Herd-specific and age-specific seroprevalence of Neospora caninum in 14 British dairy herds.

All the cattle in 14 dairy herds in England were tested for Neospora caninum-specific antibodies with a commercial ELISA. Three of the herds had had sporadic abortions, eight had had endemic abortions and three had had epidemic abortions associated with N caninum before the study. Of 4295 cattle tested, 17.1 per cent were seropositive and the herd-specific prevalence ranged from 7.3 per cent to 44.8 per cent. No significant effect of either herd size (P = 0.988), endemic (P = 0.869) or epidemic (P = 0.138) patterns of abortion on herd-specific prevalence was found by using logistic regression analysis. There was no evidence in any herd of a significant increase in prevalence with age; the prevalence in seven-to 12-month-old cattle was not significantly different (P > 0.400) from the prevalence in older cattle, except that there was a significantly lower prevalence (P = 0.017) in 13-to 24-month-old cattle. The results of this study are consistent with vertical transmission being the major route of N caninum transmission in these herds.     

Foot-and-mouth disease vaccination: a multifactorial study of the influence of antigen dose and potentially competitive immunogens on the response of cattle of different ages

Groups of 68 and 66 cattle aged 12 and 24 months respectively were each subdivided into 16 groups and inoculated with foot-and-mouth disease vaccines containing O1 Campos, A24 Cruzeiro and C3 Pando virus strains. The 140S antigen mass of the O1 and A24 valencies was varied while that of C3 was held constant. Multifactorial comparisons between the 21 day serum neutralising antibody titres showed that over most of the range there was a linear log dose response relationship. Doubling the antigen dose increased the serum antibody titres against both A24 Cruzeiro and O1 Campos by approximately 0.15 log10. The A24 antigen was about 30 times more immunogenic than the O1 with C3 intermediate between the two. At high antigen doses the responses flattened but the level at which this occurred depended on the immunogen administered. No difference could be demonstrated between the responses of 12- and 24-month-old cattle and there was no evidence of competitive inhibition or enhancement between the virus strains included in the vaccines.     

Undifferentiated bovine respiratory disease (shipping fever): Is it communicable?

A study was conducted on 6–8-month old calves entering 2-research facility feedlots in 1983–1985, to examine if the occurrence of undifferentiated bovine respiratory disease (BRD) clustered within pens. For the purposes of analysis, 12 different groups of cattle were formed based on the source of cattle within year and/or year of arrival.The morbidity rates of BRD ranged from 5.7 to 64% and varied significantly from group to group (i.e., source to source) within year and from year to year. In all groups except one, the secondary attack (morbidity) rates were lower than the morbidity rates.An algorithm to examine for extra-binomial variation was used to formally examine for pen effects (clustering of disease within pen). In all models, a simple binomial model was sufficient to describe the data, i.e., the usual binomial parameter was estimated to describe the mean level of BRD by group, no additional parameter estimates were required to describe pen effects within group.Thus, although BRD has important pathogens as part of its sufficient causes, there is no evidence that clinical disease in one individual increases the risk of disease for other cattle in the same pen.     

Effects of Castration at 6 Months Old on Growth Performance,Testosterone and Growth Hormone Levels in Blood of Yanbian Cattle

In order to study the effect of castration at 6 months old on growth performance and blood hormones of Yanbian cattle at 6 to 18 months of age, 20 Yanbian cattle that were 6 months old with similar body weight and body size indexes were randomly divided into 2 groups. The cattle in test group was castrated at 6 months old,and that in control group did not do any treatment,and the test period was 12 months. At the 12th of 6,8,10,12,14,16 and 18 months old,the body weight and body size indexes were measured,and the fasting blood sample were collected the day before 12th to detect the serum testosterone and growth hormone. The results showed that the body weight of the test group was lower than that of the control group,and there was a significant difference at 8 months old (P < 0.05). The body height,body length and chest circumference of the test group were lower than that of control group(P>0.05),and the increase of body height of test group was significantly lower than that of control group at the age of 6 to 8 months old (P < 0.05),while that was significant higher than control group at 12 to 14 months old (P < 0.05). The level of serum testosterone in the test group was extremely significantly or significantly lower than that in the control group after castration (P < 0.01;P < 0.05), and the level of serum growth hormone in Yanbian cattle was significantly lower than that in the control group at 8 months old (P < 0.05). In summary,the castration at 6 months old could reduce the growth of body weight,serum testosterone and growth hormone levels of Yanbian cattle,but had little effect on the body size.     

6月龄去势对延边黄牛生长性能、血液睾酮及生长激素水平的影响

为研究6月龄去势对延边黄牛生长性能及血液激素的影响,试验选用20头6月龄体重、体况相近的延边黄牛,随机分成2组,每组10头,试验组黄牛6月龄去势,对照组不去势,试验期12个月。试验期间在试验牛6、8、10、12、14、16及18月龄的当月12号称重并测量体尺,每次称重前一天早上空腹经颈静脉采血,检测血清睾酮和生长激素的含量。结果显示,试验期间试验组黄牛去势后体重均低于对照组,其中8月龄时差异显著（P < 0.05）;试验组延边黄牛体高、胸围、体斜长均低于对照组,但差异均不显著（P > 0.05）,6~8月龄时,试验组去势黄牛体高的增长显著低于对照组（P < 0.05）,12~14月龄时,试验组显著高于对照组（P < 0.05）,其他月龄间两组差异不显著（P > 0.05）。试验组黄牛去势后血清睾酮水平极显著或显著低于对照组（P < 0.01;P < 0.05）,试验组黄牛血液生长激素水平低于对照组,其中8月龄时差异显著（P < 0.05）。综上所述,6月龄去势能够降低延边黄牛体重的增长,但对体尺影响不大,且能降低延边黄牛血清睾酮及生长激素水平。     

Ability of adults of Amblyomma hebraeum (Acarina: Ixodidae) to feed repeatedly on sheep and cattle

Adult Amblyomma hebraeum ticks were exposed at 14-day intervals on five sheep on 46 occasions and on three cattle on 15 occasions to determine the effects of repeated feeding. The engorged weight and percentage of ticks which fed successfully on sheep declined significantly at first but subsequently they increased. On cattle there was no progressive decline in engorged weight, although the percentage which fed successfully declined significantly and was lower than that for sheep. This decline was attributed to increased grooming by cattle and was the only apparent mechanism by which resistance was expressed.     

Comparison of the specificty of human and bovine tuberculin PPD for testing cattle. 1--Republic of Ireland.

A tuberculin testing trial in cattle was carried out in the Republic of Ireland to compare the specificity for bovine tuberculosis of a human purified protein derivative (PPD) tuberculin (Weybridge) with that of a bovine PPD (Rotterdam), and to determine whether discrimination between specific and non-specific reactions to mammalian tuberculin is better with doses of tuberculins smaller than those traditonally used for testing cattle. Tests were carried out in 510 cattle, 395 of which were shown by post mortem examination to be tuberculous and 115 non-tuberculous. Three dilutions at five-fold intervals of both mammalian tuberculins were used together with two dose levels of avian tuberculin PPD (Weybridge), and all reactions were measured both by increase in skin fold thickness and by diameter of induration. In the environment of this trial, the bovine PPD was shown to be more specific for bovine tuberculosis than the human PPD, and particularly in differentiating from "skin tuberculosis". There was no indication of greater specificity at lower doses of tuberculin. Measurement of induration diameter proved a satisfactory alternative method of reading tuberculin reactions in cattle under field conditions.     

The application of moxidectin formulations for control of the cattle tick (Boophilus microplus) under Queensland field conditions

Objective To assess the control of the cattle tick (Boophilus microplus) and the performance of commercial cattle treated with the macrocylic lactone endectocide, moxidectin, formulated either as an injection or as a pour-on. Design Groups of 10–12 tick infested cattle were treated with moxidectin injection, moxidectin pour-on or remained untreated (28-day trials) or were treated with deltamethrinethion as a dip (140-day trials). The cattle were exposed to natural tick challenge under field conditions. Procedure Tick numbers on trial cattle were recorded in each trial before the initial treatment and in the 28-day trials at 7, 14, 21 and 28 days or in the 140-day trials, at 28-day intervals before each of the treatments and at the final inspection. Body weights of the cattle were also recorded prior to the initial treatment and at the termination of each trial. Cattle were observed on the day of each treatment and at each inspection for evidence of any reactions to treatment. Results 28-day trials: Significant reductions in tick counts were recorded in both treatment groups when compared with cattle in the untreated group. Weight advantage was recorded in the moxidectin treated groups. 140-day trials: All three treatments resulted in zero or low tick counts at each inspection with the exception of the pour-on treatment at week 8 in one trial and week 9 in the other trial. Additional weight gain was recorded for both the moxidectin treated groups, relative to the deltamethrin-ethion dip groups, but was significant only for the pour-on groups. There was no evidence of any local or systemic adverse reaction in any treated cattle in any trial. Conclusion Good to excellent control of the cattle tick (Boophilus microplus) was demonstrated with the moxidectin formulations in all trials, the injection being particularly effective. An improved performance was recorded in all trials in cattle treated with both moxidectin formulations when compared with the untreated cattle and with cattle treated with the deltamethrin-ethion dip. There was no evidence of any local or systemic adverse reaction to treatment with either moxidectin formulation.     

Measurement of vitamin B12 in the livers and sera of sheep and cattle and an investigation of factors influencing serum vitamin B12 levels in sheep

Modifications of a radioassay method for the analysis of vitamin B12 using chicken serum as the binder are described. This obviates the need to use individual serum blanks to correct for non-specific binding in vitamin B12 assays of the sera and livers of sheep and cattle. Samples with high vitamin B12 levels can be diluted prior to assay without loss of linearity. Recoveries of added cyanocobalamin or hydroxocobalamin were better than 95% and results correlated significantly with those obtained using a microbiological assay (Poteriochromonas malhamensis). Sera and liver samples stored for four weeks at temperatures ranging from -20 degrees to 22 degrees showed no change in vitamin B12 levels. Withholding food from sheep for 44 hours led to a marked increase in serum vitamin B12. This effect was also evident in sheep eating a limited amount of cut grass. In sheep at pasture there was no evidence of a diurnal variation in serum vitamin B12 levels. Serum vitamin B12 levels in sheep at pasture were shown to be an unreliable indicator of liver vitamin B12.     

Radioactive gold-198 seeds for the treatment of squamous cell carcinoma in the eyelid of a cat

A 19-year-old, speyed, domestic short-hair cat was presented with an eyelid tumour of 3 months duration. Ophthalmic examination revealed a large, raised, ulcerated and bleeding mass affecting the left lower eyelid. The mass was 12 mm x 10 mm in size, extended to the medial canthus and had eroded 10 mm of eyelid margin. Mandibular lymph nodes were not palpably enlarged. A diagnosis of squamous cell carcinoma was confirmed by histologic examination. Due to involvement of more than half the lower eyelid, it was decided that treatment with radioactive gold-198 seeds was appropriate. Nine radioactive gold-198 seeds were implanted, delivering a minimum tumour dose of 65 Gy. Three weeks postoperatively the mass had resolved, with only a small scab remaining. After a further 3 weeks, there was no evidence of the eyelid tumour. Although approximately 7 mm of eyelid margin was absent, this did not cause any clinical signs other than mild conjunctivitis. There was no evidence of the tumour 10 months postoperatively, when the cat was euthanased for unrelated disease.     

Isolation of Leptospira hardjo from kidneys of Ontario cattle at slaughter.

Kidneys from 117 cattle from 110 Ontario farms were examined at slaughter for leptospires. Leptospira hardjo (hardjo-bovis A) was isolated from 11 kidneys and L. kennewicki from one. The isolations were all made (12/89, 13.5%) from beef cattle from feedlots, no isolates being obtained from dairy or beef cattle from extensive farms (0/28). Isolations were only made from cattle with antibody titers (greater than or equal to 20) against the serovars recovered. Isolation was more sensitive than immunofluorescence in identifying leptospira, particularly in animals with low antibody titers against L. hardjo. Leptospira were isolated from two kidneys with multiple gross lesions of focal nephritis, but there was no correlation between the presence of scanty kidney lesions and isolations of leptospira. Leptospira hardjo infection appears to be common in Ontario feedlot cattle.     

Antimicrobial susceptibility of pathogenic Escherichia coli isolated from sick cattle and pigs in Japan

We examined the 12 antimicrobial susceptibilities of 175 E. coli isolates from sick cattle and pigs by an agar dilution method. Resistance was found in 78.3% of isolates for oxytetracycline, 70.3% of isolates for dihydrostreptomycin, and 49.1% of isolates for ampicillin. When compared with healthy animals reported by Kijima-Tanaka et al., resistance rates for 11 antimicrobial agents were higher in sick cattle than in healthy cattle, and resistance rates for all antimicrobial agents were higher in sick pigs than in healthy pigs. Comparing cattle and pigs, resistance rates to colistin was higher in porcine isolates than in bovine isolates, but was lower in porcine isolates than in bovine isolates for cefazolin. With regard to the association of virulence factors, higher resistance rates to colistin and enrofloxacin were observed in STEC (61 strains) than in non-STEC (57 strains) among porcine isolates, while there were no significant differences in bovine isolates. In conclusion, these results can be considered helpful for adequate selection and prudent use of antimicrobial agents for several types of colibacillosis.     

瑞士褐牛蜘蛛腿综合征致病位点检测方法的建立

牛蜘蛛腿综合征（Arachnomelia Syndrome,AS）是一种常染色体隐性遗传病,现主要见于德系西门塔尔牛和欧洲瑞士褐牛。患病犊牛先天骨骼系统严重畸形,出生即死亡或出生不久死亡。已证实瑞士褐牛蜘蛛腿综合征是由编码亚硫酸盐氧化酶的基因SUOX外显子4上一个单碱基插入突变c.363-364insG所致。本研究首次建立了瑞士褐牛蜘蛛腿综合征致病基因突变位点分子筛查的方法：荧光引物PCR产物电泳法和PCR产物直接测序法。使用荧光引物PCR产物电泳法对10个品种187头牛样本进行该突变位点的基因型分型,没有发现携带该致病基因的个体。荧光引物PCR产物电泳法判定基因型快速可靠,实验成本较低,适合大规模群体的检测。由于我国曾多次进口瑞士褐牛遗传物质,可能将该致病基因引入本地牛群体。因此对我国相关牛群开展AS隐性不利基因的筛查是必要的,尤其是针对种公牛进行筛查,可避免该致病基因在群体的传播造成重大经济损失。     

Efficacy trial of an irradiated cattle lungworm vaccine in red deer (Cervus elaphus)

Lungworm (Dictyocaulus sp.) is the parasite of most concern to the New Zealand deer industry. Although lungworm can be controlled by anthelmintics there is an increasing concern over excessive drenching programmes and reliance on chemicals for parasite control. A live irradiated larval vaccine developed for cattle has been available in Europe for the past 40 years but has never been evaluated in red deer in New Zealand. Four groups of red deer and two of cattle were hand reared from birth in parasite-free conditions. The cattle acted as a control group to ensure that the vaccine was still efficacious on arrival in New Zealand. Two groups of deer were vaccinated, and all four groups were challenged with either D. viviparus or deer origin Dictyocaulus, tentatively identified as D. eckerti. The vaccine provided excellent protection to cattle under New Zealand conditions, there was no larval output in the vaccinated cattle and no adults were found in their lungs at necropsy. In red deer, patency was delayed in the vaccinated groups regardless of challenge species and larval output was lower but was not prevented. Adult lungworms were found in the lungs of all deer at necropsy but fewer were recorded in the vaccinated deer. Although Huskvac provided a degree of protection for red deer it was not effective enough to recommend its use.     

Effect of five daily intravenous treatments with oxytetracycline hydrochloride on the carrier status of bovine anaplasmosis.

Intravenous administration of oxytetracycline hydrochloride at the rate of 22 mg/kg daily for 5 days was effective in rendering parasite-free 11 adult cattle that were naturally infected Anaplasma marginale carriers. The treatment did not cause any noticeable distress or side effect. Through 12 posttreatment months, the efficacy of the treatment procedure was evaluated by serologic tests and subinoculation of blood into susceptible splenectomized calves. Results of the rapid card agglutination test were positive for 5 cattle at 2 months after treatment, but negative for all cattle at 4 through 12 months. Complement-fixation titers were variable and transient in posttreatment serologic studies. After subinoculation of blood into splenectomized calves (at 4 and 12 months after chemotherapy), serologic, hematologic, or clinical evidence of infection with A marginale was not seen during a 60-day observation period.     

No evidence for involvement of sheep in the epidemiology of cattle virulent epizootic hemorrhagic disease virus

Epizootic hemorrhagic disease virus (EHDV) is an Orbivirus. While not previously considered as an important disease in cattle, several EHDV serotypes (EHDV-6 and 7) have recently been implicated in disease outbreaks. The involvement of sheep in the epidemiology of EHDV is still not understood. In this study we compared the prevalence of antibodies to EHDV and bluetongue virus (BTV) in sheep to their prevalence in cattle after an outbreak of EHDV that occurred in Israel during 2006. Sixty-six sheep and lambs scattered in seven herds were compared to 114 cows and calves scattered in 13 dairy cattle herds, matched to the sheep herds by location. While antibody prevalence to EHDV was high in cattle (35.2% within the outbreak zone) no evidence of exposure to EHDV was found in sheep (p<0.0001). Antibodies to BTV were apparent in both cattle and sheep though in the former it was significantly higher (63.2%, 16.7% respectively, p<0.0001), suggesting higher exposure of cattle to biting Culicoides midges. Taken together, these results imply that sheep have a negligible role in the epidemiology of EHDV.     

不同品种和年龄牛胆囊的比较组织学研究

通过对八例健康黄牛和健康小牛胆囊的比较组织学观察，我们发现，牛胆囊中以颈部粘膜皱臂明显，体部渐平坦，底部最少。粘膜上皮为单层柱状上皮，内有少量杯关细胞，大部分胆囊可见有淋巴滤泡，但是在血管周围未见淋巴和异染细胞的浸润，证明滤泡的形成与胆囊感洒无关。这种淋巴滤泡在黄牛胆囊中较多，水牛胆囊仅见一例。在黄牛和水牛胆囊中，均有腺体存在，黄牛的腺体明显多于水牛。腺体分为浆液腺、粘液腺和混合腺。老龄牛胆囊中腺     

The minor role of pigs in outbreaks of foot-and-mouth disease of northern Thailand

SUMMARY: A study was undertaken in northern Thailand to examine the involvement of pigs in outbreaks of foot-and-mouth disease (FMD). Data were collected by surveying selected villages, by serological monitoring of pigs and by investigating outbreaks. Fifty-three of 58 villages (91%) surveyed reported that pigs did not develop FMD during the most recent outbreak. The source of 49/60 (82%) outbreaks was attributed to either recent purchases of infected cattle and buffalo or commingling of cattle and buffalo with stock from an infected neighbouring village. One of 60 villages (1.7%) reported that the source was introduced infected pigs. There was no association between the various hypothesised risk factors relating to the management of pigs and the frequency of FMD outbreaks in the survey. The percentage of seropositive pigs during 3 rounds of serological monitoring conducted at 6-monthly intervals in selected villages was 3.5%, 2.6% and 0%, respectively. No clinically affected pigs were observed in 11 outbreak investigations. It was concluded that pigs did not commonly become infected when there were outbreaks of FMD in village cattle and buffalo in northern Thailand. This was probably due to the pig feeding and housing practices employed by villagers that protected pigs from exposure to virus from infected cattle or buffalo, or their products.     

谷氨酸渣对秦川肉牛生长发育和血液生化指标的影响

试验旨在研究添加不同水平的谷氨酸渣对秦川牛肉用新品系（以下简称"秦川肉牛"）生长发育和血液生化指标的影响。选取秦川肉牛18月龄公牛、母牛及8月龄阉牛各12头,按照单因素随机区组设计分成4组,每组9头牛（含3头公牛、3头母牛和3头阉牛）,各组添加不同水平的谷氨酸渣替代日粮中部分豆粕,即对照组（0）、试验Ⅰ组（1.5%）、试验Ⅱ组（3.0%）、试验Ⅲ组（4.5%）。试验期100 d,期间进行采食量和体重测定,试验结束后采集血样进行血液生化指标测定。结果表明：试验Ⅰ、Ⅱ、Ⅲ组肉牛平均日增重（ADG）显著高于对照组（P<0.05）,且试验Ⅱ组显著高于试验Ⅰ组和Ⅲ组（P<0.05）;试验Ⅱ、Ⅲ组肉牛干物质采食量（DMI）显著高于对照组（P<0.05）;试验Ⅱ组肉牛料重比（F/G）也显著低于对照组（P<0.05）。对照组、试验Ⅰ组和试验Ⅱ组肉牛血液碱性磷酸酶含量显著高于试验Ⅲ组（P<0.05）,其余血液生化指标在各组间差异不显著（P>0.05）。肉牛血液碱性磷酸酶含量与平均日增重之间相关性极显著（P<0.01）。综合以上结果,添加3.0%谷氨酸渣替代日粮中部分豆粕可以促进肉牛采食,提高其平均日增重（提高22.62%）,降低料重比（降低10.85%）;日粮中适量添加谷氨酸渣（1.5%~3.0%）显著提高了肉牛血液中碱性磷酸酶活性,该酶活性的高低可能是衡量肉牛生长发育水平的重要指标。     

Effects of farm management practices on cattle grazing behaviour and the potential for transmission of bovine tuberculosis from badgers to cattle

Despite the large body of circumstantial evidence to suggest a link, the means by which bovine tuberculosis is passed from badgers to cattle remains unclear; pasture contamination with the urine, faeces and/or sputum of infectious badgers is believed to be the main route of transmission. Therefore the behaviour of grazing cattle was studied to determine whether they avoided investigating and/or grazing pasture contaminated with badger excreta, and whether different farm management practices enhanced the potential for disease transmission. Active latrines were avoided by most cattle until the sward length in the rest of the field was reduced, after which there was an increasing likelihood that active badger latrines would be grazed. Most of the cattle grazed active badger latrines, but cattle of low rank within the herd grazed latrines more heavily. Farm management practices that reduced the availability of long swards shortened the period of investigative behaviour and greatly enhanced the risk that cattle would graze active badger latrines. Cattle were more likely to graze pasture away from latrines that was contaminated either with badger urine or single faeces. Because bacilli remain viable in the soil for up to 2 years, there is the potential for bacilli to accumulate at active badger latrines, and these could pose a significant risk to cattle, even when the latrine is no longer being used by badgers. Cattle readily grazed the lush sward at disused latrines, during which they could ingest contaminated soil; the amount of soil ingested increases as sward length decreases.