鸽Ⅰ型副粘病毒的RT—PCR套式PCR检测方法的建立

对3个中国广东的鸽Ⅰ型副粘病毒分离株（P4，P5和P7）基因组RNA以反转录－聚合酶链反应法（RT－PCR）扩增了F基因75％的基因区域（343－1673nt），其中毒株P4和P7准确扩增出预期大小明亮的DNA片段，而P5扩增出片段很淡，用该RT－PCR产物作模板以相同引物再作PCR，结果可以扩增出大小与预期一致的明亮条带，此方法可以快速检测鸽Ⅰ型副粘病毒（PPMV－1）。     

鸽Ⅰ型副粘病毒F基因的序列分析

本研究采用RT-PCR方法成功地获得了3个鸽I型副粘病毒广东分离株(P4、P5和P7的F基因片段。经测序表明，基因片段长度均为1290bp；经序列分析发现，毒株P4与NDV标准株La Sota和C30的同源性最高，达到99．4％；而毒P5、P7与La Sota和C30的同源性相对较低，为83％。从建立的系统发育树可看出，毒株P4与NDV标准株La Sota和C30有很近的亲缘关系，而毒株P5、P7与NDV标准株La Sota和C30的亲缘关系相对较远。     

应用反转录—聚合酶链反应检测鸽Ⅰ型副粘病毒的研究

根据鸡新城疫病毒（ＮＤＶ）和鸽副粘病毒Ｆ基因的保守序列，设计合成１对引物ＸＺ９、ＸＺ１０，用反转录－聚合酶链反应（ＲＴ－ＰＣＲ）对３种株鸽Ⅰ型副粘病毒均扩增出与预期大小相符的ＲＴ－ＰＣＲ产物，而对鸡传染性支气管炎病毒、禽传染性喉气管炎病毒、大肠埃希氏菌、禽腺病毒、禽巴氏杆菌扩增结果均为阴性；ＲＴ－ＰＣＲ最低能检出１ｐｇ的鸽Ⅰ型副粘病毒的核酸模板。     

广西猪源I型副粘病毒F基因测序分析

对广西猪源I型副粘病毒F基因测序分析,为今后开展猪源副粘病毒的相关研究提供参考,也为有效防控副粘病毒感染奠定基础。参考GenBank发表的相关禽副粘病毒I型（Avian paramyxovirus serotypeI,APMVx）基因组序列,设计了1对特异性引物,用RT—PCR法分别扩增出病毒各F基因片段,并将目的基因片段回收纯化。测定得F基因的序列结果表明,从猪组织中分离获得1株猪源禽I型副粘病毒,分离株F基因112～117住裂解住点的氨基酸组成为R—R—Q－R—R-F,与强毒株DQ417113、AF458012的裂解位点一致。同源性分析结果表明,分离株与标准强毒株的核苷酸同源性分别为87．5％和87．4％。猪源禽I型副粘病毒分离株为强毒株,属于基因I型是传统型毒株,广西地区禽I型副粘病毒宿主范围呈不断扩大趋势。     

A型产气荚膜梭菌四环素耐药基因的PCR检测

为了检测A型产气荚膜梭菌四环素耐药基因,试验采用Oligo 6.0软件设计tet A(P)、tet B(P)四环素耐药基因的特异性引物,片段大小分别为1 263 bp和1 959 bp,提取A型产气荚膜梭菌质粒DNA,配制PCR反应体系,设置PCR反应条件,用PCR扩增产物进行1%琼脂糖凝胶电泳。结果表明:特异性引物能有效扩增A型产气荚膜梭菌tet A(P)和tet B(P)基因,目的基因大小与预期片段相符。     

胶东地区耐药猪源大肠杆菌I型整合子-基因盒流行状况分析

在胶东地区119株多重耐药大肠杆菌中,共92株菌有I型整合子整合酶基因,检出率达77．31％。92株I型整合子携带大肠杆菌共扩增出7类不同大小的基因盒插入区片段,大小分别为1008bp、1318bp、1586bp、1663bp、1913bp、1945bp、3149bp,其中以大小为1008bp的插入区片段的检出率最高,为31．67％。而检出率最低的为长度为1318bp的基因盒插入区。将基因盒插入区扩增片段的测序结果与Genebank中的相关序列进行比对,得出I型整合子携带的耐药基因盒种类分别为aadA1、aadA2、aadA5、aadA22、aadB、dfrA1、dfrA12、dfrA17、dfrA27、1nuF、cmLA6、aar-3、orff分别编码对相应药物的耐药性。     

鸡痘病毒PCR检测方法的建立及临床应用

根据已发表的鸡痘病毒(fowlpox virus,FPV)4 b核心蛋白基因的核苷酸序列设计合成了(P3,P5)1对引物,通过对影响PCR扩增条件的优化,在不同的退火温度下,直接以病毒液为模板扩增出预期的1 107 bp的片段。特异性检测表明,两对引物对FPV102株、FPV282E4(北京)、大华农鸡痘疫苗毒株、重组鸡痘疫苗病毒及临床病料均能扩增出相应的特异性片段,而用鸡马立克氏病毒、传染性支气管炎病毒,鸽痘病毒及鸡胚成纤维细胞制备的模板进行PCR扩增均为阴性。敏感性检测表明,引物能检测0.195 ng/μL的模板量。用此方法检测50份临床样品,其中的阳性率为92%,用琼脂扩散试验方法检测的阳性率为70%。以上结果表明,该方法可以用于FPV临床样品的检测。     

新城疫病毒F_(48)E_9株P基因的克隆及鉴定

根据NDVP蛋白己知基因序列设计合成了一对引物PU/PL ,利用RT_PCR扩增出了F4 8E9株P基因 12 72bp的片段 ,将该片段克隆到pMD18_TVector上 ,并对所得到的重组质粒进行酶切分析、PCR鉴定 ,结果证明我们得到了这个基因片段的阳性重组子。为了更充分证实所得阳性质粒的可靠性 ,采用Sanger’s双脱氧末端终止法对阳性重组子从 5’端进行核苷酸序列测定 ,获得了F4 8E9株P基因片段 5’端的基因序列 ,利用DNASIS分析软件 ,将F4 8E9株与LaSota株的相应序列进行比较 ,其核苷酸序列同源性为 83 7%。至此 ,我们获得了F4 8E9株P基因的全长克隆     

胶东地区耐药猪源大肠杆菌Ⅰ型整合子-基因盒流行状况分析

在胶东地区119株多重耐药大肠杆菌中,共92株菌有I型整合子整合酶基因,检出率达77.31%。92株I型整合子携带大肠杆菌共扩增出7类不同大小的基因盒插入区片段,大小分别为1008bp、1318bp、1586bp、1663bp、1913bp、1945bp、3149bp,其中以大小为1008bp的插入区片段的检出率最高,为31.67%。而检出率最低的为长度为1318bp的基因盒插入区。将基因盒插入区扩增片段的测序结果与Genebank中的相关序列进行比对,得出Ⅰ型整合子携带的耐药基因盒种类分别为aadA1、aadA2、aadA5、aadA22、aadB、dfrA1、dfrA12、dfrA17、dfrA27、lnuF、cmLA6、aar-3、orfF分别编码对相应药物的耐药性。     

口蹄疫病毒3C蛋白酶的T4噬菌体表面展示

对FMDV3C基因克隆质粒p3C-T进行PCR扩增，获得了口蹄疫病毒3C蛋白酶基因片段，将此片段与T4噬菌体整合质粒pR的EcoR I酶切片段连接，转化E．coli DH5a工程菌，经EcoR I酶切、质粒PCR扩增、插入方向筛选及测序鉴定，成功获得了T4噬菌体重组整合质粒pR-3C。将其转化E．coliE2后，与SOC基因缺失的噬茵体9T4-Z1同源重组，经溶菌酶依赖性筛选，获得了快速溶菌型噬菌体9T4—3C。经噬菌体PCR扩增、SDS-PAGE分析和Western-blot分析，重组噬菌体可展示约26ku的重组蛋白；其大小与预期相符，具有免疫原性。     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

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.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

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.     

Prevalence of gastric lesions in racing Alaskan sled dogs

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.     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

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.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

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.     

Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ

An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.     

Serum biochemical values and mineral element contents of tissues in yaks

Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein     

Avian brood parasitism — a growing research area in behavioral ecology (part Ⅱ)

正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -