气候因素对母牛情期受胎率的影响

为探明气候因素对母牛情期受胎率的影响,笔者依据北镇市气象部门的天气预报,对该地区2004年气候温度和相对气湿做了记录,并对本地区5个乡镇牛人工输精站配种记录进行了调查、统计、分析。结果表明,母牛情期受胎率以气温较温和的5、9月份为最高,而5、9月份的相对湿度值相差较大,分别为44%和67%;夏季6、7、8月气温较高,母牛情期受胎率最低,而相对湿度值差数却较大,分别为59%、78%和74%;气温较低的1、2、3、11、12月份母牛情期受胎率也较低,而这5个月的相对湿度值也不相近,特别3、4月份相对湿度同为38%。但这两个月的母牛情期受胎率分别为78.4%和84.2%。4、10月份平均气温相近,受胎率相近,但月相对湿度分别为38%和54%。由此可见,气温对母牛情期受胎率影响较大,而气湿则无大影响。     

配种季节对奶牛受胎率的影响

选取广州市两家大型奶牛场 1998～ 1999年不同配种季节奶牛情期受胎率的原始数据 ,统计分析当年、当地主要气候因素气温和湿度对奶牛受胎率的影响。结果表明 ,奶牛情期受胎率受气温变化影响较大 ,统计的月气温、平均最高气温、平均最低气温和月内气温超过 3 0℃的天数等指标 ,与情期受胎率呈强的负相关 ,相关性极显著 ;气湿对情期受胎率的影响不大 ,相关系数只有 - 0 .16,相关性较弱。情期受胎率以冬春的 12～ 3月份最高 ,夏秋季的 6～ 9月份最低     

温湿度与母猪受胎率关系的研究

通过对中山市某大型猪场 449头母猪第一情期受胎率的统计及其与温湿度等主要气候生态因子的相关分析表明 ,气温对母猪第一情期受胎率的影响较大 ,它们之间呈极显著的负相关关系。其中月均气温、平均最高气温、平均最低气温及高于 30℃天数与母猪第一情期受胎率的相关系数分别为 - 0 8875 ,- 0 850 7、 - 0 90 84和 - 0 90 5 9,而气湿与情期受胎率的相关系数只有 - 0 2 65 7,经检验相关关系不显著 (P >0 0 5)。高温高湿的气候 ,最易使母猪第一情期受胎率下降。改善养猪的环境 ,夏季要注意防暑或调整日粮或配种时间 ,以提高受胎率     

早期断奶后备母牛繁殖效果研究

选择后备母牛１８头，每组各６头，采用不同的日粮饲喂，进行对照试验，结果试验１组后备母牛初情月龄平均为１０．３个月，第一、二情期受胎率８３．３％，繁殖成活率８３．３％。试验２组后备母牛初情期平均为１１．１个月，第一、二情期受胎率６６．７％，繁殖成活率６６．７％。对照组后备母牛初情期平均为１２．７个月，一、二情期受胎率５０．０％，繁殖成活率５０．０％。     

采取好的防暑对策—可提高奶牛受胎率

玉门地区每年七、八、九月份，气温高达３０．６℃，母牛情期受胎率仅为３０．３％。为探讨暑期提高母牛受胎率的措施与方法，做了如下试验。供试牛：供试牛为本场中国荷斯坦母牛，经检查无子宫、卵巢疾患，发情周期正常，年龄２～６岁健康母牛９０头，随机分试验组、对照I组、对照II组各３０头。试验组与对照组母牛在同一牛舍饲养，牛舍一端墙体装有排风扇，舍内牛位中心线上方装有吊扇。牛舍温度２０～２８℃，相对湿度４５％～６５％。试验组在气温高的中午用凉水喷涮牛体，发情母牛在气温凉爽的早晚进行输精；对照I组的发情母牛在气温…     

浅谈如何提高冬季黄牛冷配受胎率

1996年下半年宁化开始引进法国利木赞细管冻精与本地黄牛进行杂交改良 ,现已冷配黄母牛 5 10 0余头 ,总受胎率达 92 5 %。但由于宁化地处闽西北山区 ,冬季极端最低气温- 9 2℃ ,气候寒冷 ,直接影响冷配受胎率 ,1996年冬情期受胎率仅 38 3%。因此 ,我们组织技术攻关 ,探索冬季受胎率低的原因和提高措施 ,经过 3年的摸索和实践 ,冬季黄牛冷配情期受胎率有了较大的提高 ,1999年冬情期受胎率提高到49 8% ,上升 11 5个百分点 ,现总结如下 ,供同行参考。1　影响冬季黄牛冷配受胎率低的原因(1)冬季是枯草期 ,母牛饲料单一 ,营养不足 ,一般农户饲养…     

母牛各月份发情配种与受胎情况调查

辽宁省昌图县冻配工作已开展多年．冻配技术已普及．我们查看１９９９年配种的记录。统计１０２２头参加配种的母牛、各月份第１情期配种与受胎情况见表１。 将全年分三个阶段．即１～４月份为第１阶段．５～８月为第２阶段．９～１２月为第３阶段。就每个阶段的母牛的配种受胎情况加以分析讨论。 １，第１阶段配种２３２头母牛．第１情期受胎１６６头．受胎率为７１．５％。比全年平均第１情期受胎率高４％。比第２阶段第１情期受胎率高１２％、比第３阶段．第１情期受胎率高３．５％，复配率为２８．４％。 这个阶段属早春时节．母牛正处…     

气温对瘦肉型母猪受胎率影响的研究

根据月平均气温的不同,对海宁市某猪场2014年瘦肉型经产母猪第一情期受胎率进行统计分析,结果表明,月均气温相对较高的6、7、8、9、10月份,其配种受胎率较低,均在80%以下,其中气温最高的7月份,配种受胎率最低为68.2%;月均气温相对较低的1、2和12月份,其配种受胎率较高,均在85%以上,2月份的配种受胎率最高,达90.91%,比最低的7月份高出22.71个百分点。总之,母猪配种受胎率随着环境温度的升高而出现降低。     

奶牛输精后注射黄体酮受胎率高

从1991年1月开始对260头成年母牛和投配的育成母牛在输精后第十天肌肉注射黄体酮60毫克,3月和四月因等待1月和2月所试验牛的妊娠检查结果而没有注射黄体酮,到7月为止的情期受胎率分别为:1月66.6％,2月66.6％,3月40％,4月份35％,5月71.9％,6月77.4％,7月52.1％。使用黄体酮的1—5月平均情期受胎率为66.8％。高温多雨的7     

浅谈如何提高冬季黄牛冷配受胎率

宁化地处闽西北山区,冬季气候寒冷,影响冷配受胎率,1996年冬情期受胎率仅38.3%。经3年摸索,1999年冬情期受胎率提高到49.8%,现小结如下。1　引起冬季黄牛冷配受胎率低的原因　1.1　冬季是枯草期,母牛饲料单一,营养不足,一般农户饲养的母牛只喂给稻草,补充少量的稀粥,缺乏蛋白质、维生素和微量元素,时间一长,牛体掉膘,不仅发情受到影响,也导致排卵机能失调。另外冬季气温较低,昼短夜长光照不足,母牛舍外活动时间少,母牛性机能受到一定的限制。出现母牛发情不正常,或只发情不排卵,或排卵时间延后等现象,失去正常的受胎机会。1.2　冷配点的配种…     

商会自治的基石——商会自治规范研究

在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

猪毛色遗传的研究进展

本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

乳酸杆菌作为益生菌广泛用于人和动物。本文综述了乳酸杆菌改善宿主健康的机制。乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道。文章重点讨论了乳酸杆菌表面成分（表面蛋白、脂磷壁酸和肽聚糖）与肠道受体（Ｃ型凝集素受体、Ｔｏｌｌ样受体和 Ｎｏｄ样受体）,阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制。     

Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF

Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo.     

Mechanism of Action of Probiotic Function of Lactobacilli

乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制.     

Evaluation of serum concentrations of biomarkers of skeletal metabolism and results of radiography as indicators of severity of osteochondrosis in foals

OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis.