (r = 0.48, P = 0.00). Pregnancy was not influenced by vaginal pH value. Does, which gave multiple births, had higher vaginal pH (P = 0.05). Rectal temperature difference of doe had no influence on success of mating and birth type. On the other hand, birth type was affected by rectal temperature difference of buck. There was no significant difference of hematological parameters according to mating results. Hemoglobin, red blood cell count and mean corpuscular hemoglobin concentration values were higher in single births and mean cell volume value was lower in single births.     

Guinea-pig productivity under traditional management

Results of a 12 month study of traditional guinea-pig production in the western highlands of Cameroon are reported. The mean age of guinea-pigs (Cavia porcellus L.) at first parturition, kidding interval and litter size at birth were 126.30±10.40 d, 64.8±1.70 d and 1.63±0.26 kids respectively. The annual reproductive rate was 9.18 kids/breeding doe while the doe post-partum weight was 530 g. Mean body weights at birth, presumed weaning (21 d) and 15 weeks of age were 78.36±3.20, 147.51±8.10 and 418.88±32 g respectively. Type of birth and sex had a significant effect on body weight at all ages. Birth weight dropped significantly from 83.88±2.87 g for singles to 81.57±3.40 g for twins, 74.25±2.39 g for triplets and 73.75±4.12 g for quadruplets. These differences were maintained to maturity (15 weeks). Males were generally heavier than females. Mortality rates were relatively high among kids: 24% at birth, 39% at 3 weeks and 40% at 15 weeks. Productivity indices were 0.827 kg of young weaned per doe per year, 1560 g of young weaned per kg of doe per year and 2.52 kg of young weaned per kg metabolic weight (kg^0.75) of female per year.     

Use of controlled internal drug releasing (CIDR) devices to control reproduction in goats: A review

High reproductive rates are necessary in order to increase the productivity of goat operations. Progesterone and its analogues are widely used in other species to control the reproductive system to facilitate synchronized births, induce fertile estrus or to facilitate the use of assisted reproductive techniques with the goal of increasing productivity of livestock. Progesterone impregnated controlled internal drug releasing (CIDR) devices are approved for delivery of the natural hormone progesterone to synchronize and induce fertile estrus in sheep. A few studies have reported a high estrous response and pregnancy rates when CIDRs are used to induce estrus in goats. However, significant variation exists in the duration of treatment (5‐16 days) and in the use of exogenous gonadotropins as part of the treatment protocol. As gonadotropins are not currently approved for commercial use in small ruminants in the USA, studies are needed to determine the necessity for exogenous gonadotropins and whether they can be replaced by enhancing endogenous secretion through photoperiodic manipulation of the doe and \ or increase stimulation through the ‘buck‐effect’. Future studies must not only evaluate efficacy, but should consider the economic feasibility of using CIDRs in commercial production systems.     

Effect of changing female stimulus on intensive semen collection in young Murciano-granadina male goats

The aim of this research was to study the effect of changing female stimulus on libido and semen characteristics from young Murciano-granadina male goats submitted to intensive semen collection using females not in estrus as teasers. Males were submitted to two different sexual stimulation procedures. In the first procedure, the same doe was used as the female stimulus for three consecutive presentations. In the second, the doe was replaced after the second presentation by a new female. Semen volume, concentration, forward progressive motility, and live spermatozoa were scored. To analyze reaction time (RT), three types of analysis were performed. In the first one, RT was analyzed by multifactor ANOVA, taking as a missing value 300 s when a buck did not ejaculate. In the second, RT also was analyzed by multifactor ANOVA, but data from males that did not ejaculate were removed. In the third, a Cox Survival analysis was carried out by censoring data when a buck did not ejaculate within 5 min of entering the test arena. A decrease in semen volume and sperm concentration in the successive ejaculations was observed, being highly marked in the third ejaculation independent of the stimulation procedure (0.62 vs. 0.38 and 0.43 mL, and 2,828 vs. 2,183 and 2,223 million spermatozoa/mL to the first and third ejaculation respectively; P < 0.05). No significant differences were observed either in forward progressive motility or live sperm rate. Changing the female stimulus in the third presentation had no significant effect on any seminal characteristic. Regarding libido and mounting behavior variables, there was a substantial decrease in RT in the third service when the female was changed (with both types of ANOVA). When censored data were taken into account, the relative risk showed that the probability of a male ejaculating in the third presentation increased almost fourfold when the female was replaced than when the female was the same in all services (P < 0.05). In conclusion, young Murciano-granadina bucks can be used as semen donors because none of the most important semen variables used to reject or accept an ejaculate before freezing process decreased after intensive semen collection. We also recommend changing the female stimulus to make the semen collection procedure more efficient and using survival analysis methodology to analyze time data, mainly when a high rate of censored data are scored.     

Pregnancy detection and the effects of age, body weight, and previous reproductive performance on pregnancy status and weaning rates of farmed fallow deer (Dama dama)

Fallow does (n = 502) of different ages (mature, 2-yr-old, and yearling) were maintained with bucks for a 60-d breeding season to determine whether previous reproductive performance and changes in BW affect doe pregnancy rates and to compare the effectiveness of ultrasonography and serum pregnancy-specific protein B (PSPB) for the detection of pregnancy in fallow does. Ultrasonography was performed, blood samples collected, and BW recorded at buck removal (d 0) and at 30 and 90 d after buck removal. Lactational status (lactating = WET; nonlactating = DRY) were determined from farm records taken at weaning prior to each breeding season (autumn 1990 through autumn 1994). Ultrasonography and PSPB for determining pregnancy were in agreement 93% of the time. Overall pregnancy rates did not differ (P>.10) relative to age of the doe; the combined pregnancy rate was 92%. We also determined that 82.9% of does conceived early in the breeding season and that the incidence of embryonal-fetal mortality during the first 90 d after buck removal was 2.8%. In general, mature and 2-yr-old DRY does were heavier and had lower pregnancy rates than WET does. The overall weaning rate for all does was 77.9%. Loss in the number of fawns from pregnancy detection to weaning was equivalent to 14.8% for mature does, 24.7% for 2 yr old does, and 42.5% for yearling does. These data indicate that even though pregnancy rates were relatively high, further study is needed to determine the causes associated with subsequent fawn losses, particularly among yearling does. As a production tool, lactational WET/ DRY status testing was found to be an acceptable means for determining the reproductive potential of individual does within the herd. In addition, serum PSPB may be used in place of ultrasonography for pregnancy diagnosis in fallow deer as early as d 30 after buck removal.     

Management of Goat Reproduction and Insemination for Genetic Improvement in France

Reproductive seasonality observed in all breeds of goats originating from temperate latitudes and in some breeds from subtropical latitudes can now be controlled by artificial changes in photoperiod. Short days stimulate sexual activity, while long days inhibit it. This knowledge has allowed the development of photoperiodic treatments to control sexual activity in goats, for both the buck and doe. In the French intensive milk production system, goat AI plays an important role to control reproduction and, in conjunction with progeny testing, to improve milk production. Most dairy goats are inseminated out of the breeding season with deep frozen semen, after induction of oestrus and ovulation by hormonal treatments. This protocol provides a kidding rate of approximately 65%. New breeding strategies have been developed, based on the buck effect associated with AI, to reduce the use of hormones. With the development of insemination with frozen semen, a classical selection programme was set up, including planned mating, progeny testing and the diffusion of proved sires by inseminations in herds. Functional traits have become important for efficient breeding schemes in the dairy goat industries. Based on knowledge gained over the past decade, the emphasis in selective breeding has been placed on functional traits related to udder morphology and health. New windows have been opened based on new molecular tools, allowing the detection and mapping of genes of economic importance.