欧拉羊种公羊引进甘加地区适应性观测研究

欧拉羊引入甘加境内改良甘加羊中心产区周边的羊只的肉用性能,引入的欧拉羊种公羊行为表现正常,生长发育良好,主要生理生化指标都在正常范围之内.其与甘加羊交配公母比例为1∶38～1∶49,一般在7～9月份配种,12月至翌年2月份甘加母羊产羔,少部分11～12月配种,翌年3～4月份产春羔.甘加羊母羊受胎率在90%以上,羔羊成活率95.7%,无难产.引入的欧拉羊种公羊发病率低于12.5%,死亡率为2%.总之,欧拉羊种公羊引入甘加地区后适应性良好,充分发挥出了种公羊的生产性能,引种获得成功.     

陶赛特种羊引进甘南地区适应性观察报告

陶赛特羊引入甘南州综合实验场后，用以改良当地甘加羊中心产区周边羊只的肉用性能，实验表明引入的陶赛特羊种公羊行为表现正常，生长发育良好，主要生理生化指标都在正常范围之内。其与甘加羊交配比例为1：38—1：53，一般在8～11月份配种，到第二年2—4月份产羔。母羊受胎率93％以上，羔羊成活率89．6％-95％，无难产。这说明陶赛特羊种公羊引入甘加地区后适应性良好，充分发挥出了种公羊的生产性能，引种获得成功。     

贾洛羊杂交改良甘加羊效果观察

引进贾洛羊种公羊杂交改良甘加羊,贾甘F1平均初生重4.05kg、0～6月龄平均日增重132.55g/d,显著高于甘加羊的相应指标,差异极显著(P<0.01)。3、6、18月龄贾甘F1的体重增加明显,差异极显著(P<0.01);体高、体长、胸围、管围均高于甘加羊,杂交优势明显,经济效益显著。     

贾甘F1代与甘加羊生长发育对比研究

通过引进贾洛羊种公羊杂交改良甘加羊,对贾甘F1代与甘加羊生长发育进行对比研究。结果显示:从初生至18月龄贾甘F1代羊生长发育较快,与甘加羊比较体重差异极显著(P<0.01);体高、体长、胸围、管围分别比甘加羊均有显著或极显著地提高。贾甘F1代羊和甘加羊绝对生长在6月龄为最大,达到绝对生长高峰,贾甘F1代羊日增重为162.22g,甘加羊日增重为150.11g。相对生长系数随日龄的增加而下降,体重的生长强度随月龄的增加逐渐减小。     

公羊与母羊为啥不能混养

造成配种时间的错误：公羊与母羊混在一起，就必然会自由交配，可能导致一年四季都有母羊怀孕和产羔。母羊在春季和冬季产羔较好，而冬季产羔又比春季产羔更好。冬季产的羔羊一般是在７～８月怀孕的，那时青草茂盛，母羊膘情好，发情旺盛，排卵多，受胎率高，胎儿发育良好，羔羊断奶时，正赶上天气变暖，能吃上青草，生长发育快，成活率高。因此，平时要把公羊与母羊分开饲养，到７～８月，再选定公羊与母羊交配，这样就可以保证母羊在１２月至翌年１月冬季产羔。配种对象不当：羊一般在７～８月龄就性成熟了，但并不适宜配种，老龄羊及病残…     

冷季舍饲对贾洛羊生产性能的影响研究

针对高寒牧区羊只冷季严重掉膘的问题,以贾洛羊为试验对象进行120 d舍饲试验。结果表明:舍饲条件下经过120 d的饲喂,公、母羔羊的增长率分别为157.72%±41.21%和162.84%±26.85%,显著高于对照组的公羔羊(P0.05);周岁贾洛羊公、母羊掉膘率分别为3.50±2.10%和3.38%±3.37%,极显著低于对照组的公、母羊(P0.01);贾洛羊成年公羊的掉膘率为6.48%±4.40%,极显著低于对照组的公、母羊(P0.01),母羊的掉膘率为8.25%±1.72%,低于对照组的公羊(P0.05),极显著低于对照组的母羊(P0.01);试验组羔羊成活率比对照组提高5.00%,周岁羊死亡率比对照组减少5.00%,成年羊死亡率比对照组减少10.00%。     

掌握好山羊秋季适时配种

在配种的前1～2个月适当增加优质饲料饲草,对种公羊和瘦弱的母羊要补喂一些含蛋白质高的青饲料,因为青饲料的维生素、矿物质含量较高,能增强种公羊的精子活力,促进母羊发情,增加排卵数量.但过高的营养水平也是不适宜的,如公羊过肥则性欲低,母羊过肥则不易受孕.一般在配种前期每只公羊每日补喂混合饲料0．5～1．0kg,鲜草任意采食,骨粉5～10g,鲜鸡蛋2～3枚(直接饲喂)种公羊. 选择繁殖率和生产性能高的公母羊进行繁殖,是提高繁殖率和生产性能的一个重要措施.在生产中一定要重视老羊、弱羊、不孕羊的淘汰工作,保持适龄母羊的比例,以提高基础母羊…     

绵羊的采精及人工授精技术

1种公羊的饲养及调教配种旺季一般给每只种公羊每天补饲1～1.5kg混合精料,其配方为玉米40%、大豆(炒熟)20%、豆饼15%、麸皮24%、骨粉0.5%、食盐0.5%。采精次数多时可加2个鸡蛋,青干草自由采食,冬季补饲胡萝卜。同时加强运动,运动量掌握在每天2h左右,以羊皮肤发热而不致喘气为宜。配种淡季应在保证公羊具有良好的种用体况的前提下,逐步减少精料喂量,防止过度肥胖。在配种前一个月左右要有计划地调教公羊。将公羊和发情母羊放在同一圈里,把发情母羊的阴道分泌物抹在公羊鼻尖上刺激性欲,早晚各按摩一次睾丸,每次10min左右,其它公羊配种或采精时…     

山羊夏季管理要三抓

1.混养无法选择适宜的配种对象。羊一般7～8月龄就性成熟了,但并不适宜配种,老龄羊及病残羊更不适宜配种。只有1.5～7岁龄的健康羊才适合配种。如果公羊和母羊混养在一起,任其自由交配,那么,老弱病残者、幼小者均会怀孕,将严重影响幼小母羊生长发育,严重影响老弱病残母羊的处理,产出的羔羊也弱不经风,成活率低,即使侥幸生存下来,生长也很缓慢。 2.混养不能充分利用良种公羊。自由交配,免不了无效交配或重复交配。一般一头公羊只能负担15～20头母羊,同时公羊精力消耗太大,会缩短利用年限,造成浪费。为此,应将公羊与母羊分开放牧。在配种期,…     

绒促激素调治波尔公羊性欲下降1例

2003年9月20日，本县新街乡某养羊户1只波尔公羊，近2岁。主诉：4-6月份该公羊配种一直正常，性欲很强，到7月份时无性欲，母羊发情时无任何性欲反应。检查，公羊体况良好，精神、食欲均正常，两侧睾丸发育良好。     

Evaluation of Dorset, Finnsheep, Romanov, Texel, and Montadale breeds of sheep: I. Effects of ram breed on productivity of ewes of two crossbred populations

Effects of Dorset, Finnsheep, Romanov, Texel, and Montadale breeds for performance as sires were estimated in the initial phase of a comprehensive evaluation of these breeds as contributors to sheep crossbreeding systems. Objectives were to evaluate the effects of ram breed, ewe breed, season of mating, and two-way interactions. Rams from the five breeds were single-sire-mated with ewes from two breed types to produce lambs over a 3-yr period. Ewes were assigned to one of three distinct 35-d mating seasons initiated each year in August, October, and December. A different sample of six rams per breed was used each year across all three seasons, and each ram was penned with ewes of both breeds. Traits evaluated and number of ewe records were conception rate and litter weaning weight per ewe exposed (n = 3,261) and number born, litter birth weight, average birth weight, number weaned, and litter weaning weight per ewe lambing (n = 2,751). Ram breed and ewe breed interacted (P < .01) for conception rate and litter weaning weight per ewe exposed, implicating mating preferences, particularly of Romanov rams. In mixed groups of ewes exposed to Romanov rams, conception rate was 12.7% lower and litter weight weaned was 8.4 kg lower in the ewe breed presumably less preferred for mating by the rams. On a per ewe exposed basis, Romanov-sired litters produced either the largest or the smallest values for litter weaning weight, depending on the breed of ewe. Effects of ram breed on number born and litter birth weight interacted (P < .05) with season of mating. The largest litters within each ram breed were associated with the October mating season. Montadale and Romanov rams sired larger and heavier litters from August matings than from December matings, whereas the opposite was true for Dorset-sired litters. Texel- and Finnsheep-sired litters were similar in size and weight from August and December matings. Breed of ram differences affected per ewe lambing productivity measurements (P < .01). Differences between ram breeds for ewe productivity were noted, with increased number born and improved survival of crossbred progeny to weaning for Romanov-sired litters. These results may have implications for using these ram breeds as sires in different crossbreeding systems. Structured mating systems or the creation of new composite populations involving these breeds could be used to match the resources, environment, and market of specific production situations.     

Breeding practices,growth, and carcass potential of fat-tailed Washera sheep breed in Ethiopia

On-farm survey of farmers' breeding practices, breeding objectives, and selection criteria and on-station feedlot performance evaluation of Washera sheep were undertaken in Ethiopia. The survey revealed that most (79.8%) of the farmers had no breeding ram. The mating system was predominantly uncontrolled. A majority (75.5%) of the sheep owners reported that they herded their sheep flock by mixing with other livestock species mainly with cattle. During grazing, 44.6% of the farmers mix their sheep flock with neighboring sheep flocks. The major sheep production objective was to generate income from the sale of live sheep. Fast growth, appearance, coat color, and pedigree performance were important ram selection criteria, respectively. Ability to breed at early age, pedigree information, mothering ability, and lambing interval were important selection criteria for ewe, respectively. The on-station performance study involved evaluation of feedlot gains and carcass production under five levels of feeding regimes (300, 400, 500, 600, and 700 g day⁻¹ of concentrate feed) for a period of 93 days. The results indicated that the feedlot growth and carcass performance of Washera sheep were very high, with average daily weight gains of up to 126 g and carcass weight of 16 kg, with the optimal level of supplementation for Washera sheep being at 500 g of concentrate per day for a period of 93 days.     

不同类型藏羊消化率与采食量的比较研究

采食量是放牧家畜生产性能的重要影响因素,在草地生态系统中起重要作用。夏季在甘南夏河分别选取不同生理类群(羔羊、1岁母羊、2岁母羊、3岁母羊、4岁母羊、羯羊和种公羊)的欧拉型、甘加型和乔科型藏羊各4只进行试验。采用二氧化钛指示剂法与粪氮指数法分别测定藏羊排粪量和牧草有机物质消化率,从而计算放牧采食量,并对特征间的相关性进行研究。结果表明:欧拉型、乔科型和甘加型藏羊的平均放牧采食量分别为1031.93、834.59和956.15 g·d^-1,乔科型藏羊放牧采食量显著(P<0.05)小于欧拉型和甘加型藏羊。3个类型藏羊的每kg代谢体重采食量和干物质采食量占体重比差异均不显著(P>0.05)。欧拉型、乔科型和甘加型藏羊对夏河天然草地牧草的平均有机物质消化率分别为50.79%、47.22%和55.58%。欧拉型、乔科型和甘加型藏羊的平均排粪量分别为561.26、484.06和466.74 g·d^-1,其中欧拉型藏羊的排粪量显著高于其他两个类型。试验在高寒地区天然草地研究不同类型藏羊的排粪量、有机物质消化率和放牧采食量,旨在为该地区放牧藏羊的科学饲养与管理提供理论依据。     

甘南欧拉型藏羊杂交改良半农半牧区绵羊试验研究

欧拉羊与半农半牧区绵羊杂交,流产率和羔羊死亡率分别比临潭本地羊本交低10.69%和10.83%,受胎率和繁殖成活率分别比临潭本地羊本交高3.70%和18.53%,繁殖效果良好。欧临F1羔羊初生、一月龄、三月龄、六月龄体重分别比临潭本地羊提高18.24%、24.12%、20.61%、18.60%,说明用欧拉羊改良临潭本地绵羊杂交后代生长发育快,杂交优势明显。     

浅析青海省小尾寒羊的发展现状与方向

通过对青海省引进、纯繁、推广小尾寒羊的情况调查，适应性观察，以及杂交试验分析表明，从山东梁山、郓城等地引进的小尾寒羊在舍饲，羊舍饲条件下，能够适应青海省海拔较低的农区环境，较好的保持了原产地小尾寒羊的品种特性，产羔率220％，羔羊成活率85．67％。生长发育快，体格高大。小尾寒羊不是一个肉用品种，它的品种特性在于生长发育快、早熟、常年发情和多胎性，利用这一优势的有效途径是经济杂交。以小尾寒羊或其杂种一、二代羊为母本，选用良种肉用公羊进行杂交，建立高效、集约化的肉羊生产体系，生产优质羊肉是青海省小尾寒羊养殖的发展方向。     

简阳大耳羊种公羊引入喀斯特高寒山区适应性研究

将简阳大耳羊种公羊引入喀斯特高寒山区,与贵州黑山羊进行杂交,以改良贵州黑山羊中心产区的肉用性能。试验对引入的简阳大耳羊种公羊进行了适应性研究,主要包括行为学观察、生产性能与生理指标的测定、抗病能力观察以及繁殖性能测定。结果表明:①行为学研究得出,放牧条件下简阳大耳羊种公羊反刍时间长于贵州黑山羊;②在引入初期,部分简阳大耳羊种公羊出现了咳嗽症状,经治疗后均痊愈,发病率低于8%,无死亡发生;③简阳大耳羊种公羊在引入2个月后体质量增加最显著,平均体质量增加约11 kg,引入1年后简阳大耳羊种公羊平均体质量增加16.69 kg,为引入时的133.01%,高于贵州黑山羊的增长速度;④引入的简阳大耳羊种公羊主要生理指标正常,与原产地的生理指标基本相符;⑤简阳大耳羊种公羊与贵州黑山羊交配公母比例为（1∶35）^1∶40,受胎率在97%以上,羔羊成活率为92.5%,未出现难产。该试验得出,简阳大耳羊种公羊可以作为喀斯特高寒山区发展养羊业的优良杂交父本进行推广。     

Ram mating behavior after long-term selection for reproductive rate in Rambouillet ewes

Mating behavior is known to be heritable in several species, but it is not known if selection schemes for ewe reproductive traits affect mating behavior of rams. Therefore, our objectives were to determine if divergent (high vs low index) selection of a female reproductive trait (lambs born divided by age of ewe minus one) affects mating behavior patterns of male offspring during training to service an artificial vagina (AV) in a less than natural setting (Exp. 1) or during serving capacity tests (SCT) in simulated natural mating conditions (Exp. 2). The method for evaluating male mating behavior was a series of serving capacity tests to estimate sexual performance. For Exp. 1, five, 30-min observations were conducted to assess the mating behavior of 29 rams (22 mo old) being trained to service an AV. In Exp. 1, percentages of rams mounting (73 vs 36%) and ejaculating (67 vs 29%) differed (P < 0.05) between rams from high and low Rambouillet ewe selection lines, respectively. In Exp. 2, ram classification consisted of exposing each 22- to 24-mo-old ram (n = 48) to three unrestrained ewes in estrus for 18, 30-min tests. Any ram that had not mounted or ejaculated during SCT was evaluated for sexual orientation in a 30-min preference test in which each ram had access to both restrained estrual ewes and restrained rams. In Exp. 2, there was no difference (P > 0.2) in percentages of rams mounting (92 vs 78%) and ejaculating (88 vs 74%) between rams from high and low Rambouillet ewe selection lines, respectively. There was no difference (P > 0.33) between high and low ewe selection line rams for mounts or ejaculations for 18 SCT. Only one male-oriented ram was identified, which was from the high line. In Exp. 2, six SCT were necessary to obtain 95% reliability in sexual performance scores. Results of these studies indicate that long-term selection of ewes for litter size did not alter ram sexual performance after SCT under simulated natural mating conditions or affect incidence of male-oriented rams. Mating behavior observed during training to service an AV was lower for rams from ewes of the low selection line than for rams from ewes of the high selection line. We concluded that long-term selection for reproductive rate in ewes did not alter mating behavior patterns of male offspring; however, test conditions, such as restrained and unrestrained ewes and number of serving capacity tests, may affect conclusions in studies that evaluate sexual performance of rams.     

杜泊羊与巴彦淖尔多胎羊杂交F1代生产性能的研究

旨在研究杜泊羊与巴彦淖尔多胎羊杂交F₁代的生产性能,为新疆库尔勒地区引进巴彦淖尔多胎羊进行肥羔生产和肉羊杂交利用提供依据。试验比较了2017年与2018年同一饲养管理水平下杜泊羊（父本）与巴彦淖尔多胎羊（母本）杂交后代（杜×巴F₁代）和新疆库尔勒地区本地绵羊自然交配所生产的羔羊（对照组羔羊）之间在生长性能、屠宰性能等方面的差异,同时对巴彦淖尔多胎母羊和当地母羊的繁殖性能进行了对比分析。结果表明,2017年与2018年,杜×巴F₁代羔羊的3月龄及6月龄体重极显著（P<0.01）高于对照组羔羊,日增重显著（P<0.05）高于对照组羔羊;除2018年6月龄杜×巴F₁代羔羊体长、胸宽极显著（P<0.01）高于对照组羔羊外,2017年与2018年6月龄屠宰时杜×巴F₁代羔羊的体高、胸深、胸围、管围等体尺指标均显著（P<0.05）高于对照组羔羊;2017年和2018年,杜×巴F₁代羔羊的胴体重分别比对照组羔羊提高了21.07%和22.90%,差异均极显著（P<0.01）;2017年与2018年,杜×巴F₁代羔羊的净肉重、净肉率极显著（P<0.01）大于对照组羔羊;巴彦淖尔多胎母羊的难产率极显著（P<0.01）高于本地绵羊,羔羊成活率极显著（P<0.01）低于本地绵羊,但其受胎率显著（P<0.05）高于本地绵羊,产羔率、双羔率分别比本地绵羊提高了24.72%和3.41倍,差异均极显著（P<0.01）。综合以上结果可以得出,杜×巴F₁代羔羊的生长性能、屠宰性能均优于对照组羔羊,继承了父本杜泊羊优良的生长发育性能;母本巴彦淖尔多胎羊保持了对环境的良好适应性和多胎性。在该地区引入巴彦淖尔多胎母羊,并与杜泊公羊进行杂交,充分利用杜×巴F₁代羔羊的杂种优势,将明显提高该地区肉羊养殖的经济效益。