Evaluation of serological tests for detecting tick-borne encephalitis virus (TBEV) antibodies in animals

Tick-borne encephalitis (TBE) in animals is not well understood yet. TBE virus (TBEV) serology in several host species could be valuable for epidemiological analyses in the field as well as for the detection of clinical cases. However, performance and suitability of the available test systems are not well assessed. Therefore, we evaluated two commercial TBEV-ELISA kits in a pilot study and compared them for their suitability in veterinary applications. For this purpose, we tested 163 field collected goat sera and evaluated the results by serum neutralization test (SNT) as "gold standard". Twenty-eight SNT positive sera (17.2%) were detected. The best suited ELISA kit was used for determination of a species-specific cutoff for horses, cattle, sheep, goats, pigs, mice, dogs, rabbits and monkeys with defined sera from animals without known or with improbable contact to TBEV. The level of non-specific ELISA results does not only differ between animal species but may also be influenced by the age of the tested animals. The number of sera which tested false positive by ELISA was higher in older than in young sheep. In order to obtain defined polyclonal sera as references, two dogs, cattle, goats, sheep, rabbits and pigs each, as well as one horse and 90 mice were immunized four times with a commercially available TBEV vaccine. In conclusion, our results demonstrated that commercial TBEV-ELISA kits are suitable for application in veterinary medicine for both, verification of clinical TBE cases and epidemiological screening. However, positive ELISA results should be verified by SNT. Only a very low number of false negative ELISA-results were found.     

捻转血矛线虫Hc38基因DNA疫苗对绵羊免疫保护性效果评价

为了研究基因疫苗对绵羊的免疫保护效果,本研究构建了捻转血矛线虫(H.contortus)Hc38基因DNA疫苗.将H.contortus Hc38基因保守结构域克隆到真核表达载体pcDNA3.1中,免疫鼠8d后用RT-PCR检测到该疫苗在鼠肌肉组织中进行了转录.将纯化的DNA疫苗免疫绵羊后,用western blot和ELISA方法检测疫苗在绵羊体内的翻译和诱导IgG的产生.二免后2周用10 000条H.contortus第3期幼虫攻击实验动物,检测绵羊粪便虫卵排出、成虫数量等免疫保护性指标.该H.contortus Hc38 DNA疫苗与对照组比较,免疫组绵羊排出虫卵减少66.6%、成虫减少33.1%.特别值得注意的是免疫组的静脉注射方式产生抗体最高,相应羊的虫卵数和成虫数低.本实验证明Hc38基因DNA疫苗对绵羊虫卵及成虫发育具有明显的抑制作用.     

Comparative study of the pharmacokinetics of alfentanil in rabbits, sheep, and dogs

The central arterial pharmacokinetics of alfentanil, a short-acting opioid agonist, were studied in rabbits, sheep, and dogs after short-duration infusion of the drug. Alfentanil was infused until a set end point (high-amplitude, slow-wave activity on the EEG) was reached. This required a larger alfentanil dose and a higher alfentanil arterial concentration in sheep, compared with rabbits and dogs. The plasma concentration-time data for each animal were fitted, using nonlinear regression, and in all animals, were best described by use of a triexponential function. In this study, differences in the disposition kinetics of alfentanil among the 3 species were found for only distribution clearance and initial distribution half-life. In dogs, compared with rabbits and sheep, the first distribution half-life was longer, probably because of pronounced drug-induced bradycardia (mean +/- SD, 48 +/- 21 beats/min). Distribution clearance was faster in sheep, compared with dogs, also probably because of better blood flow in sheep. Elimination half-life was similar in all species (rabbits, 62.4 +/- 11.3 minutes; sheep, 65.1 +/- 27.1 minutes; dogs, 58.3 +/- 10.3 minutes). This rapid half-life resulted from a small steady-state volume of distribution (rabbits, 908.3 +/- 269.0 ml/kg; sheep, 720.0 +/- 306.7 ml/kg; dogs, 597.7 +/- 290.2 ml/kg) and rapid systemic clearance (rabbits, 19.4 +/- 5.3 ml/min/kg; sheep, 13.3 +/- 3.0 ml/min/kg; dogs, 18.7 +/- 7.5 ml/min/kg). On the basis of these pharmacokinetic variables, alfentanil should have short duration of action in rabbits, sheep, and dogs. This may be beneficial in veterinary practice where rapid recovery would be expected after bolus administration for short procedures or after infusion for longer procedures.     

Antioxidant systems and lymphocyte proliferation in the horse,sheep and dog

To better define the species-specific antioxidant systems and to ascertain the influence of the intracellular redox status on the immune system of different animal species, we determined lymphocyte glutathione peroxidase (GSHPx) activity, plasmatic glutathione levels (GSH) and the effect of H2O2 on the responsiveness of lymphocytes to proliferative stimuli. Among the three species considered, sheep presented the lowest plasmatic GSH and the highest lymphocyte GSHPx activity. On the contrary, dogs showed an inverted pattern (high GSH - low GSHPx). Horses displayed intermediate values for both parameters analysed. The effect of H2O2 on the proliferative capacity of lymphocytes was the same for all three species; the 200 microM dose in particular was strongly inhibiting. Each species, however, showed different rates of inhibition: sheep exhibited the highest sensitivity to the antiproliferative effect of H2O2. Our results confirmed that high H2O2 concentrations (200 microM) are noxious for the cellular functions of all animals; however this effect is mediated by a rigorously species-specific relationship between the intracellular reactive oxygen species (ROS) and the molecular systems involved in cell proliferation.     

Autoimmune orchitis in two related dogs

The testes of three dogs which suffered spermatogenic arrest were examined by indirect immunofluorescence tests. Two of these dogs (a father and son) had previously been shown to have focal inflammatory lesions in the testes. Autoantibodies directed against sperm tails were present in the sera of these dogs, but not in the third dog which had a non-inflammatory testicular degeneration. The findings are compared with those in other animals and man.     

Evaluation of the comparative efficacy of selamectin against flea (Ctenocephalides felis felis) infestations on dogs and cats in simulated home environments

The comparative efficacy of monthly administration of selamectin or lufenuron against Ctenocephalides felis felis on dogs and cats was evaluated over a 5-month period in flea-infested environments. Twenty-four dogs and 32 cats were randomly allocated to receiving a topical treatment with selamectin or an oral administration of tablets containing lufenuron/milbemycin oxime (for dogs) or lufenuron only (for cats). Each product was administered in accordance with the manufacturer's label recommendations. Eight dogs and four cats served as untreated sentinels. Treatments were administered on days 0, 30, 60, 90, and 120. Each animal received an application of 100 fleas on days -28 and -21, and then weekly applications of 20 fleas from days 91 through 147. Flea comb counts were performed on day -6, and every 2 weeks after day 0. From day 29 (dogs) or day 44 (cats) to day 150, geometric mean flea counts for selamectin were < or =0.4. Mean flea counts for animals assigned to treatment with selamectin were significantly lower (P=0.0001) than for animals assigned to treatment with lufenuron at all assessments after day 0.     

Single immunization with an inactivated vaccine protects sheep from Schmallenberg virus infection

The arthropod-borne Schmallenberg virus (SBV), family Orthobunyaviridae, emerged in Europe in 2011. SBV is associated with a mild disease in adult ruminants but fetal malformation after an infection during a critical phase of pregnancy. A number of inactivated vaccines have been developed; their efficacy after two injections was demonstrated. To make the vaccination of sheep more efficient and economic the effect of a single immunization with one of these vaccines was investigated in the present study. Five vaccinated sheep and five additional control sheep were inoculated with SBV three weeks after vaccination and the results of a competitive ELISA, a standard microneutralization test and an SBV-specific real-time RT-PCR confirmed vaccine efficacy by demonstrating complete inhibition of viral replication in immunized animals.     

Prevalence of leptospira species among farmed and domestic animals in Greece

A total of 1527 serum samples from pigs, goats, sheep, cattle and dogs in Greece were examined by the microscopic agglutination test and 11-8 per cent of them had antibodies against one or more Leptospira serovars at titres of 1/100 or more. The predominant serovar affecting farm animal species was Bratislava, and Copenhageni was common among dogs and the second most important serovar when all animals were considered together. Another prevalent serovar was Australis, but antibodies to Pomona were detected only in goats and cattle.     

Leptospira interrogans infection in domestic and wild animals in Fiji

Clinical and serological evidence has indicated that human leptospirosis in Fiji is an important disease, and the prevalence of antibody is exceptionally high. A serological survey of the rural population showed that only 12% of the people studied did not have complement fixing (CF) leptospiral antibody. As the origin of this infection could not be explained by the known distribution of leptospiral infection in domestic and wild animals, a serological survey using the complement fixation test (CFT) was undertaken as the first stage of an epidemiological investigation into human and animal leptospirosis. Sera from domestic and wild animals were tested for CF antibody to 12 leptospiral serovars, namely: pomona, copenhageni, grippotyphosa, hardjo, ballum, tarassovi, canicola, australis, bratislava, autumnalis, pyrogenes and bataviae. Antibody was detected in 27.5% of 480 cattle, 17.1% of 70 sheep, 10.3% of 252 goats, 10.0% of 480 pigs, 57.0% of 100 dogs, 55.8% of 34 rats (Rattus rattus, R. frugivorus, R. exulans and R. norvegicus), 53.1% of 32 mongooses (Herpestes auropunctatus) and 40.0% of 10 mice (species unknown.) Cross-reactivity precluded the identification of infecting serogroups with the exception of pomona in pigs and icterohaemorrhagiae, ballum and australis in dogs. Infection of dogs with a serovar of the australis serogroup may explain the predominance of serological reactions to bratislava in man. The survey revealed a significant level of leptospiral antibody in the animal populations of Fiji and indicated that cattle, dogs, rats, mongooses and mice are probably the most important maintenance hosts. Consequently, further investigation will concentrate on the attempted isolation of leptospires from these species.     

Gonadal function, sexual behavior, feedlot performance, and carcass traits of ram lambs actively immunized against GnRH

The effect of active immunization against GnRH on production, carcass, and behavioral traits was examined in ram lambs fed to a uniform slaughter weight. Lambs (initial BW = 32.6+/-1 kg) were stratified by BW and assigned at random to one of four treatment groups (n = 12 lambs/group). Lambs were untreated, castrated, or actively immunized against GnRH using a GnRH-keyhole limpet hemocyanin conjugate (1 mg) emulsified with either Freund's complete adjuvant (FCA) or another oil-based adjuvant (ISA). Animals were housed individually and slaughtered at 58 kg BW. Immunoneutralization of GnRH reduced (P < .05) testes weight and the concentration of testosterone in serum at slaughter. Suppression of testicular size and function was most clearly evident in animals immunized using FCA. Final anti-GnRH titer was also highest in lambs immunized using FCA. Several measures of sexual behavior (frequency of mounts and ejaculations) were also reduced (P < .05) in animals immunized using FCA. The duration of the feeding period was greater (P < .05) for castrated lambs than for untreated lambs, and intermediate feeding periods were required for FCA and ISA lambs. Average daily gain was greater (P < .05) in untreated than in castrated, FCA, or ISA lambs. Similarly, feed efficiency for untreated lambs was greater (P < .05) than for castrated, FCA, or ISA lambs, but feed efficiency did not differ among castrated, FCA, or ISA lambs. Longissimus muscle area, lean and bone maturity, overall quality, muscling score, flank streaking, and color of fat did not differ among treatments. Intact, FCA, and ISA lambs had more (P < .05) desirable yield grades, less (P < .05) backfat, and less (P < .05) marbling than castrated lambs. In summary, immunization against GnRH decreased testicular weight and reduced (P < .05) feedlot performance and sexual behavior to levels comparable to those of castrated males. Partitioning of nutrients for growth and deposition of fat, however, seems to differ among immunologically castrated and physically castrated lambs. This difference in nutrient partitioning may be due to residual testicular activity in immunized lambs.     

Plasma bile acid elevation following CCI4 induced liver damage in dogs, sheep, calves and ponies.

Plasma bile acid concentration was determined in normal dogs,sheep, calves and ponies for three days before and six days after liver damage, induced by carbon tetrachloride. In all species, a significant increase in plasma bile acid concentration was associated with a concomitant significant increase in plasma sorbitol dehydrogenase and transferase activity. Plasma bilirubin also significantly increased in all animals except the dogs. Results suggested that plasma bile acid levels could be used to test liver function in domestic animals.     

Clinical Use of Testicular Fine Needle Aspiration Cytology in Oligozoospermic and Azoospermic Dogs

Clinical investigation of canine testicular function is complicated by the difficulty in the evaluation of seminiferous tubules. Until recently, testicular biopsy was the only diagnostic option for dogs with persistent oligo/azoospermia. In human andrology, testicular fine needle aspiration (TFNA) is currently considered a useful method in the evaluation of azoospermia and severe oligozoospermia, and has long replaced classical biopsy to evaluate spermatogenesis. In order to verify its diagnostic efficacy for the clinical approach to canine oligo- or azoospermia, TFNA was performed in seven adult (two oligozoospermic and five azoospermic) dogs. After sedation, a fine (21–23 gauge) butterfly needle connected to a 50-ml syringe was inserted into each testicle; strong suction was applied and the aspirated fluid squirted on a glass slide, smeared out, air-dried and stained with a modified May–Grunwald–Giemsa. Under light microscopy, Sertoli cells (all those found in each investigated field) and spermatogenic cells (n = 100) were counted on each smear in order to differentiate spermatogonia, primary spermatocytes, secondary spermatocytes, early spermatids, late spermatids and spermatozoa, and calculate their relative percentages. Cytological analysis showed the following testicular pictures: normal spermatogenesis (compatible with obstruction of the seminal ducts), hypospermatogenesis, maturative disturbances and Sertoli cell-only syndrome. Two dogs with an obstructive lesion were treated with corticosteroids; one of them recovered and sired two litters of puppies.     

Determination of prevalence and risk factors of infection with Babesia in small ruminants from Greece by polymerase chain reaction amplification

A total of 124 blood samples were collected from 92 sheep and 32 goats from 21 randomly selected herds located in two regions of Greece. Data on the characteristics of the animals (species, gender, age, tick burden, presence of haemoglobinuria, prior treatment for babesiosis) and the herd (location, size, species of animals, dogs associated with the herds, tick burden of dogs associated with the herds) were collected through questionnaires. Nineteen animals (15%) produced the DNA fragment specific for Babesia of which 16 were sheep and three were goats. Nucleotide sequence of PCR products revealed 100% homology with Babesia ovis 18S rRNA gene. Nine farms (43%) were found positive for B. ovis. The percentage of positive animals in each farm varied between 10 and 61%. The relative risk of the presence of ticks in sheep and goats (p<0.01) and farm dogs (p<0.01) for PCR-positive results for B. ovis in sheep and goats was found 6.63 and 4.14, respectively.     

Changes in plasma testosterone and testicular transferrin concentration, testicular histology and semen quality after treatment of testosterone-depot plus PMSG to 3 dogs with asthenozoospermia

Three dogs diagnosed as having asthenozoospermia were given three intramuscular injections of 50 mg testosterone(T)-depot plus 250 IU pregnant mare serum gonadotropin (PMSG) at 2-week intervals, and their plasma T and testicular transferrin (Tf) concentrations, testicular histology, and semen quality were examined during the period of hormone therapy. Plasma T concentrations temporarily increased, and there was a slight improvement in spermatogenesis. Increased Tf concentrations suggested that Sertoli cell function in all three dogs was promoted by hormone treatment. The results showed that semen quality, especially the percentages of motile sperm and abnormal sperm, were improved between 1 and 5 weeks after the start of T-depot plus PMSG treatment.     

ELISA检测兰州不同动物粪便中轮状病毒抗原及临床意义

为探讨动物轮状病毒检测的临床价值及本地轮状病毒在不同动物中的流行情况,本研究以秋冬季腹泻的动物为研究对象进行采样,应用轮状病毒单克隆抗体检测其抗原的方法,检测粪便中的轮状病毒。在进行牛、羊、犬粪便轮状病毒检测中发现犬的阳性率最高,其次是牛和羊。表明本地的轮状病毒感染主要集中在幼犬中。本试验为今后动物轮状病毒在临床应用中的检测及动物轮状病毒检测试剂盒的研制等作以参考。     

Distemper vaccination of farmed fur animals in Finland

The most important farmed fur animal species in Finland are the American mink (Mustela vison), blue fox (Alopex lagopus), silver fox (Vulpes vulpes) and raccoon dog (Nyctereutes procyonoides); all are susceptible to canine distemper. The only distemper vaccines currently available are for mink, although they also have been used for fox and raccoon dogs in emergency situations. The efficacy in eliciting neutralizing antibodies and the safety of three mink-distemper vaccines were studied under field conditions with mink and silver fox. Two of the vaccines were also studied with raccoon dogs and blue fox. All three vaccines elicited a satisfactory antibody response in mink, whereas the response varied in the other species. No side effects were observed in any species tested. One of the vaccines was safe and immunogenic in all four species.     

Effect of recombinant canine distemper vaccine on antibody titers in previously vaccinated dogs

Two canine distemper virus (CDV) vaccine types are currently commercially available: modified-live virus (MLV) vaccines and a canarypox recombinant CDV (rCDV) vaccine (Recombitek, Merial). This study compared the ability of the rCDV vaccine and MLV vaccines to significantly enhance (boost) the antibody response of previously immunized adult and juvenile dogs. A significant (fourfold or greater) increase in titer occurred in significantly more dogs revaccinated with Recombitek C-4 or Recombitek C-6 than with the MLV-CDV vaccines. This study demonstrates that Recombitek, the only vaccine for dogs containing rCDV, is more likely to significantly boost the CDV antibody response in previously vaccinated dogs than are the MLV-CDV vaccines. Because rCDV vaccine can boost the antibody titer of dogs previously vaccinated with an MLV vaccine, it can and should be used when core vaccines are readministered.     

我国牛羊弓形虫感染情况及影响因素研究进展

弓形虫几乎可以感染所有的温血动物,是一种十分重要的人兽共患原虫病病原。牛羊弓形虫感染不仅影响其自身的发育和繁殖,对畜牧业发展造成一定的经济损失,更重要的是感染弓形虫的牛羊肉和奶可成为人类健康和生命安全的潜在威胁。牛羊弓形虫感染受多种因素(年龄、品种、养殖场管理及犬、猫和鼠的存在等)的影响,不同地区牛羊弓形虫感染的风险因素不尽相同。基于此,论文对弓形虫感染的检测方法、我国不同地区牛羊弓形虫的感染情况及影响弓形虫感染的因素进行综述,旨在为相应地区牛和羊的饲养管理及保障其奶和肉产品的安全供给提供参考。     

Morphological study of the effects of the GnRH superagonist deslorelin on the canine testis and prostate gland

The present study is part of a programme of research designed to evaluate the efficacy of the GnRH superagonist,deslorelin (D-Trp6-Pro9-des-Gly10-LHRH ethylamide), as a contraceptive for male dogs. Adult dogs were assigned to a completely randomized design comprising six groups of four animals. Each dog in the control group received a blank implant (placebo) and each dog in the other five groups received a 6 mg deslorelin implant. One group of deslorelin treated dogs was sacrificed on each of days 16, 26, 41, 101 and 620, and testicular and prostate tissues were collected for study by light and electron microscopy. On days 16 and 26 after implantation, we observed partial disruption of the seminiferous tubules, with early spermatids shed into the lumen. On days 41 and 101 after implantation, 90–100% of the seminiferous tubules were atrophic and aspermatogenic.On day 101 after implantation, 99% of all sections showed atrophy of the epithelium and shrinkage of epithelial height in the ductus epididymides. On days 41 and 101 after implantation, prostate tissue showed complete atrophy of the glandular epithelium (100% of sections) and an apparent increase in the relative proportion of connective tissue. At the electron microscopic level, in dogs treated with deslorelin for 41 and 101 days, the Sertoli cells were smaller and their nucleoli appeared smaller than in the control dogs. The nucleoli of the Leydig cells were atrophied and prostate glandular epithelium showed reduced epithelial height, a trophy of the nucleolus and an absence of secretory granules.Tissues collected during the recovery phase revealed a complete recovery of spermatogenesis. In conclusion, slow release implants containing deslorelin induce a striking a trophy of the testes and prostate gland by 26 days after implantation, explaining the previously reported loss of ejaculate and arrest of sperm output. At histological level,the entire process appears to be completely reversible, in accordance with data on endocrine variables and semen production.     

Effect of the probiotic Enterococcus faecium SF68 on presence of diarrhea in cats and dogs housed in an animal shelter

Background: Beneficial effects of probiotics have never been analyzed in an animal shelter. Hypothesis: Dogs and cats housed in an animal shelter and administered a probiotic are less likely to have diarrhea of ≥2 days duration than untreated controls. Animals: Two hundred and seventeen cats and 182 dogs. Methods: Double blinded and placebo controlled. Shelter dogs and cats were housed in 2 separate rooms for each species. For 4 weeks, animals in 1 room for each species was fed Enterococcus faecium SF68 while animals in the other room were fed a placebo. After a 1‐week washout period, the treatments by room were switched and the study continued an additional 4 weeks. A standardized fecal score system was applied to feces from each animal every day by a blinded individual. Feces of animals with and without diarrhea were evaluated for enteric parasites. Data were analyzed by a generalized linear mixed model using a binomial distribution with treatment being a fixed effect and the room being a random effect. Results: The percentage of cats with diarrhea ≥2 days was significantly lower (P= .0297) in the probiotic group (7.4%) when compared with the placebo group (20.7%). Statistical differences between groups of dogs were not detected but diarrhea was uncommon in both groups of dogs during the study. Conclusion and Clinical Importance: Cats fed SF68 had fewer episodes of diarrhea of ≥2 days when compared with controls suggests the probiotic may have beneficial effects on the gastrointestinal tract.