Feed Containing Novacq Improves Resilience of Black Tiger Shrimp,Penaeus Monodon,to Gill‐associated Virus‐induced Mortality

The ability of Novacq to improve resilience of black tiger shrimp, Penaeus monodon, to infection and mortality induced by gill‐associated virus (GAV) was investigated. Over a 26‐d period, shrimp were fed pellets with or without 10% Novacq. Following this, four replicate tanks, each containing 10 shrimp that had been fed either diet, were maintained as‐is, injected with saline or injected with GAV inoculum (i.e., 40 shrimp for each of the six groups). For shrimp (n = 20) in two of each group of four tanks, survival was monitored daily over 14 d and a pleopod was sampled from each shrimp on Days 0 and 14. For the other two tanks, a pleopod was sampled from each shrimp on Days 0, 3, 7, 10, and 14 to track changes in GAV loads over time. Survival was significantly higher (P < 0.05) from Day 7 onward among the group fed Novacq. GAV infection loads appeared to vary more between individuals in the Novacq diet cohort, but overall were not reduced significantly at any time points post‐challenge compared to shrimp tested from the Control diet cohort.     

Effect of bandaging on second intention healing of wounds of the distal limb in horses

Objective   To evaluate the effect of a non-occlusive dressing incorporated in a 3-layer bandage on second intention healing of wounds of the distal portion of the limb.
Study Design   Untreated wounds in 33 adult horses used in four studies using the same wound-healing model conducted over 5 years.
Methods   Standardised, full-thickness wounds were made in the skin overlying the dorsomedial aspect of the mid-metacarpus; 17 horses were bandaged with a non-occlusive dressing covered by gauze-coated cotton wool that was compressed with adhesive tape; 16 horses were left unbandaged. Wounds were photographed weekly for 9 weeks and the images were analysed electronically.
Results   There were significant effects associated with bandage (P < 0.0001), week (P < 0.001), and bandage by week interaction (P < 0.0001). There was no difference in wound area at the first time-point after wound creation (P = 0.38). After week 1, there was a difference between bandaged and unbandaged wounds in wound area at each measurement until the end of the study. Bandaged wounds showed greater and more prolonged retraction. Unbandaged wounds retracted for 2 weeks before beginning to contract, whereas bandaged wounds continued to retract for 3 weeks. In bandaged wounds excess granulation tissue required regular trimming, but not in unbandaged wounds. There was no difference between groups in the total days to healing or the overall rate of healing.
Conclusions   These results should be treated with caution until validated with contemporaneous, controlled studies. Covering a wound with a non-occlusive dressing in a 3-layer bandage led to greater wound retraction, modulated the rate of wound contraction and promoted excessive granulation tissue. If excessive granulation tissue is excised regularly, bandaging has no effect on total time to healing.     

Introduction and multiplication of bovine Babesia in human cells.

Bovine erythrocytes parasitised with Babesia major were fused with human HeLa cells by means of Sendai virus. B major parasites entered the HeLa cell cytoplasm and in some cases underwent multiplication over a period of three days.     

Effect of chronic trypanosomiasis on immunization against East Coast fever

Two experiments were carried out in which uninfected cattle, or cattle chronically infected with Trypanosoma congolense, were immunized by the infection and treatment method against East Coast fever (ECF; Theileria parva infection). Chronic trypanosomiasis did not prevent cattle mounting an effective immunological response to ECF immunization and resisting subsequent lethal challenge. There appeared to be no difference in the level or quality of immunity between uninfected cattle and trypanosome-infected cattle. Thus, T. congolense infection on its own does not appear to provide a constraint to ECF immunization in the field.     

Age resistance to Theileria parva bovis infection in calves

Data collected in the Zimbabwean province of Mashonaland-West, in the period 1980-1988, showed that mortality in calves owing to Theileria parva bovis infection (January disease) was significantly lower in animals younger than 7 months than in older cattle. Groups of seven Holstein-Friesian calves from non-immune dams aged approximately 1, 4, 7, 10 and 13 months were infected with a Theileria parva bovis tick-derived stabilate. The dose chosen was lethal for 40% of the calves in the trial. Mortality was highest in the 4-month age group. The reactions in the 7-, 10- and 13-month age groups became progressively milder. The reactions in the 1-month old calves were the least marked, being very mild. The age-related resistance in the youngest calves, as can be concluded from our results, is only of short duration and cannot explain the lower incidence of January disease observed in calves in the field.     

In vitro Effect of Zearalenone and α-Zearalenol on Boar Sperm Characteristics and Acrosome Reaction

This study was conducted to determine the in vitro effects of three different concentrations (125, 187.5 and 250 microM in diluted semen) of zearalenone (zen) and alpha-zearalenol (alpha-zen) on boar sperm. Semen parameters such as motility, viability and spontaneous acrosome reaction were evaluated. From the results it was shown that both zen and alpha-zen affected the sperm characteristics significantly (p < 0.05), except for alpha-zen at the low concentration which did not decrease the percentage of live reacted spermatozoa significantly. In conclusion, zen and alpha-zen are directly toxic when they affect boar semen in vitro and consequently decrease the fertilization ability of the sperm. The higher the concentration of mycotoxin tested, the greater the decline of sperm parameters noticed. The influence of mycotoxins was found to be time- and dose-dependent.     

Indirect fluorescent antibody test for experimental and epizootiological studies on East coast fever (Theileria parva infection in cattle). Evaluation of a cell culture schizont antigen fixed and stored in suspension

A schizont antigen for the indirect fluorescent antibody test against Theileria parva was prepared from a T parva-infected bovine lymphoblastoid cell line by fixing the cells in suspension with a mixture of acetone and formaldehyde. The antigen was stored in suspension in phosphate buffered saline for one and a half years at -60 degrees C without loss of activity; the antigen could also be lyophilised. The fluorescence of the intracellular schizonts was bright and specific with T parva positive bovine control serum and absent with negative bovine control serum and Theileria mutans positive bovine control serum. Fluorescence of the lymphoblastoid cell itself was observed with Trypanosoma brucei positive control serum and some bovine test sera: this fluorescence, which masked the intracellular schizonts, was eliminated by absorbing the sera in the supernatant of sonicated lymphocytes obtained from bovine lymph nodes. The antigen was evaluated with sera from cattle experimentally infected with T parva. In an epizootiological study on East Coast fever in the Coast Province of Kenya, there was good correlation between the serological responses of cattle to T parva schizont antigen and the distribution of Rhipicephalus appendiculatus ticks.