Poultry, pig and the risk of BSE following the feed ban in France--a spatial analysis

A spatial analysis was carried out in order to analyse the reason why the risk of Bovine Spongiform Encephalopathy (BSE) was spatially heterogeneous in France, during the period following the feed ban of Meat and Bone Meal to cattle. The hypothesis of cross-contamination between cattle feedstuff and monogastric feedstuff, which was strongly suggested from previous investigations, was assessed, with the assumption that the higher the pig or poultry density is in a given area, the higher the risk of cross-contamination and cattle infection might be. The data concerned the 467 BSE cases born in France after the ban of meat and bone meal (July 1990) and detected between July 1st, 2001 and December 31, 2003, when the surveillance system was optimal and not spatially biased. The disease mapping models were elaborated with the Bayesian graphical modelling methods and based on a Poisson distribution with spatial smoothing (hierarchical approach) and covariates. The parameters were estimated by a Markov Chain Monte Carlo simulation method. The main result was that the poultry density did not significantly influence the risk of BSE whereas the pig density was significantly associated with an increase in the risk of 2.4% per 10 000 pigs. The areas with a significant pig effect were located in regions with a high pig density as well as a high ratio of pigs to cattle. Despite the absence of a global effect of poultry density on the BSE risk, some areas had a significant poultry effect and the risk was better explained in some others when considering both pig and poultry densities. These findings were in agreement with the hypothesis of cross-contamination, which could take place at the feedstuff factory, during the shipment of food or on the farm. Further studies are needed to more precisely explore how the cross-contamination happened.     

Epidemiology of microsporidiosis: sources and modes of transmission

Microsporidia are single-celled, obligate intracellular parasites that were recently reclassified from protozoa to fungi. Microsporidia are considered a cause of emerging and opportunistic infections in humans, and species infecting humans also infect a wide range of animals, raising the concern for zoonotic transmission. Persistent or self-limiting diarrhea are the most common symptoms associated with microsporidiosis in immune-deficient or immune-competent individuals, respectively. Microsporidian spores appear to be relatively resistant under environmental conditions, and species of microsporidia infecting humans and animals have been identified in water sources, raising concern about water-borne transmission. Sensitive and specific immunomagnetic bead separation and PCR-based methods are being developed and applied for detecting microsporidia in infected hosts and water sources for generating more reliable prevalence data. The most effective drugs for treating microsporidiosis in humans currently include albendazole, which is effective against the Encephalitozoon species but not against Enterocytozoon bieneusi, and fumagillin, which has broader anti-microsporidia activity but is toxic in mammals, suggesting a need to identify better drugs. Strategies to capture and disinfect microsporidia in water are being developed and include filtration, coagulation, chlorination, gamma-irradiation, and ozonation.     

Therapy, control and prevention of flea allergy dermatitis in dogs and cats

This article reviews contemporary concepts underlying the design of control strategies for the management of flea allergy dermatitis in dogs and cats. The limitations of palliative symptomatic approaches are noted, as is the fundamental requirement to differentiate simple pulicosis from true hypersensitivity. In the latter case, eradication of fleas from the affected animal and its surroundings has to be an essential aim. The different biological properties offered by modern chemotherapy are defined and the range of techniques for applying active compounds to the animal and its environment described. Factors for consideration when formulating control strategies and selecting chemotherapeutic agents are discussed in the context of the complexities of the flea life-cycle, the host-parasite relationship and client concerns.     

Neutrophil myeloperoxidase measurements in plasma, laminar tissue, and skin of horses given black walnut extract

OBJECTIVE: To compare measurements of myeloperoxidase (MPO) in plasma, laminar tissues, and skin obtained from control horses and horses given black walnut heartwood extract (BWHE). ANIMALS: 22 healthy 5- to 15-year-old horses. PROCEDURES: Horses were randomly assigned to 4 groups as follows: a control group given water (n = 5) and 3 experimental groups given BWHE (17) via nasogastric intubation. Experimental groups consisted of 5, 6, and 6 horses that received BWHE and were euthanatized at 1.5, 3, and 12 hours after intubation, respectively. Control horses were euthanatized at 12 hours after intubation. Plasma samples were obtained hourly for all horses. Laminar tissue and skin from the middle region of the neck were harvested at the time of euthanasia. Plasma and tissue MPO concentrations were determined via an ELISA; tissue MPO activity was measured by use of specific immunologic extraction followed by enzymatic detection. RESULTS: Tissues and plasma of horses receiving BWHE contained significantly higher concentrations of MPO beginning at hour 3. Laminar tissue and skin from horses in experimental groups contained significantly higher MPO activity than tissues from control horses. Concentrations and activities of MPO in skin and laminar tissues were similar over time. CONCLUSIONS AND CLINICAL RELEVANCE: In horses, BWHE administration causes increases in MPO concentration and activity in laminar tissue and skin and the time of increased MPO concentration correlates with emigration of WBCs from the vasculature. These findings support the hypothesis that activation of peripheral WBCs is an early step in the pathogenesis of acute laminitis.     

Genetic parameters estimates for ewes’ behavioural reactivity towards their litter after lambing

In livestock, improving maternal reactivity towards the litter is an important issue in breeding strategies to promote production and animal welfare. As of yet, no studies have investigated the within-breed genetic variation of maternal reactivity in sheep. The objective of this study was to estimate the genetic parameters of maternal reactivity traits. A total of 1,095 primiparous and 1,441 multiparous Romane ewes were phenotyped 24 hr postlambing using a behavioural test (arena test, AT) over a 10-year experimental period. The test consisted of three successive phases evaluating the ewe's attraction to her litter, reactivity to separation from her litter, and reactivity to a conflict between attraction to her litter and avoidance of a motionless human. The ewes were reared exclusively on rangelands (South of France) and lambed outdoors in the spring. High-pitched bleating and low-pitched bleating in the AT were mostly highly heritable (0.39‒0.46). Heritabilities were moderate for proximity to the litter in the presence of a human (0.27) and low for locomotion and vigilance in the AT (0.09‒0.15). The measurements of a given behaviour in the three phases of the AT were highly genetically correlated. Few genetic correlations were found between the different behavioural traits in the AT, the highest correlations being between high-pitched bleating and low-pitched bleating (−0.43 to −0.77). In conclusion, our findings demonstrate moderate-to-high heritability for maternal reactivity traits. These traits could be included in genetic selection schemes to enhance maternal attachment provided there is no unfavourable link with other production traits.     

Histology of two rice bodies isolated from the stifle of an adult draught horse stallion

In the human and equine species, different kinds of free floating intra-articular particles are related to certain disorders. Osteochondral fragments formed during osteochondrosis dissecans are the most common finding in the equine species, whereas in humans rice bodies due to rheumatoid arthritis are more frequent. Herein we report a third type of floating body inside the stifle of an adult draught horse stallion, in macroscopic appearance similar to articular rice bodies known in humans. As revealed by histologic examination, the two particles consist of polypoid degenerated structures derived from synovial villi. Their formation was probably induced by ischemia.     

Myeloperoxidase assay in plasma and peritoneal fluid of horses with gastrointestinal disease

Gastrointestinal disorders, especially strangulating intestinal obstructions, are still a major cause of illness and death in the horse. Circulating lipopolysaccharides may activate both neutrophils and monocytes. The activated neutrophils release myeloperoxidase (MPO), a specific enzyme with strong oxidative activity. The aim of this study was to evaluate MPO concentrations in the plasma and peritoneal fluid (PF) of horses with colic and to check the hypothesis that these concentrations would be higher in a case of strangulating obstruction than in cases of nonstrangulating disease. By using a specific enzyme-linked immunosorbent assay for equine MPO, we determined the MPO concentrations in horses admitted to a clinic for colic. Horses with nonstrangulating or strangulating obstruction of the large intestine (NSLI or SLI), strangulating obstruction of the small intestine (SSI), or inflammatory bowel disease (IBD) were compared with healthy horses. The horses with SLI, SSI, or IBD had significantly higher MPO levels in plasma and PF than did those in the other 2 groups. The mean plasma level was significantly higher in the horses with NSLI than in the healthy horses. High MPO values in PF indicated necrotic bowel. These results show that neutrophil activation occurs during nonstrangulating and strangulating intestinal obstruction in horses and that the plasma and PF MPO concentrations may be a marker of the severity of the disease.     

Transiliac approach for exposure of lumbosacral intervertebral disk and foramen: technique description

Objective— To describe and evaluate a transiliac approach to the L7–S1 disk and intervertebral foramen in dogs.
Study Design— Cadaver study.
Animals— Fresh canine cadavers (n=10).
Methods— A craniolateral approach was made to each iliac wing of 10 fresh canine mixed breed cadavers. An 18 mm hole was drilled in a standardized position through the iliac wing. The musculature connected to the cranial aspects of the sacral wing was dissected and retracted cranially through this iliac window. Endoscopic exploration of the area was performed.
Results— The foramen and intervertebral disk were clearly observed in all specimens without iatrogenic injury of the L7 nerve branch. Access to the foramen was possible in 16 of 20 specimens without excision of the sacral wing; however, it was always partially excised to observe the intervertebral disk which lies more caudally and ventrally.
Conclusion— Transiliac approach to the lumbosacral joint allows direct exposure of the intervertebral disk and foramen through an iliac window. Endoscopic exploration provided good observation of the intervertebral disk and/or foramen.
Clinical Relevance— Transiliac approach could be used for lateral corpectomy and foraminotomy in dogs with degenerative lumbosacral stenosis caused by ventral or ventrolateral disk protrusion, foramen stenosis, or OCD of the L7–S1 joint. Clinical study will be necessary to evaluate the efficacy of this approach.