Current prevalence of adult Uncinaria spp. in northern fur seal (Callorhinus ursinus) and California sea lion (Zalophus californianus) pups on San Miguel Island, California, with notes on the biology of these hookworms

A prevalence survey for hookworms (Uncinaria spp.) was done in northern fur seal (Callorhinus ursinus) and California sea lion (Zalophus californianus) pups on San Miguel Island, CA, in 2000. Intestines of dead pups were examined for adult hookworms in July. These parasites were found in 95% of 20 fur seal pups and 100% of 31 sea lion pups. The number of hookworms varied from 4 to 2142 (mean = 760) in fur seal pups and from 20 to 2634 (mean = 612) in sea lion pups. A direct relationship was evident between body condition and number of hookworms in the pups; that is, pups in poor condition had fewer hookworms than those in good condition. There was a decline in the number of hookworms in sea lion pups in 2000 compared to collections in 1996. Eggs of Uncinaria spp. were found in rectal feces (collected in late September and early October) of none of 35 (0%) live fur seal pups and 41 of 48 (85%) live sea lion pups. Packed cell volume values, determined for most of the same live pups, were essentially normal for C. ursinus but were much lower than normal for most Z. californianus. Hookworm larvae were not found in blubber of fur seal and sea lion pups or in rookery sand in July. Rookery sand, positive for live hookworm larvae when put in a refrigerator, was negative at removal 2.5 years later. The average number of eggs in utero of female hookworms was 285 for three specimens from a fur seal pup and 281 from three specimens from a sea lion pup. One hookworm larva was recovered from milk stripped from the teats of a stranded Z. californianus female at The Marine Mammal Center, Sausalito, CA.     

Optimising spring oral vaccination campaigns of foxes against rabies

To optimise spring vaccination campaigns the following set of data has been analysed; (i) population dynamics of the red fox, (ii) onset and progress of the reproductive season, and (iii) maternal immunity and the immune response of fox cubs to oral vaccination. The field data originated from foxes caught in Bavaria, Germany. The results of our analysis clearly demonstrate that certain periods during spring are less suitable for bait distribution. If the objective of a vaccination campaign is to reach only the adult foxes, it is suggested to conduct the campaign during the first half of March. If also young foxes are to be vaccinated, baits should not be distributed before the end of May in previously baited areas, because a large segment of the young fox population can not be vaccinated effectively before this date as a result of maternally transferred immunity. In areas vaccinated for the first time, baits can be distributed earlier, since 5 weeks old cubs are already immunocompetent.     

Two new variants of the Rhodococcus equi virulence plasmid, 90 kb type III and type IV, recovered from a foal in Japan

Calves were vaccinated orally, subcutaneously or intraperitoneally with a smooth, plasmid-cured strain of Salmonella enterica serovar typhimurium, strain 81. Oral vaccination was not effective, as only 1/5 calves survived challenge with virulent S. typhimurium. Strain 81 was attenuated for calves, as only a slight rise in rectal temperatures was detected after vaccination. The organism was excreted by some calves in the faeces, but no signs of diarrhoea were observed after vaccination. After parenteral vaccination, strain 81 was able to reach the intestines, gastric associated lymphoid tissues and other internal lymphoid tissues and remained viable for up to 14 days in the bovine host. After oral challenge with a virulent strain, 9/10 vaccinated calves survived challenge as opposed to 4/10 control calves (p<0.5). Diarrhoea was present in all calves of the control groups, but in only 4/10 of the vaccinated calves. The clinical reactions of the vaccinated calves were milder than in the control calves, as the rises in rectal temperatures were lower, diarrhoea was less severe, and the challenge strain was present in fewer organs from vaccinated calves than control calves. This study showed that parenterally administered Salmonella vaccines can induce both mucosal and systemic immunity, and it is postulated that this capability of strain 81 is related to its colonisation of lymphoid tissues and other systemic and intestinal tissues. This study confirmed that plasmid-cured strains were attenuated in the bovine host and conferred significant protection after parenteral vaccination, but not oral vaccination.     

MMP-9 as a marker of inflammation in tracheal epithelial lining fluid (TELF) and in bronchoalveolar fluid (BALF) of COPD horses

Gelatinolytic activity was analysed to study whether elevated activity previously found at the tracheal level of the respiratory tract of horses with chronic obstructive pulmonary disease (COPD) could also be found at the lower part of the respiratory tract. Furthermore, presence and significance of the gelatinolytic matrix metalloproteinases (MMPs) MMP-2 and MMP-9 in respiratory secretions of healthy and COPD horses were determined. Elevated gelatinolytic matrix metalloproteinases were detected in bronchoalveolar and tracheobronchial secretions from COPD horses. The main pathologically elevated MMP was characterised to be MMP-9. Significantly increased MMP-9 activities as measured by gelatin zymography and Western blotting were found in all the respiratory samples from COPD horses compared to healthy horses. Elevation of active MMP-9 paralleled with increased gelatinase-associated lipocalin levels. Bronchoalveolar lavage fluid (BALF) epithelial cells, macrophages, neutrophils and lymphocytes expressed MMP-9 immunoreactivity demonstrated by immunocytochemistry and MMP-9 mRNA was expressed by bronchial epithelial cells of lung tissue section shown by in situ hybridisation. MMP-2 seems not to play a major role in chronic lung inflammation. No clear differences in MMP-2 or MMP-14 (a potent MMP-2 activator) levels were found when comparing the samples from COPD or healthy horses. These results suggests that MMP-9 could serve as a potential diagnostic marker for the active ongoing tissue remodelling in the acute phase of equine COPD. Increased gelatinolytic activity could be found at both tested respiratory tract levels. Therefore, tracheal epithelial lining fluid (TELF) samples can usefully serve as diagnostic material for detection of increased levels of the main gelatinolytic MMP, MMP-9, representing the entire diseased lung.     

Client donation program for acquiring dogs and cats to teach veterinary gross anatomy

A donor program for procuring dogs and cats to meet the needs of anatomical instruction was initiated six years ago at Tufts University School of Veterinary Medicine. The program was initiated in order to comply with state regulations that preclude the use of shelter animals and to satisfy ethical objections of students and faculty. The donor program has successfully met the animal needs for teaching gross anatomy and, in addition, provides opportunities to integrate clinical perspectives and ethics beginning from the first year of veterinary education.     

Chylothorax in a dog with pulmonary lymphangiosarcoma

Lymphangiosarcoma of the pulmonary pleura was found to be the cause of persistent chylothorax in an eight-year-old, intact male golden retriever. After a two-month course of medical management, a lymphangiogram and thoracic duct ligation were performed with the objective of decreasing further effusion. At surgery, gross lung pathology was biopsied and yielded a histopathological diagnosis of pulmonary pleural lymphangiosarcoma. A relatively rare tumor, lymphangiosarcoma of the pulmonary pleura has not previously been documented as a source of chylothorax in the dog.     

Organogenesis of lung and kidney in Thoroughbreds and ponies

Equine lung and kidney organogenesis has not previously been examined with the use of unbiased stereological techniques. The present study examined healthy (control) pony and Thoroughbred lungs and kidneys to establish baseline data of organ development from before birth until maturity at age 3-18 years. Whole left lungs and kidneys were collected from 45 equine postmortem examinations (34 Thoroughbred, 11 pony). Stereological techniques were used to estimate whole kidney, cortex and medulla volume, total glomerular number and volume-weighted mean glomerular volume, lung volume, total terminal bronchiolar duct ending number and total gas exchange surface area. Lungs were demonstrated to be more developed at birth in ponies compared with Thoroughbreds. Thoroughbreds showed continued lung development after birth, a unique micromorphogenic postnatal development. Kidneys were developed equally in ponies and Thoroughbreds. This study has provided data on the baseline development of the equiune lung and kidney which can be used in further studies to examine whether the development of these organs is affected by specific illnesses.