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1.
<正> 前言影响鹅蛋孵化效果的因素很多,既有外因,又有内因。在每次外因条件基本相同,研究禽蛋品质对孵化效果的影响具有重要意义,可用蛋形指数评定种蛋品质。鸡蛋蛋形指数对孵化影响试验研究报道较多,水禽种蛋蛋形指数影响研究少见报道。为探讨鹅蛋蛋形指数对孵化效果的影响,对孵化、育种工作提供依据。作者于1986年3月和1987年2月,结合生产实际,用电孵机和自制孵化器分别进行小批量试验观测,现将试验结果资料整理报道于后。  相似文献   

2.
选取288枚朝鲜鹌鹑种蛋,按蛋重、蛋形指数大小各分为3组,在相同条件下孵化,研究蛋重和蛋形指数对孵化效果的影响。试验结果表明:蛋重、蛋形指数对受精蛋孵化率的影响均极显著(P<0.01)。蛋形指数对健雏率的影响显著(P<0.05),蛋重对健雏率的影响不显著(P>0.05)。  相似文献   

3.
收集4个品种鸡的2008枚蛋观察表明:鸡蛋以锐端先产出居多(70%以上),且产蛋方位与蛋形有关(P<0.05),钝端先产出的蛋比锐端先产出的蛋形指数要大。5537枚蛋孵化试验表明:蛋形、蛋重和产蛋方位都不影响孵化率、受精率和公母比例,在生产实际中没有必要对蛋形过分挑剔。蛋形与出壳时间有关(P<0.05),蛋形指数较大,出产时间就稍迟,而且出壳时间与公母比例有关(P<0.01),出壳时间较迟的,公雏居多。21.5天出雏的公雏数是20.5天的1.5倍。观察发现,蛋形和蛋重与产蛋时间有关,上午产的蛋比下午的蛋形指数小,而蛋重大(P<0.01)。但产蛋方位与产蛋时间无关(P>0.05)。随机测量40枚白洛克发现,蛋形指数和蛋重与蛋壳厚度没有相关(P>0.05)。100枚白来航蛋资料分析表明,蛋形指数与蛋重也没有相关(P>0.05))。  相似文献   

4.
利用蛋形指数对黔东南小香鸡种蛋进行性别鉴定初步研究   总被引:1,自引:0,他引:1  
为研究黔东南小香鸡蛋形指数与性别的相关性,根据种蛋的不同蛋形和大小分成2个组:Ⅰ组种蛋231枚,平均蛋形指数R=1.36±0.045;Ⅱ组种蛋245枚,平均蛋形指数R=1.29±0.048。按组分别入孵,并对36日龄雏鸡用外貌观察法进行性别鉴定。结果表明:Ⅰ组种蛋雄性百分率为97.6%;Ⅱ组种蛋雌性百分率为93.5%,...  相似文献   

5.
研究测定了44~48周龄北京油鸡的蛋重、蛋形指数和蛋壳颜色,并分析其对种蛋孵化性能的影响。结果显示,北京油鸡蛋重、蛋形指数和蛋色均较一致;蛋重对孵化性能影响不显著(P0.05),但是随着蛋重的增加孵化性能有增加的趋势;蛋形指数对受精蛋孵化率的影响显著(P0.05),蛋形指数0.75~0.80的种蛋组显著高于其他组;蛋壳颜色对北京油鸡的受精率、受精蛋孵化率和健雏率均无影响(P0.05)。本研究结果为北京油鸡的选种提供了重要的参考依据。  相似文献   

6.
为研究贮藏方式及时间对不同颜色鸡蛋品质的影响,选取大小适中、品质良好的鸡蛋150枚,其中白、褐、粉壳鸡蛋各50枚,同种颜色鸡蛋随机分成10组,5组置于室温保存,另5组置于低温的冰箱冷藏,分别于第0、7、14、21、28天测定鸡蛋的失重率、气室高度、蛋形指数、蛋壳厚度、哈夫单位、蛋黄指数、蛋清pH、蛋壳相对重、蛋黄相对重、蛋清相对重、卵磷脂含量、蛋黄水分比、蛋清水分比和蛋比重。结果表明:白、褐、粉壳鸡蛋贮存至第14天,因贮藏方式不同,鸡蛋品质出现显著差异(P 0.05),不同颜色鸡蛋置于低温贮藏,更能有效保持鸡蛋的良好品质。  相似文献   

7.
为了研究玫瑰冠鸡蛋形指数与性别的相关性,根据种蛋的不同蛋形指数分成3组:A组平均蛋形指数R=1.29±0.03;B组平均蛋形指数R=1.36±0.03;C组平均蛋形指数R=1.40±0.03。每组取120枚玫瑰冠鸡种蛋,3个重复,即每个重复40枚。结果表明玫瑰冠鸡蛋形指数在1.36±0.03时孵化率最高;蛋形指数与性别比例无直接关系,符合遗传规律1∶1的性别比例关系。  相似文献   

8.
不同周龄和饲养方式对岭南黄鸡鸡蛋品质的影响研究   总被引:4,自引:0,他引:4  
试验比较了20周龄笼养、30周龄笼养和30周龄放养三种饲养方式下的岭南黄鸡鸡蛋品质指标:蛋重、哈夫单位、全蛋胆固醇、蛋黄指数、蛋形指数、蛋壳相对重和蛋壳厚度。试验结果表明,三组蛋形指数无显著差异;笼养条件下岭南黄鸡随着产蛋周龄的增加,蛋重增加、其他指数下降;30周龄放养鸡鸡蛋的蛋重接近20周龄笼养鸡蛋,蛋壳显著增厚,全蛋胆固醇含量高于其他两组。  相似文献   

9.
对闽南火鸡4组蛋形指数范围的种蛋孵化试验表明,蛋形指数对火鸡蛋的受精率和孵化率的影响是明显的。蛋形指数在1.50~1.59之间受影响最小,而蛋形指数在1.60以上和1.39以下受影响最大。4种指标受影响程度最大值与最小值的差分别为:受精率7.0%,受精蛋孵化率15.0%,入孵蛋孵化率12.0%,健雏率21.5%。  相似文献   

10.
为了研究鸳鸯蛋品质,试验对19枚鸳鸯蛋的蛋重、蛋形指数、蛋壳厚度等部分蛋品质参数进行了测定。结果表明:鸳鸯蛋平均蛋重为45.48 g,平均蛋形指数为1.336,平均蛋壳厚度为0.30 cm。鸳鸯蛋的蛋品质参数与鸡蛋的蛋品质参数较接近。  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

14.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

15.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

16.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

17.
The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.  相似文献   

18.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

19.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

20.
Infectious diseases have always been a terrible scourge for humans. The appearance of these plagues, as they were called without distinction, was generally connected to various conditions: asters, climatic changes or religious reasons. The concept of contagious, and then infectious, diseases came slowly. Variolation, i.e. transmission of ‘virulent’ matter to induce a natural disease and the immunity against it, was brought from Constantinople to England by Lady Montague, in 1721. This ‘variolation’ technique was also often performed in veterinary medicine against diseases like sheep-pox or pleuropneumonia. As ‘vaccination’ is the term generally accepted for ‘immunisation’, variolation can be the word designating such a technique. The second period of the history of immunisation began, in 1880, with the studies of Pasteur and his collaborators. A great number of bacterial vaccines were developed: dead, live but attenuated or only parts of pathogens. The viruses were produced in animals, then in eggs and at last, in tissue cultures. Second generation vaccines appeared with genetic engineering: recombinant vaccines, vector vaccines, nucleic acids vaccines, and markers vaccines, among others. These novel technologies can permit the development of new ones and improve the quality of the vaccines already existing.  相似文献   

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