苏云金杆菌δ-内毒素基因(Bt)导入苹果

应用携带改造过的长约１．８ｋｂ抗虫基因Ｂｔ的农杆菌ＬＢＡ４４０４对苹果品种绿袖、金矮生和长富２号的叶片外植体通过真空渗入接种、共培养和在含５０ｍｇ／Ｌ卡那霉素的培养基上筛选７０ｄ,获得对卡那霉素具抗性、存活并产生愈伤组织的外植体为１６．７％￣３７．３％,其中１８．７％￣９２．９％的外植体经噻重氮苯基脲（ＴＤＺ）诱导后,即产生不定芽和形成试管绿苗营养系,营养系经过多聚酶链反应（ＰＣＲ）测定表明,约有     

青山羊生后生长发育的研究

青山羊素以多胎高产和生产优质羔皮而称，羔羊初生体重较小，是成年母羊的7.73%，公羔比母大11.26％（P＜0.05），冬羔比秋羔大45.45％（P＜0.01）。公、母羔生后40天出现第一次生长受阻，40天以后母羔比公羔-受阻次数多，这与其早熟、早配和早产有关，成年公、母羊的体重分别为24.33±1.74和20.33±0.46kg，达到成年体重95％的月龄分别是24.17和32.78。公羊比母羊早熟，且体尺发育上先胸围、体长，再体高，但母羊的体尺在1月龄时占成年羊的比例略比公羊高，这可能对其早孕多胎是有利的。     

胎次、配种及分娩月份对母猪繁殖性能的影响

选择福建某种猪场2010年8月至2013年12月14 466窝二元母猪,分析其繁殖性能,研究不同胎次、选配月份、分娩月份对母猪生产性能的影响.结果表明:6胎的总产仔数、产活仔数、配种分娩率显著高于1胎(P0.05);5月份配种、9月份分娩的母猪生产性能最低;6~8月份因高温应激导致正常发情率比较低、返情率比较高,11~12月份配种的母猪繁殖性能最高.     

不同品种及月龄牛肉品质的比较研究

在相同营养模式下随机选取高代安杂公犊、高代新褐杂公犊和荷斯坦奶用公犊10、12、18月龄牛各3头进行屠宰,分别取左胴体的背最长肌、臀中肌、半腱肌、股外侧肌作为肉品质试验样品,在实验室进行肉样品质理化性状分析。结果表明:牛肉品质在不同的品种、不同的部位、不同的年龄上都存在相当大的差异,年龄对肌肉的组成与结构都产生了一定的影响,在生产与消费过程中,应将年龄作为评价肉品质的重要指标之一。     

大肠杆菌K88的黏附性与仔猪初生重、断奶重和日增重的关系

研究利用3个品种(大白、长白和松辽黑猪)共366头35日龄左右断奶仔猪的小肠样品与大肠杆菌K88ab、K88ac、K88ad进行黏附实验,并且利用SAS8.2对不同黏附类型仔猪的初生重、35日龄断奶重以及断奶前日增重进行了方差分析。结果表明:弱黏附归属不同时,其分析结果都是一致的,即黏附型仔猪与非黏附型仔猪的初生重、35日龄断奶重和断奶前日增重都没有显著差异(P>0.05)。     

DNA Polymorphisms of 5′-Flanking Region of Insulin-Like Growth Factor 1 Gene and Their Association with Reproduction Traits in Goats

Research on the identity of genes and their relationship with traits of economic importance in farm animals could assist in the selection of livestock.In this study,the polymorphisms of insulin-like growth factor 1 (IGF1) gene in 561 goats often breeds were detected by polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) and their association with litter size and birth weight in three breeds were investigated.The effects of IGF1 polymorphisms on the breeding value for litter size and birth weight were examined using least square methods.Two deletions (CA) were detected in the microsatellite and two mutations (A1637G,T1640C) were found in 5’-flanking regulatory region.No significant association between the polymorphisms in 5’-flanking region oflGF1 and birth weight was found in the three breeds of goats.In Gulin Ma goats,two polymorphisms were found to affect litter size traits.In Chuandong White goats and Guizhou White goats,no significant difference (P＜0.05) in litter size between goats carrying different genotypes was observed.Further evaluation and confirmation studies in more goat populations with larger sample sizes are necessary.     

纯种和牛快速扩繁关键技术研究

为达到快速扩繁纯种和牛的目的,试验从供体牛高强度超数排卵、胚胎性别鉴定及不同品种受体牛移植对产犊、妊娠期和犊牛初生重的影响进行研究。结果表明,纯种和牛连续超排9次,每次间隔30 d,第2次头均回收胚数22.78枚,显著高于第5~9次结果（P< 0.05）,其余各组之间无显著差异（P> 0.05）;第1~3次头均可用胚数分别为8.67、13.78、8.56枚,组间无显著差异（P> 0.05）,第2次头均可用胚数显著高于第4~9次头均可用胚数（P< 0.05）,极显著高于第7、9次头均可用胚数（P< 0.01）。性别鉴定胚胎和常规胚胎移植妊娠率和产犊率差异均不显著（P> 0.05）,性别鉴定胚胎的母犊率为95.56%。西门塔尔杂交牛受体产犊率高于和牛杂交牛、荷斯坦奶牛受体,但差异不显著（P> 0.05）。和牛杂交牛受体妊娠期极显著高于西门塔尔杂交牛和荷斯坦奶牛受体（P< 0.01）,西门塔尔杂交牛和荷斯坦奶牛之间差异不显著（P> 0.05）;西门塔尔杂交牛受体所产和牛母犊初生重显著高于和牛杂交牛受体（P< 0.05）,极显著高于荷斯坦奶牛受体（P< 0.01）,3个品种受体牛产和牛公犊初生重之间差异不显著（P> 0.05）;同一品种受体牛其产公、母犊牛的妊娠期及初生重均相近。     

Arterial blood gas parameters of normal foals born at 1500 metres elevation

Reasons for performing study: Arterial blood gas analysis is widely accepted as a diagnostic tool to assess respiratory function in neonates. To the authors' knowledge, there are no published reports of arterial blood gas parameters in normal neonatal foals at altitude. Objective: To provide information on arterial blood gas parameters of normal foals born at 1500 m elevation (Fort Collins, Colorado) in the first 48 h post partum. Hypothesis: Foals born at 1500 m will have lower P_aO₂ and P_aCO₂ than foals born at sea level due to low inspired oxygen and compensatory hyperventilation occurring at altitude. Methods: Sixteen foals were studied. Arterial blood gas analysis was performed within 1 h of foaling and subsequent samples were evaluated at 3, 6, 12, 24 and 48 h post partum. Data were compared to those previously reported in healthy foals born near sea level. Results: Mean P_aO₂ was 53.0 mmHg (7.06 kPa) within 1 h of foaling, rising to 67.5 mmHg (9.00 kPa) at 48 h post partum. P_aCO₂ was 44.1 mmHg (5.88 kPa) within one hour of foaling, falling to 38.3 mmHg (5.11 kPa) at 48 h. Both P_aO₂ and P_aCO₂ were significantly lower in foals born at 1500 m elevation than those near sea level at several time points during the first 48 h. Conclusions and potential relevance: Foals at 1500 m elevation undergo hypobaric hypoxia and compensatory hyperventilation in the first 48 h. Altitude specific normal arterial blood values are an important reference for veterinarians providing critical care to equine neonates.     

永丰草地畜牧业生产系统分析

运用线性规划模型，对甘肃省天祝藏自治县永丰草地的畜牧业生产进行了系统分析。结果表明在保持现有牦牛、绵羊头数（年１８０６７头、羊２６９１２只，总载畜量１１７２４７羊单位）和人工草地（１３３ｈｍ＾２）时，仅调整畜群结构，可使纯收益增加２０％。