中国瘦肉型猪母本新品系（DVI号系）母猪繁殖性能观察

中国瘦肉型猪母本新品系（ＤＶＩ号系）母猪繁殖性能观察匡继平王海滨王成厚张志强杨德龙李子华刘香成（内蒙古乌海市种猪场·０１６０００）中国瘦肉型猪母本新品系（ＤＶＩ号系）的选育，是国家“七五”、“八五”的攻关课题之一，在选育的性状中提高繁殖性能是其重点。...     

中国瘦肉型猪新品系——DVI号系的乳头性状初探

<正>中国瘦肉型猪新品系——DVI号系的选育,是国家“七五”、“八五”的攻关课题之一,要求母猪多产、仔猪多活、商品猪的载肉量、出栏率高。在这个系统当中,提高繁殖性能是其重点也是难点,随着养猪生产水平的提高,人们越来越意识到繁殖性能的特殊性和重要性,因而,国内外的学者围绕繁殖性能,从配种、妊娠、营养、防病、管理及品种等各个方面,都进行过详细的研究,相比之下,乳头性状对猪繁殖性能的影响却探讨较少,国内外仅有的几篇报道结果也不甚一致,本研究旨在探讨中国瘦肉型猪新品系——DVI号系乳头数的品种特征及与繁殖性能的关系,为育种措施的进一步优化提供依据。 材料与方法     

麦洼牦牛高产奶性能新品系(品种)选育方案

为了保护并有效利用麦洼牦牛这一珍贵的遗传资源,提高麦洼牦牛种质质量,试验针对麦洼牦牛育种现状,制订了适合麦洼牦牛新品系选育的方法,以高产奶性能的麦洼牦牛新品系(品种)选育为目标,研究开放式群体继代选育法的步骤。结果表明:新品系(品种)选育的总体目标、具体目标、选育实施方案、选育方法、选育措施等方面均有所提高。     

两广小花猪(壹号黑猪)新品系选育进展

两广小花猪(壹号黑猪)新品系是以广东小耳花猪、陆川猪两个类群为育种素材,以繁殖性能为主,结合肉质、生长发育及外貌选择,经6年4个世代选育而成的高繁殖力新品系。为分析该品系毛色选育效果及其特性与利用价值,以该品系毛色选育提纯效果及各世代种猪生产性能测定数据为基础进行研究。结果表明,以MC1R基因作为遗传标记基因,结合表型选择,可逐渐纯化新品系群体;总产仔数与产活仔数,3世代初产母猪较0世代初产母猪分别提高1.05、0.72头(P>0.05),3世代经产母猪较0世代经产母猪分别提高0.75、0.76头(P<0.05);生长性状及胴体、肉质性状,3世代未发生较大变化。结论:两广小花猪(壹号黑猪)新品系提纯效果突出,繁殖性能得到明显地改善提高,且未对生长及胴体、肉质性状产生不利影响。该品系的培育为地方猪品种内的品系培育提供参考。     

云南黑山羊新品系生长发育规律的研究

云南黑山羊新品系选育是在引进努比山羊与地方山羊杂交改良的基础上,采用现代动物遗传育种及胚胎移植新技术,经过15年培育的"云南肉用黑山羊新品系群".本试验在舍饲饲养条件下,开展对云南黑山羊品系群生长发育规律的研究,通过对体重、体尺性状测定和分析,掌握生长发育规律,为开展选育、饲养和利用提供基础性数据资料,指导种羊生产.     

猪配套系培育方法之我见

培育配套系首先必须要有一个明确的选育目标和方案。父系要求具有什么特性，母系应该具有什么特性，商品猪应该具有什么特性，都要有比较详细的指标。在培育过程中除非有特殊情况而不得随意改变。选育目标不能太繁杂，但主要生产性状不能忽略，要着重生产性状，一些与生产性状无关的性状不要过于追求，但如有特殊要求者可加之。配套系选育目标不同于单品种选育之处在于其性状指标必须将杂交后的杂交效益考虑在内，     

瘦肉猪新品系DⅣ系及其杂优猪适宜营养水平与饲料配方研究

瘦肉猪新品系ＤⅣ系及其杂优猪适宜营养水平与饲料配方研究华中农业大学畜牧兽医系彭健，熊远著，邓昌彦，范春国中国瘦肉猪新品系ＤⅣ系选育是国家“七五”“八五”重点攻关课题。品系的育种目标除繁殖性能外，还要求瘦肉率和生长肥育性能达到一定水平。研究ＤⅣ系及其杂...     

诸美杜洛克种猪新品系的选育

自2008年组建基础核心群以来,诸美杜洛克种猪新品系的选育采用开放与闭锁相结合的群体继代选育法,经过五个世代选育,各性状都取得了一定的遗传进展,生长肥育性能、胴体性状和体尺选育效果明显,达到并部分超过了瘦肉型种猪的要求,且氟烷基因阴性,肉质优良,符合优质猪肉要求。繁殖性能、日增重等性状还有一定的遗传潜力,需继续加强选育。     

辽宁绒山羊“绒肉兼用型”新品系选育研究

本文系统地阐述了辽宁绒山羊"绒肉兼用型"新品系的选育目标、选育方法和选育结果等,历经9年的群体继代选育,"绒肉兼用型"辽宁绒山羊新品系已经选育到G3世代,并拥有6个家系,核心群基础母羊达3 580只,生产性能得到了较大的提高。     

矮脚黄羽肉鸡新品育出

中国农科院畜牧研究所完成的国家“九五”科技攻关计划项目“矮脚黄羽肉鸡新品系选育及配套研究”,日前获该院科学技术一等奖。该成果应用现代遗传育种理论,将鸡性连锁矮小基因(dw)导入黄羽肉鸡中,采用以鉴定公鸡后裔为主的家系选择法,经过5个以上世代的品系选育,培育出3个各具特点的矮脚黄羽肉鸡专门化品系。筛选出适应不同市场需求的京星黄鸡配套系3个。各新品系和配套系均通过了国家家禽生产性能测定站的测定,达到了优质肉鸡生产的要求。以上新品系和配套系不仅保持了普通黄羽肉鸡的品质和风味,而且繁殖性能和饲料转化效率均有明显提高。…     

Dystocia in beef heifers: A review of genetic and nutritional influences

Breeding beef heifers for the first time at 15 months of age has potential to increase the efficiency of the beef breeding-cow herd. An increased incidence of dystocia in heifers calving at 2 years of age, compared to mature cows, is a major reason many farmers in New Zealand have not adopted the practice. The predominant type of dystocia affecting 2-year-old heifers is feto-maternal disproportion, a condition in which the fetus is too large relative to the size of the heifer's pelvis. Reducing birthweight of the calf is a means of reducing the incidence of dystocia. Birthweight and length of gestation are determined by genotype of the calf, maternal genetic effects and environmental effects.

Bulls with low estimated breeding values for birthweight have been selected for mating heifers; however, the positive genetic correlation between birthweight and mature weight meant that the progeny of these bulls tended to be lighter at finishing, making them less desirable in the beef industry. The genotype of the dam also plays a role in determining the risk of dystocia; the maternal ability of the dam to nurture the fetus influences birth- weight, and the dam's genetic potential for growth influences the size of her pelvic area. Heavy heifers tend to produce high- birthweight calves, counteracting the reduction in the incidence of dystocia resulting from the larger pelvis in larger heifers.

Manipulating feeding level during pregnancy offers an alternative method for manipulating the birthweight of calves. Little is known about the effects of nutrition in early gestation on placental development or birthweight of calves. No differences in the birthweight of calves have been observed in response to variation in feeding in mid-pregnancy, and variable responses in birthweight and the incidence of dystocia to feeding in the third trimester of pregnancy have been reported. Differences in birthweight have not always resulted in differences in the incidence of dystocia, primarily due to differences in liveweight of the heifer also induced by feeding regimens. Variability in the incidence of dystocia in response to feeding level in the third trimester of pregnancy makes it difficult to make recommendations for the feeding of heifers at this stage of gestation. More research is needed into the effects of nutrition in early gestation on fetal and placental development in cattle.     

奶牛发情周期中毛 唾液和乳汁孕酮水平的变化

本实验采用放射免疫分析法(RIA)测定了11头奶牛一个发情周期里毛、唾液、乳汁中孕酮(P_4)含量。经产牛(n=8)的毛和唾液中P_4水平变化与乳汁中P_4水平变化一致。青年牛(n=3)的毛和睡液中的P_4水平变化一致,并分别与经产牛毛和唾液中P_4水平变化一致。7头配种后的经产牛和5头配种后的青年牛分别取20和23天的样品进行妊娠诊断,与配种后60天的直检结果相对照,依据经产牛毛、乳P_4水平进行妊娠诊断的阳性准确率分别是85.7％(6/7)和100％(7/7),依据青年牛毛P_4水平进行妊娠诊断的阳性准确率为100％(5/5)。     

Obituary-Roger Brereton Marshall

Roger Marshall was born in Christchurch on 27 May 1933 and died at his home in Palmerston North on 24 October 2001. He graduated BVSc from the University of Sydney in 1958 and began his professional career in clinical veterinary practice in Morrinsville. Wishing to specialise in veterinary microbiology, he later enrolled in the postgraduate course for the Diploma in Microbiology at the University of Otago under Professor JAR Miles. On gaining the Diploma in 1963, Roger was appointed a foundation lecturer in veterinary microbiology in the newly formed Faculty of Veterinary Science at Massey University.     

玉米赤霉烯酮对后备母猪子宫和卵巢抗氧化和炎症指标及相关基因表达的影响

试验旨在研究玉米赤霉烯酮（zearalenone,ZEA）对后备母猪子宫和卵巢抗氧化和炎症指标及相关基因表达的影响。选择胎次和体重（（23.20±0.68）kg）相近的长×大二元后备母猪48头,随机分为4组,每组设12个重复,每个重复1头母猪。对照组（CON组）饲喂基础饲粮,试验组（T1、T2、T3组）饲喂在基础饲粮中分别添加200、800、1600 μg·kg^-1ZEA的试验饲粮。预试期7 d,正试期40 d。结果如下：1）与CON组相比,T3组血清T-AOC和SOD活性显著降低（P<0.05）,MDA水平显著升高（P<0.05）。2）与CON组相比,子宫组织中,T2和T3组T-AOC活性显著降低（P<0.05）,T3组SOD活性极显著降低（P<0.01）,卵巢组织中,T3组T-AOC活性、T2组GSH-Px和SOD活性显著降低（P<0.05）,T3组MDA水平显著升高（P<0.05）。3）与CON组相比,T2组血清TNF-α和IL-4水平显著升高（P<0.05）,T1~T3组血清IL-10水平显著降低（P<0.05）。4）与CON组相比,子宫组织中,T2组IL-1β水平显著升高（P<0.05）,T1和T3组IL-10水平显著降低（P<0.05）。卵巢组织中,T2组TNF-α水平显著升高（P<0.05）,T1~T3组IL-4水平显著升高（P<0.05）。5）子宫组织中,T3组Cu/Zn-SOD mRNA的相对表达显著低于CON组（P<0.05）,T2组IL-1β mRNA的相对表达显著高于CON组（P<0.05）。6）卵巢组织中,T3组GSH-Px mRNA的相对表达显著低于CON组（P<0.05）,T2组IL-1β mRNA的相对表达显著高于CON组（P<0.05）。综上所述,ZEA能通过抑制SOD和GSH-Px的表达与合成,降低后备母猪子宫和卵巢的抗氧化性能,并引起氧化应激。ZEA能通过促进TNF-α和IL-1β表达与合成引起子宫和卵巢的炎症反应,抑制IL-10的表达与合成从而抑制两组织的抗炎反应。     

Assessment of changes in blood volume in response to resuscitative fluid administration in dogs

Objective: To determine the continuous changes in blood volume in response to fluid administration using an in‐line hematocrit monitor. Design: Prospective study. Setting: Research laboratory. Animals: Four healthy dogs. Interventions: Each dog received intravenous boluses of 80 mL/kg of 0.9% saline (S), 4 mL/kg of 7.5% saline (HS), 20 mL/kg of dextran 70 (D), 20 mL/kg of hetastarch (HES), or no fluids (control, C) on separate occasions. Fluids were administered at 150 mL/min in the S, D, and HES groups, and at 1 mL/kg/min in the HS group. Measurements and main results: Blood volume changes were measured every 20 seconds for 240 minutes using an in‐line hematocrit monitor. There was a rapid rise in blood volume during all infusions. Immediately after the administration of crystalloid fluids, the rapid rise in blood volume ceased. Subsequently, there was a steep decline in blood volume for 10 minutes, and a slower decline thereafter. In contrast, the rise in blood volume continued for at least 10 minutes after the infusion of the colloids was complete, and a plateau was observed for the remainder of the experiment. The blood volume effect, as measured by area under the curve, was significantly greater in the saline group than the other groups during the infusion time and for the 0–240 minutes time period. The areas under the curve for the two colloid solutions were not significantly different from each other during any time periods. The percent increase in blood volume immediately following the infusions was 76.4±10.0 in the S group, 17.1±3.2 in the HS group, 23.0±10.5 in the D group, and 27.2±6.4 in the HES group. At 30 minutes from the start of the infusion, the mean percent increases in blood volumes were 35.2±9.3 in the S group, 12.3±0.9 in the HS group, 35.9±7.3 in the D group, and 36.8±6.5 in the HES group. At 240 h post‐infusion, the mean percent increases in blood volume were 18.0±9.7 in the S group, 2.9±6.1 in the HS group, 25.6±16.1 in the D group, and 26.6±8.6 in the HES group. The C group had a mean percent change in blood volume of ?3.7±3.4 at the end of the experiment. Conclusions: This study indicates that the rapid administration of saline at clinically relevant doses leads to the largest immediate increase in blood volume, although this change is transient because of rapid redistribution of the fluid. Despite a brief increase in blood volume that was almost 3 times the volume administered, hypertonic saline led to the smallest increase in blood volume post‐infusion. The synthetic colloid solutions increased the blood volume by an amount greater than that infused and the effect was sustained for a longer period of time than seen following crystalloid administration, but the maximum increase in blood volume was significantly less than saline. The measurement of continuous changes in blood volume, using an in‐line hematocrit monitor, was a useful means of assessing the dynamic effects of fluid administration in dogs in a research setting.     

Copper deficiency in sheep: An assessment of the relationship between concentrations of copper in serum and plasma

AIM: To assess the relationship between concentrations of copper in serum and plasma in sheep.

METHODS: Concentrations of Cu were measured in paired serum and heparinised plasma samples collected from 110 sheep in nine flocks. Linear regression was used to evaluate whether flock or gender had a significant effect on the association between concentrations of Cu in serum and plasma. The individual results for concentrations of Cu in serum were then compared with those from plasma, using correlation and limits of agreement plotting.

RESULTS: Concentrations of Cu in serum ranged from 7.3 to 22 (mean 14.0) µmol/L, while concentrations in plasma ranged from 9 to 27 (mean 16.3) µmol/L. On average, concentrations of Cu in serum were 2.3 µmol/L lower than in plasma. Over the range of values seen in this study, concentrations of Cu in plasma and serum were significantly correlated (r=0.89), and mean concentrations in serum were 87% of those in plasma. There was no effect of flock or gender on the relationship between concentrations of Cu in serum and plasma. Despite the significant correlation, there was marked variability between individual samples in the proportion of Cu that was lost during clotting, with the 95% limits of agreement for serum Cu ranging from 70 to 104% of the plasma concentration.

CONCLUSIONS: As in cattle, the individual variability in the loss of Cu during clotting in sheep is too great for concentration of Cu in serum to be used as a substitute for that in plasma.

CLINICAL RELEVANCE: When assessing the blood Cu pool as part of the diagnosis of Cu-responsive disease in sheep, the concentration of Cu in plasma should be measured in preference to that of serum. We suggest that a range of 4.5 to 9 µmol/L in plasma be used to define marginal Cu status in sheep.     

Age-Dependent Immunolocalization of Fibronectin and Histological Changes in the Thymus of Rats

Age-dependent variations in the immunolocalization of fibronectin (FN) in the thymus were investigated in 1-, 6-, 12- and 20-month-old male and female Swiss albino rats (Rattus rattus) at the light-microscopic level and the changes with ageing in the histological structure of the thymus were also studied. There were no significant differences in the age-dependent variations in the immunolocalization of fibronectin or in the histological structure of the thymus between male and female rats of the same age but there were increases with ageing in the fibronectin content of the thymic capsule, the connective tissue between the lobules, around blood vessels, and in the medulla and cortex of thymus. The connective-tissue content between lobules, fat cells, Hassall's corpuscles, the thickness of capsule and the ratio of the medulla to the cortex of the lobules showed age-dependent increases in the thymus of rats of both sexes. Decreases in the organ weight/body weight ratio were also observed with ageing.     

不同周龄SPF级SD大鼠胰腺自发性病变的组织学观察

研究不同周龄SPF级SD大鼠胰腺自发性病变的种类及其病变发生率,为药物安全性评价提供背景资料。收集3年安评试验中11、19、31周龄试验对照组大鼠胰腺制作病理切片,光学显微镜下观察SD大鼠胰腺病变的种类及组织形态学特点,并统计其病变发生率。结果显示,大鼠胰腺主要出现了以下病变:①单核细胞浸润:11周龄大鼠该病变的总体发生率为0.6%,其中雌性为0,雄性为1.25%;19周龄大鼠该病变的总体发生率为1.0%,其中雌性为1.0%,雄性为1.0%;31周龄大鼠该病变的总体发生率为1.0%,其中雌性为0,雄性为1.96%。②腺泡细胞空泡变性:11周龄大鼠未观察到该病变的发生;19周龄大鼠该病变的总体发生率为1.0%,其中雌性为0,雄性为2.0%;31周龄大鼠该病变的总体发生率为3%,其中雌性为2.1%,雄性为3.9%。③腺泡细胞萎缩、腺管增生:11周龄大鼠未观察到该病变的发生;19周龄大鼠该病变的总体发生率为0.5%,其中雌性为0,雄性为1.0%;31周龄大鼠该病变的总体发生率为3.0%,其中雌性为1.0%,雄性为4.9%。结果表明,SPF级大鼠胰腺可发生单核细胞浸润、腺泡细胞空泡变性、腺泡细胞萎缩及腺管增生等自发性病变,且病变发生率可随着年龄的增加而增加。     

Variation of gene frequencies in ASIP, MC1R and GREY loci in Thoroughbred horses

The objective of the study has been to verify the hypothesis that the coat colour is regarded in the selection of Polish Thoroughbred horse population. Formally, the colour is not a selection criterion in this breed selected mainly for speed. The material consisted of twelve groups of foals registered in successive volumes of the Stud Book (11,688 foals, in total) and their parents selected to the breeding stud. The frequency of alleles in ASIP, MC1R and GREY loci controlling the coat colours was estimated from the recessive phenotype frequency square in the groups of foals. The inflow of foreign genes was limited and the population great, hence the migration effect was very low. The drift and Wahlund effect hardly influenced the genetic structure in the groups which enabled to analyze the population not divided. The total offspring frequency of recessive a, e and g alleles amounted to 0.1552, 0.4877 and 0.9773, respectively. Accuracy of the assessment of the a and e frequency was confirmed on the basis of test matings. The a, e and g alleles were more frequent in dams than in sires and the a alleles occurred more often in fillies than in colts. The frequency of a and e alleles was higher in the offspring than in the parents. The genotype distribution in the offspring differed from the expected one, assessed from the gamete frequency in sires and in dams. Fewer bay foals were born than anticipated. All the results show that the coat colour is not entirely disregarded in the breeding of Thoroughbred horses. The dominant A and E alleles producing the colour are preferred in the selection, particularly in the sires. This leads to some alterations in the phenotypic structure of the population. On the other hand, the horses are mated randomly, irrespective of the coat colour.     

短花针茅荒漠草地放牧系统微量元素季节变化及盈缺分析

为更有效地防治内蒙古自治区四子王旗地区家畜微量元素代谢病,合理使用微量元素添加剂,采用实地采样和实验室分析相结合的方法,对该地区短花针茅（Stipa breviflora）荒漠草地土壤-牧草-家畜生态系统中微量元素的水平进行检测。结果显示,土壤中铜和硒处于缺乏状态。牧草中铁和锰元素处于过量状态,硒为缺乏状态。与健康绵羊的各项指标相比较,血浆中铁和锰分别于夏秋季节和全年高于正常水平,硒和铜元素分别于秋季和冬季低于正常水平;肝脏中铁和锰全年高于正常水平,铜冬季低于临界值,硒元素秋冬季节低于正常水平;被毛中铁全年高于正常水平,而铜和硒全年低于正常水平。结合放牧绵羊对各种矿物质的进食量和消化率进行综合分析表明,该地区为高铁、高锰、低硒的生态环境,同时铜和锌处于季节性缺乏状态。