草原红牛乳脂率变化规律的研究

草原红牛的平均乳脂率为３．３５％，随年龄的增长而逐渐下降，由４岁的３．７３％降到９岁的３．１３％；随胎次的增加也逐渐下降，由１胎的４．００％降到６胎的３．１４％；随泌乳月的延长而呈两头高中间低的曲线变化。     

中国草原红牛乳脂率变化规律的研究

单原红牛的平均乳脂率为3.35%,随年龄的增长而逐渐下降,由1岁的3.73%降到9岁的3.13%:随胎次的增加也逐渐下降, 由1胎的4.0%到6胎降到3.14%;随泌乳月的延长而呈两头高中间低的曲线变化。     

高纬度地区毛丝鼠繁殖规律的研究

本文对我国高纬度地区饲养的毛丝鼠进行了繁殖规律观察研究。结果表明，毛线鼠全年都可繁殖，相对集中在３￣１１月份；胎平均产仔１．９２只；年产２胎母鼠占４８．４６％；１￣４岁龄母鼠在繁殖上没有显著差异（Ｐ〉０．０５）；血配母鼠的繁殖率３３．７９％；仔鼠断奶活率９２．３％，育成率８１．３％。     

日粮蛋白水平对生长牦牛血液中若干代谢激素和代谢物的影响

对３头生长阉牦牛在饲喂等能（９．６ＭＪＭＥ／ｋｇＤＭ）不同蛋白水平的日粮时的外周血液若干代谢激素和代谢物浓度进行测定。结果表明，日粮蛋白水平由８％升至１２％后，生长牦牛血清尿素氮浓度增加３９．０％，血糖水平升高６３．５％，血清胰岛素水平升高７６．３％，Ｔ３浓度降低２０．７％，Ｔ４浓度不变，皮质醇浓度则由２．０１μｇ／ｄｌ全部降到检测线以下。     

猪胃肠出血症与饲料

猪饲料粉碎粒度直径由１．１ｍｍ降到０．８ｍｍ消化率提高３％,降到０．４ｍｍ消化率提高７％,人们注意到猪饲料粉碎细了会提高消化率,并可降低断奶仔猪腹泻病的发生。因此生产猪饲料的粉碎粒度逐渐变小。然而在猪饲料直径由１ｍｍ降至０．４ｍｍ时可以显著增加生长肥育猪胃肠的角化程度,胃肠损害程度加剧（Ｗｏｎｄｒａ等,１９９３）,母猪溃疡指数显著增加（Ｈａｎｃｏｄｋ等,１９９３）。玉米的影响大于高粱,对母猪的影响大于生长肥育猪,喂粉料的影响大于颗粒料。当饲料的粒度直径为０．３ｍｍ时,可以观察到明显的角化病和胃肠…     

仔猪睾丸间质细胞增殖和发育的组织学观察

对１￣４周龄仔猪睾丸间质细胞的形态学发育进行了光镜和电镜观察。光交易结果表明：随仔猪年龄增长，间质细胞总数明显增多，到第３周时达到高峰，第４周龄时出现下降趋势，该细胞的密度随其总数的增多而逐渐增加，周围曲精细管逐渐发育成形，至３周龄时与间质组织界限已渐明确，至第４周龄时，部分间质细胞开始退化，而使数量减少。     

系统选育及配套技术对大约克夏猪生产性能的影响

本研究采用配套技术对美系大约克夏猪进行系统选育，取得了良好效果。与选育前相比，除保持了本品种系较高的繁殖性状外，６月龄时日增重由５７４克提高到８２３克，增加２４９克，极显著；料肉比由３．４降到２．５７，降低０．８，差异极显著；瘦肉率达到６５．４％，提高１．６个百分点。     

狐产仔哺乳期的饲养管理技术

银黑狐的产仔期一般在３月下旬至４月下旬，北极狐在４月中旬至６月上旬。此期饲养管理的好坏，会直接影响到母狐的泌乳力和持续时间以及仔狐的成活率。为此，饲养户一定要做好母狐产仔泌乳期的饲养管理工作。１母狐泌乳量与胎产仔关系 母狐每昼夜的泌乳量约占体重的１０％～１５％。如产１０只仔的北极狐，产后１０天内每昼夜平均泌乳量达３６０～３８０ｇ，１１～２０ｄ为４１３～４８４ｇ，到２１～３０ｄ为３４９～３６６ｇ。仔狐对母乳的需要量随日龄增加而提高。但当仔狐开始采食后，对乳的需要量下降，随之母狐的泌乳量也逐渐下降。…     

高效饲料蛋白素代替部分棉仁粕对高温期奶牛产奶量的影响

高效饲料蛋白素由羟甲基尿素和微量元素组成。试验证明，在混合精料中添加１．５％高效饲料蛋白素、４％玉米、３．５％粉麸，以代替９％的棉仁饼，对牛奶产量没有不良的影响，且对因高温引起的产奶量自然下降有一定的稳定和缓冲作用。试验组下降幅度为６．７８％，而对照组为１０．４６％。     

八种因素与牛产奶量密切相关

１品种乳用型牛有黑白花奶牛、荷斯坦、娟姗、瑞士褐牛等。由于牛种和品种的不同，产奶量有很大的差别：少的只有５００～６００kg，多者可达８０００kg，甚至１００００kg以上。要想多产奶，应首选黑白花奶牛和荷斯坦牛。２个体同一品种奶牛的不同个体，由于遗传素质的差异，即使在同样环境条件下，产奶量也不尽相同。不同品种奶牛体型大小也不相同。一般情况下，大体型的奶牛要比小体型的奶牛产奶多。３年龄与胎次产奶量随着奶牛机体的生长发育过程和逐渐衰老而增加或减少。１～２胎（３～４岁）一般要比３胎（５岁）以上低１５％～２０％…     

新疆帕米尔牦牛生产性能的试验研究

[目的]为了探讨新疆帕米尔牦牛的生长发育、繁育性能及泌乳性能等特性。[方法]选取新疆帕米尔母牦牛50 头,通过非配对法人工受孕,检测母牛受配率和受胎率等繁育性能指标,记录产奶量、乳脂指标等评价泌乳性能,并在犊牛初生后分别于第0、1、3、6、12、18及24月龄时测量体重、体尺、体斜长等生长指标。[结果]18月龄新疆帕米尔牦牛的体重达343 kg,显著高于同时期的其他市售牦牛,证明新疆帕米尔牦牛的生长性能良好;繁殖率在75%以上,受胎率在90%以上,发情期集中在8月,繁殖成活率在90%以上,犊牛断奶成活率高达98%,证明新疆帕米尔牦牛具有良好的繁育性能;牛乳的乳脂率和乳蛋白率都达到生乳食品安全国家标准,产奶量也属于同类中的偏上水平,表明新疆帕米尔牦牛具有优良的泌乳性能。[结论]新疆帕米尔牦牛具有生长发育快、生产性能好、经济价值高等优势,是一种乳肉役兼用型的地方优良牦牛品种。     

Production and related variables in bovine leukaemia virus-infected cows

A newly developed milk dot blot test was used to detect anti-bovine leukaemia virus (BLV) antibody in milk samples from 2079 lactating adult cows from among 61 herds. The milk dot blot test was highly repeatable; the concordance rate, compared with the agar gel immunodiffusion test performed on serum, was 83.5%. All herds contained BLV-positive cows; the prevalence rate was 36%. BLV-positive cows tended to come from larger herds and were older and more often later in lactation. Fourteen production and related variables (herd size, age, days open, days in milk, milk somatic cell count, milk, fat, and protein produced in the current lactation, projected production of milk, fat, and protein, and breed class average deviations for milk, fat, and protein) were compared between BLV-positive and BLV-negative cows. Although somatic cell count, milk produced, and projected production of milk and protein were related significantly to BLV status using simple tests of association, once the variables herd size, age and days in milk were controlled, these differences were removed. Further analyses using logistic (outcome: individual cow BLV status) and least-squares regression (outcome:herd proportion of BLV-positive cows) failed to show an association between any of the measured production or related variables and BLV-positivity. We concluded that the effect of BLV on production and related variables in dairy cows was below the sensitivity of our analytical techniques or was non-existent.Abbreviations ABCA herd average breed class average for milk, fat, and protein production - AVGAGE average age of the herd - ADIM herd average for days in milk - AGID agar gel immunodiffusion - AVGSCC herd average milk somatic cell count - BCA breed class average, a milk, fat and protein production index calculated by comparing a cow's actual 305-day lactation production to the corresponding BCA standard for the same breed, age, and month of calving - BLV bovine leukaemia virus - CALVINT calving interval - COWAGE cow age - DBCA breed class average deviation for milk, fat, and protein production, the difference between an individual cow's BCA and the herd average - DIM days in milk - HS herd size corresponding to the number of lactating cows in a herd - LACT actual amount of milk, fat, and protein produced in a cow's lactation - ODHIC Ontario Dairy Herd Improvement Corporation - PCTPOS percentage of herd that is BLV-positive - PROJ projected 305-day production for milk, fat, and protein by fitting to a standard lactation curve adjusted for days in milk and age at calving - RHBCA rolling herd average for breed class average for milk, fat, and protein production, the average for all cows that completed a lactation (cows must have completed a 305-day lactation) during the previous 12 months - SCC milk somatic cell count     

中国荷斯坦奶牛RPL23A、ACACB基因3个SNPs检测及其与产奶性状的关联分析

旨在开展奶牛群体高乳成分功能基因的验证与筛选,利用微流控芯片自主选育技术分析北京地区母牛群体高乳蛋白、高乳脂基因频率,同时分析基因多态性及其与产奶性状的相关性。本研究对北京地区8个大型奶牛场1 596头中国荷斯坦奶牛RPL23A、ACACB基因的多态性进行了检测,所有个体均为3胎以内的泌乳牛,收集每头牛所有测定日的产奶量、乳脂率、乳蛋白率等数据,同时对3个多态位点不同基因型与产奶性状进行了关联分析。RPL23A基因的SNP位点g.20146771G>A,在第一泌乳期,与产奶量、乳脂量、乳脂率和乳蛋白量均达到极显著关联（P<0.01）,第二泌乳期,g.20146771G>A与5个产奶性状均呈极显著关联（P<0.01）。ACACB基因的SNP位点g.63962768C>T,在第一泌乳期,与产奶量、乳脂量、乳脂率和乳蛋白量均呈极显著关联（P<0.01）,在第二泌乳期,与产奶量、乳脂量、乳脂率和乳蛋白率呈极显著关联（P<0.01）。结果表明,RPL23A、ACACB基因可以作为影响中国荷斯坦奶牛产奶性状的候选基因用于标记辅助选择,以上基因位点可能通过直接或间接的途径影响奶牛的乳脂或乳蛋白性状,对产奶性状起到重要调控作用。本研究为荷斯坦奶牛后续的标记辅助选择奠定了良好基础。     

不同能量和蛋白水平日粮对西农萨能奶山羊泌乳性能的影响

为筛选西农萨能奶山羊泌乳期全价料最适能量和蛋白水平,选取体重(50.56±0.76)kg、胎次(2～3)、产奶量(2.12±0.10)kg/d相近和分娩日期与体况一致,并处于泌乳高峰期的健康西农萨能奶山羊36只,随机分为6组,每组6只。采用3×2因子随机区组试验设计6种日粮,NE水平为12.64、13.08和13.52MJ/d,CP水平为16.13%和17.82%。试验期84d,共分4个阶段,每阶段21d。结果表明:日粮NE和CP水平对奶山羊DMI和血液生化指标没有显著影响,但存在交互作用,NE 13.52MJ/d和CP16.13%处理组的DMI最高。随日粮NE和CP水平升高泌乳量增加,其中CP提高可显著增加泌乳量(P=0.041);而乳脂肪、乳蛋白、乳糖、干物质和非脂乳固体等乳成分指标则降低,其中CP提高可显著降低乳蛋白(P=0.013)和非脂乳固体(P=0.031);日粮NE和CP水平对奶山羊泌乳性能的影响存在交互作用,NE 13.52MJ/d和CP17.82%时泌乳量最高,而NE 13.08MJ/d和CP16.13%时乳品质最好。综合各项指标并考虑生产实际,得出西农萨能奶山羊泌乳期日粮适宜的NE和CP水平分别为13.08MJ/d和CP16.13%。     

不同品种泌乳母马不同泌乳月产奶量及乳成分的比较

[目的]研究伊犁马和哈萨克马泌乳母马在不同泌乳月产奶量及乳成分的差异,为开发利用伊犁马和哈萨克马乳用特性提供参考。[方法]随机选择年龄和胎次相近、产驹时间接近、健康的伊犁母马和哈萨克母马各12匹,在日粮营养水平和饲养管理水平相同的条件下,记录2个品种母马在泌乳30、60、90 d的产奶量;采集乳样,测定2个品种母马不同泌乳时间的乳中体细胞数、乳脂率、乳蛋白率、乳糖率和总固形物含量。[结果]泌乳30 d时,哈萨克马的产奶量高于伊犁马（P>0.05）,乳脂率极显著（P<0.01）高于伊犁马,乳中体细胞数显著（P<0.05）高于伊犁马,其他乳成分指标高于伊犁马（P>0.05）。泌乳60 d时,伊犁马的产奶量和乳糖率极显著（P<0.01）高于哈萨克马,乳脂率和乳蛋白率高于哈萨克马（P>0.05）,乳中体细胞数和总固形物含量低于哈萨克马（P>0.05）。泌乳90 d时,伊犁马的产奶量显著（P<0.05）高于哈萨克马,乳糖率、总固形物含量极显著（P<0.01）高于哈萨克马,乳脂率和乳体细胞数极显著（P<0.01）低于哈萨克马,乳蛋白率高于哈萨克马（P>0.05）。[结论]泌乳初期（30 d）,哈萨克马的产奶量和乳营养成分含量高于伊犁马;泌乳中期（60、90 d）,伊犁马的泌乳性能整体优于哈萨克马。在观察期内,哈萨克马的乳体细胞数大于伊犁马。     

西农萨能奶山羊泌乳期产奶量、乳成分及血液生理生化指标变化规律研究

旨在探索西农萨能奶山羊泌乳期生产性能、乳成分、血液生理生化指标和营养物质摄入量等变化规律及其相互关系.本研究选取15只体重、胎次、产奶量、分娩日期相近,体况健康的西农萨能奶山羊.单圈饲喂54周,试验期内准确测定个体生产性能、乳成分、血液生理生化指标和营养物质摄入量等,建立各项指标随泌乳期变化规律模型及泌乳期内指标间的相...     

A Study on the Productivity and Diseases of Camels in Eastern Ethiopia

A study concerning performance traits of the Ethiopian camel indicated that, in the camel herds examined, there was one active bull camel for 25 females. The bull camel was 5 years old at puberty; it reached rutting vigour at the age of 9 years, the number of mountings per day was 8 during the breeding season, and the reproduction span was 10 years. The female camel reached puberty at 4 years of age; the age at first calving was 5 years, and the lactation period was one year; the calving interval was 2 years, the calving rate was 50%, and the reproduction span was 10–15 years. The survival rate of the newborn calves was 50%. The average milk yield was 2.5 L per day; the price of camel's milk was higher than that of cow's milk at US$0.5. Adult camels weighed around 500 kg; the dressing-out percentage was 52%. Mutton was preferred to camel meat, which came second in popularity, costing US$2/kg. Owing to their poor reproductive performance, camels are not efficient for producing meat. The camels worked for 16 h per day, covering 60 km. Animal health problems encountered were trypanosomosis, camel pox, camel pustular dermatitis, camel cephalopsis, dermatomycosis, mange mite, tick infestation and balantidiosis, most of which mainly affected the young animals.     

饲粮全棉籽比例对奶牛泌乳性能及乳脂脂肪酸组成的影响

本试验旨在研究饲粮全棉籽比例对奶牛泌乳性能和乳脂脂肪酸组成的影响.试验采用4×4拉丁方试验设计,选择8头泌乳早期的经产中国荷斯坦奶牛(产奶量、胎次、产犊日期接近,健康无疾病),分为4组,每组2个重复,每个重复1头牛.A组饲喂基础饲粮,B、C和D组分别饲喂含5％、10％、15％全棉籽的试验饲粮.每期试验28 d,其中预试期为7d,正试期为21 d.结果表明:随着饲粮全棉籽比例的增加,奶牛产奶量有提高趋势(P＞0.05),校正乳产量极显著提高(P＜0.01).全棉籽极显著地提高了奶牛的乳脂率(P＜0.01),对乳蛋白率、乳糖率和乳非脂固形物率无显著影响(P＞0.05).全棉籽极显著降低了饱和脂肪酸( SFA)的含量(P＜0.01),不同程度地提高了乳中多不饱和脂肪酸( PUFA)和单不饱和脂肪酸(MUFA)的含量(P＜0.05或P＜0.01);短链脂肪酸和中链脂肪酸含量都显著降低(P＜0.05),长链脂肪酸含量有不同程度的提高(P＜0.05或P＜0.01).结果提示,饲粮中添加全棉籽可以提高奶牛产奶量,优化乳脂脂肪酸组成,改善乳脂品质,并以10％为泌乳早期奶牛最佳饲粮全棉籽比例.     

利用Wood模型拟合中国荷斯坦牛乳脂率变化的效果分析

为了解中国荷斯坦牛乳脂率变化规律,本文利用Wood模型对我国南方5个大中型奶牛场2008~2010年1~3胎中国荷斯坦牛33 194条测定日乳脂率进行曲线拟合。结果表明:中国荷斯坦牛乳脂率变化曲线为典型的倒抛物线形,第一胎拟合度最高(0.9820),第三胎最低(0.9789)。二胎牛乳脂率最先达到最低点(第16周),而三胎乳脂率最后达到(第19周)。就最低乳脂率而言,二胎牛最大(3.54%),而三胎牛最小(3.45%)。综合各方面情况得出,Wood模型适用于中国荷斯坦牛乳脂率变化的曲线拟合。     

Effects of feeding sows fat or fructose during late gestation and lactation

The effects of dietary fat or fructose supplementation during late gestation and lactation on sow milk production and composition and on progeny were examined. On d 88 of gestation, 24 sows were allotted by parity to three dietary treatments (eight sows/treatment). Treatments were 1) a 12.5% crude protein, corn-soybean meal control, 2) the control + 10% added fat or 3) the control + 23% high fructose corn syrup. All treatments were fed to supply 1.82 kg/d of the control diet from d 89 of gestation to parturition with sows in treatments 2 or 3 receiving .18 kg of additional fat or .53 kg of additional high fructose corn syrup, respectively. Feed was gradually increased from d 1 to 7 of lactation to 4.54 kg/d of the control diet (plus .45 kg of added fat and 1.33 kg of added fructose for treatments 2 and 3) and remained at these levels for the remainder of the 21 d lactation period. All treatments were iso-nitrogenous; treatments 2 and 3 were iso-caloric. Litter birth weights, number of pigs born alive, weaning weights and piglet survival rate were not affected by sow treatment. Stillbirths were less (P less than .05) for sows fed fat. Lipid content of milk 24 h post-farrowing was greater (P less than .05) from sows fed fat compared with sows fed fructose. Milk production estimates indicated that multiparous sows fed fat produced more (P less .05) milk than sows fed the control diet. On d 112 of gestation and d 15 of lactation, serial blood samples were drawn to monitor sow response to a glucose challenge (1 g/kg body weight).(ABSTRACT TRUNCATED AT 250 WORDS)