Serological responses of cattle inoculated with inactivated trivalent foot-and-mouth disease vaccine at the wildlife-livestock interface of the Kruger National Park, South Africa.

Foot-and-mouth disease (FMD) virus is economically one of the world's most important animal pathogens, which can be responsible for losses in livestock trade, as well as frequent and highly disruptive large-scale epidemics. The control of FMD in southern Africa typically includes vaccination of cattle with a trivalent or bivalent vaccine preparation. The objective of this study was to determine the level and duration of the antibody responses conferred by the current FMD vaccination programme in cattle at the western boundary of the Kruger National Park (KNP) in South Africa. Two hundred and eighty-three cattle from four communal dip tanks were longitudinally sampled after vaccination using an inactivated trivalent FMD vaccine (South African Territories (SAT) 1, SAT 2 and SAT 3). Blood samples were collected fortnightly over four months and antibodies were measured using a liquid-phase blocking ELISA. Only 5%, 43%, and 16% of enrolled cattle had evidence of pre-existing antibody responses to the three SAT viruses at the beginning of the study (≥1.6 log10 titre for SAT 1-3 respectively), which was 7-12 months after the last vaccination campaign. However, 14 days after vaccination this proportion increased to between 66% and 93%, with SAT 2 having the highest proportion. Young animals (<1 year old) tended to have higher predicted baseline antibody levels that peaked by 14 days. Positive serological responses were transient and by 56 days post-vaccination antibody levels begun to decline below the threshold of 1.6 log10 titre. Predicted peak antibody levels only consistently reached 2.0 log10 for SAT 2. Serological responses for SAT 2 tended to be longer, but in most cases the duration of antibody levels was short-lived. More research is necessary to determine the reasons for the limited duration of antibody responses, especially among younger cattle, in order to achieve more effective prophylactic vaccination.

Serological evidence of vaccination and perceptions concerning Foot-and-Mouth Disease control in cattle at the wildlife-livestock interface of the Kruger National Park, South Africa.

Communal livestock farming areas adjoining the Greater Kruger National Park Area within South Africa are part of the Foot-and-mouth disease (FMD) Protection Zone with Vaccination due to the proximity to wildlife reservoirs. FMD and its control affect the productivity of resource-poor farmers who often depend on livestock for their livelihoods. A cross-sectional study was performed with the objectives to evaluate the perceptions of farmers concerning FMD control, estimate the proportion of cattle with presumed protective antibody titres against FMD, as well as the proportion of herds with adequate herd immunity at the wildlife-livestock interface within Mpumalanga Province. One hundred and four farmers were interviewed with 73% (76/104) being cattle owners and the remainder hired cattle herders. The majority of respondents (79%, 82/104) reported a high level of satisfaction with the current animal health programmes in general. The educational level of the respondents varied by satisfaction level: the median (interquartile range; IQR) education level was standard 9 (2-12) for non-satisfied respondents, standard 3 (0-6) for little satisfied and standard 7 (2-11) for very satisfied respondents (P=0.036). Animals are not always treated at FMD inspections points, but satisfied respondents were more likely to seek veterinary assistance (P=0.001). The majority of respondents (92%, 96/104) identified the African buffalo (Syncerus caffer) as a risk factor for FMD outbreaks. Liquid-phase blocking ELISA antibody titres ≥1.6log10 were used to indicate positive serology secondary to FMD vaccination. At the time of sampling and relative to this threshold, 23% (95% confidence interval (CI): 12%-34%) of the sampled cattle had positive serology to SAT-1, 41% (95%CI: 33%-48%) to SAT-2 and 29% (95%CI: 19%-39%) to SAT-3. The median (IQR) time between the previous vaccination and sampling was 189 (168-241) days. The sampled cattle had a longer inter-vaccination interval as scheduled by state veterinary services and antibody levels were low at the time of the study. The majority of respondents expressed high satisfaction with the currently applied FMD vaccination programme, which provides an opportunity for progressive adaption of animal health programmes within the study area.

Clinical and serological response of wild dogs (Lycaon pictus) to vaccination against canine distemper, canine parvovirus infection and rabies.

Wild dogs Lycaon pictuis (n = 8) were vaccinated 4 times against canine distemper (n = 8) (initially with inactivated and subsequently with live attenuated strains of canine distemper) and canine parvovirus infection (n = 8) over a period of 360 days. Four of the wild dogs were also vaccinated 3 times against rabies using a live oral vaccine and 4 with an inactivated parenteral vaccine. Commercially-available canine distemper, canine parvovirus and parenteral rabies vaccines, intended for use in domestic dogs, were used. None of the vaccinated dogs showed any untoward clinical signs. The inactivated canine distemper vaccine did not result in seroconversion whereas the attenuated live vaccine resulted in seroconversion in all wild dogs. Presumably protective concentrations of antibodies to canine distemper virus were present in all wild dogs for at least 451 days. Canine parvovirus haemagglutination inhibition titres were present in all wild dogs prior to the administration of vaccine and protective concentrations persisted for at least 451 days. Vaccination against parvovirus infection resulted in a temporary increase in canine parvovirus haemagglutination inhibition titres in most dogs. Administration of both inactivated parenteral and live oral rabies vaccine initially resulted in seroconversion in 7 of 8 dogs. These titres, however, dropped to very low concentrations within 100 days. Booster administrations resulted in increased antibody concentrations in all dogs. It was concluded that the vaccines were safe to use in healthy subadult wild dogs and that a vaccination protocol in free-ranging wild dogs should at least incorporate booster vaccinations against rabies 3-6 months after the first inoculation.

Cryptococcosis in captive cheetah (Acinonyx jubatus): two cases.

Cryptococcus neoformans is a yeast-like organism associated with pulmonary, meningoencephalitic, or systemic disease. This case report documents 2 cases of cryptococcosis with central nervous system involvement in captive cheetah (Acinonyx jubatus). In both cases the predominant post mortal lesions were pulmonary cryptococcomas and extensive meningoencephalomyelitis. Both cheetahs tested negative for feline immunodeficiency virus and feline leukaemia virus. The organism isolated in Case 2 was classified as Cryptococcus neoformans var. gattii, which is mainly associated with disease in immunocompetent hosts.

Possible vaccine-induced canine distemper in a South American bush dog (Speothos venaticus).

Suspected vaccine-induced canine distemper was diagnosed in a captive female bush dog (Speothos venaticus). Macroscopic lesions included mild congestion of the gastric mucosa and focal consolidation of the lung. Histopathological lesions included status spongiosis, gliosis, widespread eosinophilic, intranuclear and intracytoplasmic inclusion bodies in neurons, astrocytes and gitter cells of the cerebral, cerebellar and spinal white matter.

Immobilization of wild dogs (Lycaon pictus) with a tiletamine hydrochloride/zolazepam hydrochloride combination and subsequent evaluation of selected blood chemistry parameters.

A tiletamine hydrochloride/zolazepam hydrochloride combination was used successfully to immobilize captive untamed wild dogs (Lycaon pictus) (n = 16) at dosage rates ranging from 2.3 to 32.3 mg/kg. Animals remained immobilized for periods ranging from 35 min to 24 hr 14 min. There was a significant positive correlation (r = 0.85, P less than 0.01) between dosage rate and the time immobilized. Profuse salivation and intermittent mild myoclonal contractions were observed in some wild dogs. Mildly reduced partial oxygen and carbon dioxide pressures as well as reduced concentrations of bicarbonate were observed in arterial blood at 10 and 20 min after administration of the drug. Serum concentrations of sodium, potassium, chloride, phosphorus, calcium, magnesium, urea, creatinine, glucose, proteins, albumin, gammaglutamyltransferase, creatinine kinase, aspartate transaminase, alkaline phosphatase, lactate dehydrogenase, insulin, cortisol and thyroxine are presented. These concentrations were found to be in agreement with values previously reported for wild dogs.

The use of long-acting neuroleptics in impala (Aepyceros melampus).

The long-acting neuroleptics perphenazine enanthate and pipothiazine palmitate were found to be effective for the long-term tranquilization of newly-captured and captive impala (Aepyceros melampus). Perphenazine enanthate (1.5 to 5.7 mg kg-1) produced a favourable state of tranquilization with a maximum effect lasting up to 7 d. Pipothiazine palmitate (4.5 mg kg-1) produced tranquilization lasting 16 d. The animals accepted humans inside their pens, at a distance of 0.5 to 4 m, without showing any excitement. No untoward side-effects were observed.

Distemper-like disease and encephalitozoonosis in wild dogs (Lycaon pictus).

Clinical signs of a fatal disease resembling those of canine distemper were observed in two groups of captive wild dog (Lycaon pictus) pups 13 days after vaccination with a commercially available combination vaccine for dogs which contained a live attenuated strain of canine distemper virus. Histopathological examination of tissues revealed the presence of intranuclear inclusion bodies in neurons and lesions resembling canine distemper as well as colonies of an Encephalitozoon sp. in the central nervous system and kidneys. Lesions were observed in both organs which resembled those described in other species infected with Encephalitozoon cuniculi.

Inco-ordination and paresis in a captive lion (Panthera leo).

An adult female lion (Panthera leo) with hind- and forequarter paresis and inco-ordination was examined. An initial diagnosis of a vitamin A deficiency was made, but treatment proved ineffective. A radiological examination showed mild pressure on the spinal cord. A tentative diagnosis of trauma to the cervical vertebrae was made. Response to conservative therapy suggested an aetiology of traumatic origin.

Preliminary investigation into the nutrition of ostrich chicks (Struthio camelus) under intensive conditions.

Twenty ostrich chicks (Struthio camelus) up to 8 weeks of age were fed isocaloric diets containing protein levels of 14%, 16%, 18% and 20%. The highest mean body weight gain was obtained from feeding the 20% protein diet; however, this result was not significantly different at the 0.05 level of probability. Feed conversion favoured the 18% protein group. During the seventh and eighth week of the experimental period some chicks developed leg deformities. Clinical signs, radiological findings and response to calcium supplementation suggested an insufficient amount of calcium in the experimental diets.