Sarcocystis infections in gazelles at the King Khalid Wildlife Research Centre, Saudi Arabia

The prevalence of Sarcocystis species in muscle samples from gazelles kept as breeding groups at the King Khalid Wildlife Research Centre, Saudi Arabia, was determined by fibreoptic examination, pepsin digestion and histological techniques. No macroscopic sarcocysts were detected by fibreoptic examination, and the overall prevalence of Sarcocystis was 66 x 7 per cent by pepsin digestion, and 39 x 9 per cent by histological examination. By digestion, the tongue contained the highest density of bradyzoites in Gazella dorcas, and Gazella gazella erlangeri, the oesophagus in Gazella subgutturosa marica and skeletal muscle in Gazella gazella and Gazella thomsoni. Skeletal muscle was least affected in G dorcas, the oesophagus in G gazella, and the diaphragm in G g erlangeri, G s marica and G thomsoni. By histology, the heart contained most microcysts, except in G g erlangeri, in which the tongue was most affected. No single tissue type was therefore suitable for the diagnosis of sarcocystosis in this multispecies collection, although digestion was more sensitive in detecting infection than histology. The level of Sarcocystis infection was significantly higher in free-ranging gazelles kept in a main enclosure than in gazellas kept in breeding pens, and higher in adult gazelles than in juveniles.     

Epidemiologic study of Giardia sp. infection in dairy cattle in southeastern New York State

To identify animal and management factors associated with the risk of Giardia sp. infection in dairy cattle in southeastern New York State, an observational analytical epidemiologic study was conducted. A random sample of 2943 animals in 109 dairy herds located in five counties of southeastern New York was selected from the target population. Fecal samples were collected from animals in the study population and examined for the presence of Giardia sp. using a quantitative centrifugation concentration flotation technique. Data on each animal, and on general management, maternity, preweaning, and postweaning practices were collected by personal interview with the farmer or farm manager. The significance of association of these factors, within each management practice group, with the risk of infection was evaluated using the logistic regression analysis. Weighted indices for each of these four groups were developed, and were evaluated together with the age of the animal and season of sampling for their significance of association with the risk of infection using mixed effect logistic regression analysis. Only the maternity management practices, age of the animal, and the season of sampling were significantly associated with the risk of infection with Giardia sp. Summer housing of bred heifers, on pasture or in tie stalls, was associated with increased risk of infection. Calves that were fed fresh colostrum or separated immediately after birth from the dam were at decreased risk of infection. The risk of infection decreased with the age of the animal and varied by the season of sampling. There was no significant extra binomial variation in the risk of infection in this data. If consideration is to be given to reducing the risk of infection with this parasite, management must be a top priority, especially in younger animals.     

The effect of coccidian infection on the gut microflora of Nubian goat kids

Enteric coccidiosis was experimentally induced in Nubian goat kids by the oral inoculation of 1.5 x 10(6) sporulated oocysts of five mixed Eimeria species. Diarrhoea was the major manifestation of the disease, which terminated fatally within 19 to 25 days postinfection. Faecal excretion of oocysts was first detected on day 8 (mean 58 x 10(2)) with a maximum shedding (mean 16.39 x 10(5)) on day 14 post-infection. In addition, noticeable alterations were further observed on the normal constituents of the gut microflora in coccidia-infected kids. These changes were characterized by progressive reduction of the Gram-positive population from 84% pre-infection to 24.3% after the onset of diarrhoea. On the other hand, the Gramnegative population was conversely increased from 16% pre-infection to 75.7% after diarrhoea. At this stage (diarrhoea) E. coli was the most dominant organism amongst the various constituents of the gut microflora.     

Characteristics of digital flexor tendon sheath fluid from clinically normal horses

Physical, biochemical, and cytologic properties of synovial fluid from digital flexor tendon sheaths of clinically normal horses were investigated. Tendon sheath fluid was pale yellow, clear, and did not clot. Volume of fluid within a tendon sheath varied minimally, with a mean of 2.11 ml. Total erythrocyte counts were higher than values observed in normal equine joint fluid, whereas values for total leukocyte count (770 +/- 73 cells/mm3), viscosity (6.05 +/- 0.58 cs), and protein concentration (7.87 +/- 0.03 mg/ml) were similar to those in joint fluid. Large mononuclear cells were the predominant synovial fluid cell type. Mean hyaluronic acid concentration (0.74 +/- 0.02 mg/ml) and mucinous precipitate quality were lower than values in joint fluid.     

The risk of severity of limb injuries in racing thoroughbred horses.

A retrospective study was carried out to identify factors which predisposed Thoroughbred horses to severe injuries, as compared to less severe injuries, while racing on New York Racing Association (NYRA) tracks during the period of January 1986 to June 1988. A severe injury was defined as an injury which led to humane destruction of the horse. A less severe injury was defined as a horse which didn't race within 6 months following a muscular, ligament, tendon, or skeletal injury on the racetrack. The data were obtained from the Horse Identification Department records kept by the Chief Examining Veterinarian of NYRA and included 55 severely injured horses and 245 less severely injured horses. Multiple logistic regression analysis was used to identify factors associated with the risk of severe injuries compared to less severe injuries in those horses. There was a significant association between track and the risk of severe injury (horses raced on Belmont and Saratoga were more likely to develop a severe injury compared to horses raced on Aqueduct Main). The track surface was also associated with the risk of severe injury (horses raced on a firm turf had a significantly lower risk of severe injury associated with the track was significantly modified by the track condition (horses raced at Belmont when it was muddy had a significantly increased risk compared to Aqueduct dirt). Horses were more likely to experience severe injury in the early part of the race (less than or equal to 6 furlongs) than the latter part of the race (greater than 6 furlongs). The risk of severe injury decreased with the age of the horse.     

Clinic accessions to Maiduguri Veterinary Teaching Hospital: 1986 to 1990

A survey of disease conditions of dogs presented to the small animal unit of the University of Maiduguri Veterinary Teaching Hospital, between January 1986 and December 1990, was undertaken. A total of 559 cases was recorded during this period and these were divided into 13 groups according to the distribution of the following conditions: Ectoparasitism 21.1 per cent, helminthiasis 20.4 per cent, vaccination requests 13.4 per cent, trauma 11.1 per cent, orthopaedic problems 7.9 per cent, protozoan infections 6.3 per cent, castration 3.9 per cent, dermatitis 3.6 per cent, pneumonia 3.6 per cent, obstetrical problems 3.2 per cent, viral infections 2.5 per cent, cosmetic surgery 1.6 per cent and neoplasm (transmissible venereal tumour) 1.4 per cent.     

Serological relationship between strains of Pasteurella multocida

The serological inter-relationships of twenty four strains of Pasteurella multocida represented by 11 reference strains, each representing a different serogroup, and 13 strains from cattle with hemorrhagic septicemia were determined by agglutination and gel diffusion tests. There was agreement between the results of the two procedures indicating that both tests were probably employing the same antigen. Although all strains had strong serogroup-specific agglutinating and precipitating properties, they exhibited varying degrees of cross-reactivity. Strains M4, V A3 and Kobe 6 and strains R473 and 147 showed a close relationship with each other and might be regarded as having the same somatic antigen. Field isolates showed a distribution of reactions about the homologous titers of somatic groups 6, 7 and 8.     

Effects of deltamethrin on ventral nerve cord activity in the cockroach

The effects of varying concentrations of deltamethrin on a number of the parameters of electrophysiological activity in the cockroach ventral nerve cord have been studied. Deltamethrin, at concentrations greater than 100 nM, caused repetitive firing in the central nervous system (CNS), prior to conduction block, the effect getting faster as the concentration was increased. Whilst 10-nM deltamethrin eventually caused conduction block with no apparent increase in the level of CNS activity, it induced a gradual decrease in the amplitudes of all spike activity. Deltamethrin at 10μM induced a significant increase in the latency of electrically evoked responses, and this was attributed to a synaptic mechanism. It was shown for the first time that 10-μM deltamethrin causes a significant elevation of the extra-axonal K⁺ activity; the possible consequences of this are discussed.     

Infection rates of Theileria annulata in the salivary glands of the tick Hyalomma marginatum rufipes

Theileria annulata was experimentally transmitted to cattle on two occasions by the two-host tick Hyalomma marginatum rufipes. Transmission was transstadial; engorged nymphs fed on Theileria annulata-infected calves transmitted the disease as adults. Salivary glands of all partially fed and incubated adult ticks were heavily infected with Theileria parasites. Immatures attached rapidly and fed successfully on cattle. However, since the immature stages of this species normally feed on birds, this tick is unlikely to be an important vector in the field.