不同饲养基质对豆天蛾越冬影响的研究

研究豆天蛾的越冬条件,以便为饲养繁殖豆天蛾提供科学依据。以纯土、蘑菇料土、锯末土和纯锯末为豆天蛾越冬的饲养基质,通过用4种饲养基对豆天蛾的室内、室外处理发现,室内处理的豆天蛾化蛹率为纯锯末>锯末土>蘑菇料土>纯土,死亡率为纯锯末>纯土>蘑菇料土>锯末土;室外处理的豆天蛾化蛹率为纯锯末>锯末土>蘑菇料土>纯土,死亡率为纯土>蘑菇料土>纯锯末>锯末土。研究结果表明,饲养基质中有机质的含量影响豆天蛾的化蛹率和死亡率,豆天蛾趋向于含有有机质较多的饲养基质中越冬。     

云南热带雨林地区野猪生物学特性与驯养方法

为了解云南热带雨林地区野猪的生物学特性与驯化技术,探讨野猪的规模化养殖与开发利用。通过野外实地调查和收集2~4个月体重约5~8 kg的16头野猪,按试验要求与同等体重家猪人工混养驯化2年时间,将试验中观察的野猪部分生物学特性和驯化方法进行总结,整理成可供推广应用的野猪驯化管理模式。结果表明:西双版纳热带雨林地区野猪适应性强,喜集群活动,驯化后性情和食性会发生改变,可全年发情,提高繁殖性能和生长速度。在增加防护措施和户外运动场所的基础上,可参照家猪饲养方法,对纯种野猪进行家养或将纯种公野猪与母家猪进行杂交利用,开发生产无公害优质野杂猪。     

婆罗门牛及其杂交优势利用研究

婆罗门牛的引进、与本地黄牛杂交利用,对原种牛及其杂交牛的生产性能等进行分析。结果表明,婆罗门牛是适应热带、亚热带生态环境饲养的肉牛品种,其杂交牛的杂交优势明显,在生长、繁殖、产肉性能等方面表现较好,值得大力推广应用。     

Reproductive Performance and Reconception of Nellore Cows According to Their Pure‐ or Cross‐Bred Calves

The objective of the present research was to evaluate the effect of a calf's genetic group on the productive and reproductive efficiency of its Nellore dam. Fixed‐time artificial insemination was applied to 800 cows using semen extracted from Nellore, Simmental and Angus Red bulls. Four hundred eleven cows calved, producing 119 Nellore, 103 ½Simmental–½Nellore and 189 ½Nellore–½Angus Red calves. The second mating period, which paired Nellore cows with Simmental bulls, was initiated 10 days after parturitions began and lasted for 5 months. Based on the two successive parturitions, the cumulative parturition rate for calving periods of 3, 4 and 5 months was calculated. Although no significant difference was observed for birth weight among the genetic groups, cross‐bred calves weighed, on average, 10% more than did pure‐bred calves at the age of 205 days. Nellore dams experienced a gestation period that was 7 days longer than did the cross‐bred dams, and the former showed a higher parturition rate at 90 and 120 days of the calving season, but not at 150 days (calving rates of 80.6, 76.4 and 76.2% for mothers of Nellore, ½Nellore–½Angus Red and ½Nellore–½Simmental, respectively, p > 0.05). At 90 and 120 days, Nellore dams produced more kg of calf per mated dam. In conclusion, in a short breeding season, Nellore dams nursing pure‐bred Nellore calves were found to have a higher biological efficiency compared with Nellore dams nursing cross‐bred calves.     

Survey of dirofilariasis among dogs in seremban,Malaysia

A total of 370 dogs from the District Veterinary Office in Seremban, Malaysia, was examined for dirofilariasis. An overall incidence of infection of 32.4% was observed, but pure bred dogs showed a slightly higher incidence of infection (39.2%) and a higher parasitaemia, whereas mixed bred dogs were less frequently infected (27.4%) and usually had a lower parasitaemia. In addition, short-haired pedigree dogs such as boxers, Dobermanns, dachshunds and bulldogs were generally more frequently infected and showed a higher parasitaemia than longer-haired pedigree dogs, such as Alsatians, spaniels and terriers. There was no significant difference in distribution of infection among dogs of different sexes and age groups.     

不同营养对蜜蜂初生重的影响

分别利用不同花粉饲料制作的粉脾饲喂蜂群，测定后代蜜蜂的初生体重。结果表明．饲喂花粉与饲喂花粉＋20％豆粉的蜂群相比，其所育工蜂初生重差异不显著，蜂王初生重差异显著，雄蜂初生重差异极显著；饲喂花粉和饲喂花粉＋20％豆粉的蜂群，其后代与饲喂豆粉的蜂群相比，差异均为极显著；饲喂豆粉的蜂群，群势逐渐衰落，甚至不能培育出雄蜂个体。因此，建议在蜜蜂饲养工作中使用纯正花粉饲料饲喂蜂群，以保证蜜蜂的质量和蜂群的产量。     

牧原猪的二元轮回杂交育种体系的形成与发展

终端消费者的需求始终是牧原养猪生产的导向,其目的在于实现猪肉生产链各成员价值最大化。传统的用两个纯种杂交来生产二元杂种母猪的金字塔模式被打破,从2002年开始建立了以长白和大白两个品种为亲本的二元轮回杂交育种体系,通过持续的选育,牧原集团培育出来的用于轮回杂交的长白和大白母本品种（品系）以及相应的父本品种（品系）均具有自己鲜明的特色,形成了在生长速度和繁殖性能等方面令养猪生产者满意,在瘦肉率和胴体品质等方面令消费者满意的杂种优势好、遗传性稳定的二元轮回杂交育种体系。     

法系夏洛来牛的引进繁育(上)

1986年后我站相继从国内、外引进法国夏洛来牛9头,在4头母牛基础上开始纯繁自育发展牛群。截至2003年6月,繁殖犊牛87头,存栏62头,其中成年公、母牛45头。4岁龄纯繁公、母牛平均体尺体重与同龄原种牛比,均有所提高。纯繁公牛20月龄采精调教,平均利用年限为61.73月龄,生产冻精71 074剂,淘汰年龄平均为84.6月龄。母牛平均初孕年龄为25.16月龄,平均淘汰年龄为95.71月龄,终生产犊4.8头。为社会创造巨大经济效益。     

Genetic correlation between performance of pure‐bred white leghorn pullets and their paternal half‐sisters from Rhode Island red dams

The genetic correlations for age at first egg, part‐year egg production, egg weight and body weight at 20 weeks were high and positive in pure‐breds and their cross‐bred half‐sibs. This indicates that the performance of the cross between White Leghorn and Rhode Island Red can be further improved through intra‐population selection for these characters in the two parental breeds.     

Prevalence of the breed-related glaucomas in pure-bred dogs in North America

Objective To determine the prevalence of the breed‐related glaucomas in pure‐bred dogs presented to the veterinary medical teaching hospitals in North America that participate in the Veterinary Medical Data Base (VMDB). Materials and methods In this retrospective study, age of first diagnosis, breed, and gender data for all breeds of dogs were collected from the VMDB with the clinical diagnosis of primary glaucoma (glaucoma‐NOS) at 5–10 year intervals from 1964 to 2002. The prevalence for each breed (affected dogs compared to all dogs of each breed), any changes over the 38 years, and any gender differences for these glaucomas were determined. Results The prevalence of the primary breed‐related glaucomas has gradually increased from 0.29% (1964–1973); 0.46% (1974–1983); 0.76% (1984–1993); to 0.89% (1994–2002). Breeds that consistently featured among the highest 10 for glaucoma prevalence from four different periods (1964 to 2002) included American Cocker Spaniel, Basset Hound, Wire Fox Terrier, and Boston Terrier. During the last observation period (1994–2002), 22 different breeds had 1% or higher prevalence of the glaucomas. The highest prevalence of glaucomas in 1994–2002 by breed included: American Cocker Spaniel (5.52%); Basset Hound (5.44%); Chow Chow (4.70%); Shar‐Pei (4.40%); Boston Terrier (2.88%); Wire Fox Terrier (2.28%); Norwegian ElkHound (1.98%); Siberian Husky (1.88%); Cairn Terrier (1.82%); and Miniature Poodle (1.68%). A predominance of females with glaucoma occurred in the American Cocker Spaniel, Basset Hound, Cairn Terrier, Chow Chow, English Cocker Spaniel, Samoyed, and perhaps the Siberian Husky, and a predominance of males in the Australian Cattle dog and St Bernard. Age affected the time for first presentation of the glaucomas in the pure‐bred dog. In the majority of breeds the glaucomas were presented for initial diagnosis in dogs between 4 and 10 years of age. Conclusion Breed‐related glaucomas in pure‐bred dogs are frequently presented to the veterinary medical teaching hospitals in North America. The prevalence of the breed‐related glaucomas in the dog appears similar to humans, and in some breeds exceeds that in humans. In many breeds the high prevalence of the glaucomas suggests a genetic basis.     

Estimates of genetic parameters associated with lactation feed intake and growth and composition traits measured during a performance test

Days to reach 113.4 kg, adjusted backfat depth and adjusted loin muscle area to 113.4 kg were evaluated on pure‐bred Landrace (n = 15 660) and Yorkshire (n = 14 808) boars and gilts. Daily lactation feed intake (LFI) was recorded within parity records from pure‐bred Yorkshire (n = 1587) and Landrace (n = 2197) females during day 1–22 of lactation, and LFI curves were predicted using a mixed model. Evaluation of feed intake differences between 2 consecutive days of lactation resulted in the following periods: day 1–6 (PB1), day 7–10 (PB2) and day 11–18 (PB3). Average rate of change in intake (ARC), average daily intake (ADI) and variation from predicted daily LFI values (VAR) metrics were computed for each period of lactation. Gibbs sampling was used to estimate the genetic covariance between LFI metrics and grow‐finish traits. Genetic correlations were strongest between grow‐finish traits, and LFI metrics in first parity sows and were generally favourable, but correlations with LFI metrics during parity 2 or greater were low and not different from 0 (p > 0.05). Genetic correlations between LFI metrics in parity 1 sows with growth and composition traits varied greatly in strength and direction. Selection for leaner, heavier muscled gilts had a limited effect on LFI metrics. However, selection for increased growth rate was associated with higher ARC and ADI and smaller VAR values.     

The effect of Gn-RH on the pregnancy rate of artificially inseminated cows.

One hundred and nine pure bred Holstein Friesians were injected intramuscularly with 0.125 mg of a synthetic Gn-RH analogue at the time of the first service to study the effect of Gn-RH on the fertility of inseminated cows. Sixty-four cows or 58.7 per cent were diagnosed as pregnant after one insemination compared to 54 animals or 49.5 per cent in the untreated control group. Total pregnancy rate of 81.65 per cent was 8.3 per cent higher than in the controls, while the services per conception rate improved from 1.49 to 1.39. Gn-RH administration at the time of oestrus could improve herd fertility through its including effect on follicular rupture and regulatory influence on ovarian function.     

沙打旺种质资源遗传多样性RAPD分析

利用RAPD技术对我国沙打旺育成品种，地方材料和野生材料的遗传多样进行研究。结果表明，沙打旺野生材料的多态性明显高于育品种和地方材料，在13份品种（材料）中，山西沁野生沙打旺基因多样性最大，山西五台山野生沙打旺多态位点比例最高，沙打旺生材料总基因多样性和平均基因多样性均大于育成品种和地方材料，其遗传变异幅度最大，而育成品种最小，沙打旺野生材料间遗传分化明显，其基因分化系数比育成品种和地方材料间大。     

The impact of fish and drought on frog breeding in temporary waters in Zimbabwe

The breeding of frogs in four ponds near Harare, Zimbabwe, was investigated during a wet rainy season (2000/01) and a dry one (2001/02). During 2000/01 eight and nine species bred in two ponds in abandoned gravel pits that never contained fish, but only four species bred in these in 2001/02 and the relative abundance was reduced by about 50%. Pond 3 was a small dam that filled after the rains and was invaded by fish once it overflowed. Five species bred in it in 2000/01, but breeding activity was curtailed once it was invaded by catfish, Clarias gariepinus, some of which were found with frog remains in their stomachs. The pond did not overflow in the following season, and was therefore not invaded by fish; although only four species bred in it their relative abundance was considerably higher. Pond 4 was a permanent pond that always contained fish. Only three species bred in it and the relative abundance of tadpoles was always low. Species belonging to the Ranidae seemed to be most severely affected by drought and this may explain the absence of some species, such as the African bullfrog, Pyxicephalus adspersus, that was once abundant around Harare.     

Comparison of productive and reproductive performance and hair cortisol levels between Brown Swiss cross‐bred and Holstein cows housed in the same barn

The productive and reproductive characteristics of Brown Swiss (B) cross‐bred cows were investigated by comparing with those of Holstein (H) cows housed in the same barn. Additionally, their hair cortisol levels were analyzed to evaluate the extent of stress experienced during dry and lactation periods. B cross‐bred cows had lower milk yields and higher milk fat rates than H cows. Reproductive records showed that days from parturition to first artificial insemination (AI) in B cross‐bred (n = 16) and H (n = 27) cows were not significantly different, but conception rate at first AI of B cross‐bred cows tended to be higher than that of H cows. Percentage of B cross‐bred cows that resumed ovarian cyclic activity within 45 days after parturition was higher than that of H cows (6/6 (100%) and 5/11 (45.5%), P < 0.05), and B cross‐bred cows had higher body condition scores at that time. Hair cortisol level at 60 to 90 days after parturition in H cows increased significantly compared with in the dry period, and it was higher than that of B cows during the same period. These results suggest that B cross‐bred cows experience less metabolic stress during early lactation, which may result in earlier resumption of reproductive function.     

隐性白羽肉鸡(农大系)与黑羽地方鸡种杂交效果分析

隐性白羽肉鸡 (农大系 )是中国农业大学利用从法国引进的快大型肉鸡选育而成的隐性白纯系 ,具有隐性白基因纯合 ,生长速度快 ,饲料转化率高等特点。本实验将这一隐性白品系与某地方优质兼用型鸡种———该鸡种具有肉质风味好 ,黑羽、黑胫等特征 ,做正反交杂交试验 ,并使用两种饲料营养水平作对比 ,对隐性白与地方鸡种杂交生产优质商品肉鸡的效果进行了分析。结果表明 ,以地方鸡为父本 ,隐性白羽肉鸡为母本杂交效果好 ,杂种鸡肉质明显优于快大型肉鸡 ,生长速度在 9周龄达到 1 .5kg ,符合半优鸡上市要求 ,并且 ,杂种鸡保持了地方鸡种的黑羽、青脚等外貌特征 ,该杂交组合还可通过胫色自别雌雄。     

陕北白绒山羊繁育中心羊场绒山羊日粮的评价

试验选择陕北白绒山羊繁育中心羊场的成年健康母羊（怀孕前期）16只,育成母羊13只,育成公羊13只,空腹称重。测定每只羊1d的采食量,计算其摄入的营养成分含量,并与原苏联绒用山羊饲养标准比较,进行饲养水平评价。结果显示,与饲养标准比较,陕北白绒山羊繁育中心羊场的育成母羊代谢能高2．68MJ,粗蛋白低59．29g,钙低3．00g,磷低1．52g;育成公羊代谢能高3．47MJ,粗蛋白低81．92g,钙低4．42g,磷低2．62g;成年母羊代谢能高2．51MJ,粗蛋白低91．33g,钙低3．09g,磷低1．93g。结合羊的体况综合评价饲养水平基本合理,但尚需要按饲养标准增加粗蛋白、钙、磷等营养物质的供给量。     

Reproductive performance of totally confined sheep bred with semen extended in a lactose-egg yolk-glycerol buffer and stored at 5 degrees C.

Two experiments were carried out in January and May 1975 to study reproductive performance (fertility, prolificacy and fecundity) of totally confined sheep synchronized for estrus. The main objective of the first experiment was to compare reproductive performance of ewes bred naturally to those bred by artificial insemination. Semen for artificial insemination was collected by either artificial vagina or electroejaculation and stored for up to 36 hours at 5 degrees C. A second objective was to evaluate the effect of pregnant mares' serum gonadotrophin on the reproductive performance of ewes synchronized for estrus. Fertility was 53% for ewes bred by natural mating, 34% for ewes receiving pregnant mares' serum gonadotrophin and bred by artificial insemination, and 9% for those not receiving pregnant mares' serum gonadotrophin and bred by artificial insemination. There was no difference in fertility between ewes bred with semen collected by artificial vagina or by electroejaculation. A similar pattern was observed for fecundity. Average prolificacy was 2.0 with no significant differences among mating methods or pregnant mares' serum gonadotrophin application being observed. In the second experiment, the reproductive performance of ewes inseminated with semen stores at 5 degrees C for 48 to 60 hours was compared to that of ewes inseminated with semen stores for 24 to 36 hours. No significant differences in the reproductive performance were detected. Although average fertility (9%) and fecundity (19%) were low, prolificacy averaged 2.0 lambs per ewe lambing.     

苏尼特羊育成羊屠宰性能研究

为了探讨地方良种肉羊选育提高工作的经济效益和社会效益,开展了苏尼特羊育成羊屠宰试验。结果表明,苏尼特羊育成母羊和育成羯羊的平均宰前活重、屠体重和净肉重分别达到47.70、22.50、17.60 kg和51.60、25.00、19.60 kg,屠宰率和净肉率分别达到47.10%、36.80%和48.30%、38.00%,眼肌面积分别为13.70 cm2和15.10 cm2;育成母羊和育成羯羊的净肉重、屠体重和宰前活重的变异系数也较大,分别为13.46%、12.97%、10.80%和8.11%、7.86%、6.25%。     

The effects of calving to first service interval on reproductive performance in normal cows and cows with postpartal disease

The relationships between the calving to first service interval and several measures of reproductive performance were evaluated in 1738 lactation records from cows in 32 southern Ontario Holstein herds. Lactation records were divided into three mutually exclusive health categories based on the cows' postpartal disease histories.

Relationships between the calving to first service interval and the first service conception rate, number of services per conception and open interval were similar for all three health categories. The first service conception rate was lower and the average number of services per conception higher in cows first bred before 60 days when compared to cows first bred after 60 days. The relationship between the calving to first service interval and the open interval indicated that for each day that breeding was delayed the open interval was extended by 0.86 days.

It appeared that overall conception rates may be lower for cows first bred very early or very late, but differences in the overall conception rate were only significant for cows experiencing a reproductive tract infection. Unless very expensive semen is being used, it is suggested that disease free cows be bred at the first heat occurring after 40 days postpartum, and that cows experiencing postpartal disease be bred at the first heat occurring after 60 days postpartum.