Natural infection of broiler breeder chickens with endemic apathogenic Newcastle disease virus and their subsequent response to vaccination with a live V4 Newcastle disease virus vaccine

Flocks of broiler breeder chickens housed on a commercial farm were monitored from 13 w of age for natural infection with endemic lentogenic Newcastle disease virus (NDV). Seroconversion was first detected at 17 w. By 24 w, all 8 flocks had achieved peak log2 mean haemagglutination inhibiting antibody titres of up to 4.8. Antibody titres then declined and rose again over several months, suggesting cyclic reinfection with NDV. A lentogenic NDV indistinguishable from V4 was isolated from the cloaca of one bird at 18 weeks of age. At 54 weeks of age, 6 of 8 flocks were vaccinated en masse with live V4 NDV vaccine, 3 flocks by drinking water and 3 flocks by aerosol. All flocks were serologically monitored for a further 8 w. Drinking water vaccination induced an anamnestic response in 3 flocks, showing that flocks with pre-existing active immunity to NDV may be successfully vaccinated with V4. However, in all aerosol vaccinated flocks, the procedures failed to induce a response different to that observed in unvaccinated flocks. The serological response to vaccination was greater in sires than in dams.     

Detection of reserpine in horses by high-performance liquid chromatography

SUMMARY A high-performance liquid chromatography (HPLC) assay was developed for the detection of reserpine. The assay was used to monitor the plasma concentrations of the drug given intramuscularly on one or two occasions to five horses. The blood concentrations of reserpine varied quite considerably between horses given the same dose of the drug. However, on average, reserpine could be detected consistently, and quantified, for 48 h after a single dose of 2.5 mg, and for a similar period after the second of two 2.5 mg doses given 13 d apart. Because of the apparently large variability in the pharmacokinetics of reserpine in horses, exact times cannot be given beyond which the drug will no longer be detectable in the plasma. However, following two doses of 2.5 mg reserpine given 13 d apart, at least 7 d must elapse after the second dose before there is no drug detectable in the plasma of most horses.     

Comparison of normograde and retrograde intramedullary pinning of feline tibias

This study evaluated the effects of normograde and retrograde intramedullary pinning of mid-diaphyseal fractures of the feline tibia on the anatomical structures of the stifle joint. Using the paired pelvic limbs from five mature feline cadavers, a transverse, mid-diaphyseal osteotomy was performed, and each tibia was pinned in a normograde or retrograde fashion. The stifle joints were examined to determine the pin exit site and measure the distance from the exit site to pertinent anatomical structures of the stifle joint. Neither normograde nor retrograde intramedullary pinning resulted in damage to the cruciate ligaments, menisci, intermeniscal ligament, femoral condyles, or joint capsule. The patellar tendon was penetrated in all five tibias during retrograde pin insertion.     

Serum and mucosal antibody responses and protection in pigs vaccinated against Mycoplasma hyopneumoniae with vaccines containing a denatured membrane antigen pool and adjuvant

Objective To investigate the protective efficacy of a pool of denatured membrane protein antigens of Mycoplasma hyopneumoniae (J strain) in the molecular size range 70 to 85 kDa (F3 antigen) in combination with adjuvants for pigs challenged with M hyopneumoniae .
Design A vaccine efficacy experiment with assessment of serum and respiratory tract antibody responses.
Procedure F3 antigens were emulsified with five different adjuvants. To groups of three pigs per vaccine, four vaccines were given by intramuscular injection, and two vaccines, including one of those given intramuscularly, were given by intraperitoneal injection.
Results Compared to six unvaccinated pigs, animals vaccinated with F3 antigen displayed significantly reduced pneumonia (54% reduction in mean lung score) following experimental challenge. Analysis of post-vaccination, pre-challenge IgG and IgA ELISA antibody absorbances in serum and respiratory tract washings revealed no correlation with lung score. Six weeks after challenge, pigs previously vaccinated intramuscularly mostly demonstrated greater IgG and IgA responses in respiratory tract washings, and greater IgG serum antibody responses, than those vaccinated by intraperitoneal injection.
Conclusion Pigs vaccinated with M hyopneumoniae antigens in the molecular size range of 70 to 85 kDa showed a significant reduction in lung lesions compared with unvaccinated control animals after experimental challenge. IgG and IgA antibody concentrations in serum and respiratory tract washings after vaccination do not provide a useful prognostic indicator of protection from enzootic pneumonia.     

Occurrence of cutaneous infections of Myxobolus episquamalis (Myxozoa: Myxobolidae) in sea mullet, Mugil cephalus L, in Australia

Objective To report the occurrence of Myxobolus episquamalis in sea mullet, Mugil cephalus L , caught in estuaries in eastern and western Australia.
Design A prospective study of commercial catches of mullet in the Clarence River of NSW and individual cases from other areas.
Results The organism caused pale, white to pink, raised lesions on the scales and fins of sea mullet. Occurrence of infection was highest in spring and in a marine (down-river) environment compared to a brackish environment. Up to 6% of fish were affected in commercial catches.
Conclusion The infection is widespread in Australian mullet, but rarely causes significant economic loss.