湖北省江陵县猫日本血吸虫感染情况调查

以饱和食盐水漂浮虫卵法、顶管毛蚴孵化法检测猫日本血吸虫的感染情况。结果显示,饱和食盐水漂浮虫卵法检测阳性率为7.82%;粪便毛蚴孵化法检测阳性率为6.80%;含5-9个毛蚴杯子数占总杯数的17.35%。结果提示,血吸虫病的老疫区江陵县猫轻度感染日本血吸虫。     

湖北荆州部分地区家鸭毛毕吸虫病的调查

为了解湖北荆州太湖港水域家鸭毛毕吸虫病流行现状,用血清学诊断法、顶管毛蚴孵化法和饱和食盐水漂浮虫卵法等检测了家鸭毛毕吸虫感染情况。结果显示,血清学检查阳性率为5.26%,饱和食盐水漂浮虫卵法检查阳性率为5.48%,粪便毛蚴孵化法检查阳性率为6.84%。研究结果表明,该地区存在家鸭毛毕吸虫病。     

湖北荆州部分地区家鸭毛毕吸虫病调查

为了解湖北荆州太湖港水域家鸭毛毕吸虫病流行现状,用血清学诊断法、顶管毛蚴孵化法、饱和食盐水漂浮虫卵法等检测了家鸭毛毕吸虫感染情况。结果显示,血清学检查阳性率为5.26%,饱和食盐水漂浮虫卵法检查阳性率为5.48%,粪便毛蚴孵化法检查阳性率为6.84%。结果提示,该地区存在家鸭毛毕吸虫病。     

湖北荆州部分地区羊血吸虫病流行病学调查

用血清学诊断法、顶管毛蚴孵化法、饱和食盐水漂浮虫卵法等检测湖北荆州部分地区羊血吸虫感染情况。结果显示,血清学检查阳性率为16.88%,饱和食盐水漂浮虫卵法检查阳性率为17.46%,粪便毛蚴孵化法检查阳性率为13.57%。提示在血吸虫病的老疫区,羊血吸虫病以中、轻度感染居多。     

湖北省石首市麋鹿血吸虫病流行现况的调查

目的了解石首市糜鹿血吸虫病流行情况。方法选择湖北省石首市天鹅洲的3个地区的麋鹿为研究对象,用直接毛蚴孵化法、顶管毛蚴孵化法、饱和食盐水虫卵漂浮法检测验麋鹿的感染情况,并对石首天鹅洲故道旁钉螺进行调查。结果直接毛蚴孵化法检查阳性率为16.0%,顶管毛蚴孵化法检查阳性率为12.0%,饱和食盐水虫卵漂浮法阳性率为12.0%,石首天鹅洲钉螺阳性率平均为4.8%。结论结果显示,该市天鹅洲麋鹿血吸虫感染为主。     

湖北省江陵县湖滩地区牛日本血吸虫病流行特征的研究

选择湖北省江陵县5个行政村的水牛和黄牛，用血清学诊断法、饱和盐水漂浮虫卵法、顶管毛蚴孵化法检测日本血吸虫感染情况，并采用抽样法对调查村所属的湖滩钉螺分布情况进行了检查。结果，牛日本血吸虫病血清抗体检查阳性率为17．92％，饱和盐水漂浮虫卵法检查阳性率为19．46%，粪便毛蚴孵化法检查阳性率为16．04%，5个村湖滩钉螺的平均密度为0．445只／m^2。结果显示，该县日本血吸虫病流行严重。     

冷冻等处理对不同孵化进程的卤虫卵存活率的影响

本文研究了冷冻、双氧水和干燥处理对处于不同孵化进程中的卤虫卵的存活率(孵化率)的影响。冷冻对未经孵化处理的卵的孵化率影响很小。冷冻1w～8w,基本保持不变。孵化进行了3h的卤虫卵,冷冻8w后,其孵化率降低了10个百分点。孵化进行了6h的卤虫卵,冷冻8w后,其孵化率降低了31个百分点。孵化进行了9h的卤虫卵,冷冻8w后,其孵化率降低了40个百分点。处于不同孵化阶段的卤虫卵经冷冻处理8w后,再经3%双氧水处理10min和40℃干燥处理6h,其孵化率表现为不同的特点。未经孵化处理的卵的孵化率基本保持不变。孵化进行了3h的卤虫卵,其孵化率再次降低5个百…     

河池市散养牛寄生虫感染情况调查

为了解河池市散养牛的寄生虫感染情况,利用饱和盐水漂浮法、水洗沉淀法、毛蚴孵化法对采自河池市6个县(市、区)1 200头牛的粪便进行寄生虫检查。结果显示,粪便寄生虫总阳性率为76.5%,分别检出了前后盘吸虫卵、片形吸虫卵、线虫卵、螨虫卵和球虫卵囊,其阳性率分别为47.58%、7.25%、32.67%、9%和18.91%,未检出日本血吸虫毛蚴。结果表明,预示我市目前散养牛群中寄生虫的感染情况比较严重。     

湖北荆州地区牛血吸虫病流行病学调查

用血清学诊断法,顶管毛蚴孵化法,饱和食盐水漂浮虫卵法等检测湖北荆州地区牛血吸虫感染情况。结果显示,血清学检查阳性率为17.92%,饱和食盐水漂浮虫卵法检查阳性率为19.46%,粪便毛蚴孵化法检查阳性率为16.04%。提示,阳性牛以重、轻度感染居多,该地区是血吸虫病的老疫区,牛血吸虫病比较严重。     

某种牧草提取物对日本血吸虫虫卵肉芽肿的影响

日本血吸虫病的病理基础是在肝、肠所形成的虫卵肉芽肿,其形成机理已被证明是免疫反应。吡喹酮对血吸虫成虫、童虫、尾蚴和毛蚴均有强大的杀灭或抑制作用,对虫卵作用尚有争论,在生产中还发现一些植物具有灭螺作用。笔者等筛选了抑制钉螺繁殖的高蛋白牧草进行了研究。本实验对比观察吡喹酮与灭螺牧草对小鼠肝脏内日本血吸虫虫卵肉芽肿的作用及对肉芽肿内嗜酸性粒细胞的影响。     

不同限饲水平对产蛋期肉种鸭生产性能的影响

本研究旨在探讨不同限饲水平对产蛋期肉种鸭生产性能和孵化指标的影响。试验选取 ４０周龄父母代 ＳＭ３樱桃谷种鸭 ３２００只（母鸭 ２６００只,公鸭 ６００只）,随机分成 ４组,每组 ５个重复,每个重复 １６０只鸭（母鸭 １３０只,公鸭 ３０只）。以玉米 －豆粕 －小麦型配合饲料（代谢能 １１．５０ＭＪ／ｋｇ,粗蛋白质 １８．００％）为基础饲粮。Ｔ１组日饲喂料量最大,为每只鸭 ２２５ｇ,其他组依次降低 １５ｇ,分别为 ２１０（Ｔ２组）、１９５（Ｔ３组）和 １８０ｇ（Ｔ４组）,试验期 ３５ｄ。结果表明：１）当日饲喂料量由２２５ｇ下降到２１０ｇ时,公、母鸭的体增重均显著下降（Ｐ＜０．０５）,产蛋率略有上升,蛋重略有下降,但二者变化均不显著（Ｐ＞０．０５）,当日饲喂料量继续下降到 １９５和 １８０ｇ时,与日饲喂料量 ２２５ｇ时相比,公、母鸭体增重、产蛋率和蛋重均显著下降（Ｐ＜０．０５）;２）经回归分析,公、母鸭体增重、产蛋率、蛋重与日饲喂料量有显著的直线或二次曲线关系（Ｐ＜０．０５）,产蛋率与蛋重之间也有显著的二次曲线关系（Ｐ＜０．０５）;３）日饲喂料量对种鸭死淘率及种蛋合格率、受精率、健雏率、入孵蛋孵化率和受精蛋孵化率均无显著影响（Ｐ＞０．０５）。结果提示,适当限制饲喂料量可降低体增重,提高产蛋率,但过度限饲会影响生产性能。     

蛋重对蛋鸭孵化效果的影响

将三个品种(攸县麻鸭、麻旺鸭和三穗鸭)种鸭蛋按蛋重各分5个组在相同的条件下孵化,研究蛋重对不同品种孵化效果的影响。结果表明,种蛋受精率和入孵蛋孵化率:攸县麻鸭蛋重在65~73 g最高,麻旺鸭蛋重在66~70 g最高,三穗鸭蛋重在66~74 g最高,种蛋过重或过轻均不利于种蛋孵化。胚胎死亡率:攸县麻鸭在蛋重61~65 g最低,三穗鸭在蛋重小于62 g时最低,麻旺鸭在蛋重小于58 g时最低,攸县麻鸭种蛋重量适中有利于胚胎成活,三穗鸭和麻旺鸭种蛋重量较轻时有利于胚胎成活。     

Experimental infection of ducks with Mycoplasma synoviae

Specific-pathogen-free ducks 24 and 180 days old were inoculated intranasally with the WVU 1853 strain of Mycoplasma synoviae (MS). No significant gross lesions were found in the infraorbital sinus, trachea, or air sacs at 7 or 28 days postinfection (PI), although MS was recovered from all these organs. A few ducks responded serologically by developing agglutinating antibodies. MS multiplied in embryonated duck eggs but to lower titers than in embryonated chicken eggs.     

Selection responses in duration of fertility and its consequences on hatchability in the intergeneric crossbreeding of ducks

1. From 1992 to 2003, selected (S) and control lines (C) of the laying Brown Tsaiya duck (Anas platyrhynchos) were simultaneously maintained under the same standardised conditions of feeding and management. 2. The selection objective was to increase the number of fertile eggs after a single artificial insemination (AI) with pooled Muscovy semen. From generations G1 to G11, 2452 and 2022 female ducks, in S and C lines, respectively, were measured and recorded. In the S line, the percentage selected varied between 20.2 and 34.3% in females and between 7.2 and 20.8% in males. 3. Selection for number of fertile eggs had a correlated effect of increasing the parameter tau of the logistic curves which fitted the daily variations (d 2 to 15) in fertility or hatchability on the basis of eggs set. The differences S-C for the estimates of the times of half maximal fertility and hatchability increased by 0.41 and 0.37 d per generation between G1 and G11, respectively. 4. The highest increases of fertility per day rates after a single AI were observed between d 5 and 11. Moreover, in the selected line, fertility rate was higher than, or equal to, 90% in d 2 from G8. The same tendencies were observed for the changes in the evolution of hatchability on the basis of eggs set. 5. Selection increased fertility and hatchability according to the egg set rates, especially for d 2 to 8 after AI. Hatchability of fertile eggs was not impaired, confirming that selection for one AI per week was possible in this strain of laying ducks.     

Vertical transmission of duck plague virus (DPV) by apparently healthy DPV carrier waterfowl

Duck plague virus (DPV) was transmitted vertically in muscovy, pekin, and mallard ducks that were persistently infected with the LA-SD-73, MSN-WI-77, or CO-WI-73 isolates of DPV. The effects of vertical transmission on the fertility and hatchability of eggs laid by DPV carrier ducks varied with the DPV isolate and duck species. Fertility was reduced significantly only in eggs laid by MSN-WI-77 virus carrier pekin and muscovy ducks. The hatchability of eggs laid by DPV carrier mallards and muscovies was significantly reduced from that of uninfected control ducks. All ducklings tested that hatched from eggs laid by DPV carrier waterfowl shed DPV in the feces. The DPV carrier ducklings shed DPV in small amounts. Vertical transmission of DPV in domestic flocks can lower fertility and hatchability. In wild waterfowl, vertical transmission may be a means of virus perpetuation from generation to generation.     

Experimental infection of ducks with Mycoplasma gallisepticum

Specific-pathogen-free ducks 24 and 180 days old were inoculated intranasally with the S6 strain of Mycoplasma gallisepticum (MG). No significant gross lesions were found in trachea, lung or air sacs at 7 or 28 days postinfection (PI). MG was recovered from the infraorbital sinus and trachea but not from the air sacs 7 and 28 days PI. A few ducks responded serologically by developing agglutinating antibody. MG multiplied in embryonated duck eggs but to lower titers than in embryonated chicken eggs.     

Prevalence of anti-Toxoplasma gondii antibodies in serum and aqueous humor samples from cats with uveitis or systemic diseases in France

The present study sought to elucidate whether Schistosoma japonicum eggs could survive a passage through dogs and chickens. Three dogs and three chickens were used for the experiment. The dogs were allowed to eat goat faeces containing 80 S. japonicum eggs per gram. The chickens were given 2 ml of water containing more than 100 S. japonicum eggs per ml. The hatchability of the eggs was 51.8% prior to administration. All faeces were collected for 3 days from the dogs and for 2 days from the chickens and egg excretion and hatchability were measured. The results showed that nearly 50% of the eggs administered to the dogs were recovered in the faeces during the first 2 days and during the first 25 h 39% of the recovered eggs were viable and able to hatch. In the chickens 9% of the administered eggs were recovered within 27 h and within the first 3.5 h after administration 19% of the recovered eggs were viable and able to hatch. The results suggest that both dogs and chickens may act as transport hosts for S. japonicum in endemic areas.     

Inheritance of reproductive traits of female common ducks (Anas platyrhynchos) in pure breeding and in inter-generic crossbreeding with muscovy ducks (Cairina moschata)

1. Genetic parameters of reproductive traits were estimated in a population of common duck, in purebreeding and crossbreeding (with Muscovies) insemination systems. A total of 989 females were studied over three generations as well as 4025 purebred offspring and 4,125 male mule offspring. 2. Traits studied were age at first egg, total number of eggs laid until the age of 48 weeks, fertility and hatchability rates in pure and crossbreds, weight at 6 and 30 weeks of age, average egg weight and body weight of the male mule ducks at 6 weeks of age. 3. Heritability estimates were found to be medium range for reproductive traits (0.15 to 0.47). Heritability value for fertility or hatchability in crossbreds was twice as high as in purebreds (0.32 vs 0.15 for fertility; 0.36 vs 0.16 for hatchability). 4. Fertility in purebreeding and in crossbreeding were two different traits (r(g) = 0.49) while hatchability displayed a high genetic correlation between breeding systems (r(g) = 0.88). 5. Genetic correlations with number of hatched mule ducks were medium or high and favourable. Genetic correlations between reproductive traits and weights were low (< 0.36), the most related trait being the body weight of the male mule duck at 6 weeks of age.     

高海拔环境下不同品种鸡种蛋孵化效果研究

为评价不同品种鸡种蛋在高海拔地区的孵化性能,选取4个品种蛋鸡的种蛋在海拔3 780 m的环境条件下开展孵化试验,观察并比较高海拔环境下各品种鸡种蛋的孵化效果。结果表明,拉萨白鸡种蛋的受精率、入孵蛋孵化率、受精蛋孵化率、健雏率都是最高的,分别为94.32%、76.70%、81.33%、94.41%;北京藏鸡种蛋的受精率最低,为74.00%;北京油鸡种蛋的入孵蛋孵化率、受精蛋孵化率、健雏率都是最低的,分别为0.84%、1.00%、50.00%。     

Susceptibility of ducks and duck-origin cell cultures to infectious bursal disease virus

Specific-pathogen-free (SPF) ducks that were 1, 3, 4, 7, 10, 30, and 180 days old were inoculated experimentally orally or nasally with infectious bursal disease virus (IBDV). Attempts to induce clinical disease in ducks with strain J1 or FK-78 of IBDV were unsuccessful. Virus-recovery attempts from organ and intestinal contents were also unsuccessful. No significant gross or histopathological lesions were found in liver, spleen, kidney, heart, or bursa of Fabricius of 1- and 3-day-old ducks at 4 or 7 days postinoculation. The ratios of bursa weight to body weight of 1-, 10-, and 30-day-old inoculated and control ducks revealed no difference at 21 days postinoculation. The ducks responded serologically, however, by developing both virus-neutralizing and agar-gel-precipitin antibodies. Virus multiplied in embryonated duck eggs and duck embryo fibroblast cells but not in duck kidney cells.