[Adenocarcinoma of the paranasal sinuses in sheep: First case description in Morocco]. / Adenokarzinom der Sinus paranasales bei Schafen: Erstbeschreibung in Marokko.

INTRODUCTION: Small ruminant sinus adenocarcinoma (ENA) is a contagious disease caused by a beta retrovirus called Enzootic Nasal Tumor Virus or ENTV. The first cases were sporadically diagnosed in Morocco in 2018. However, in the last two years, ENTV has appeared enzootic in three herds of the Sardi breed. The annual incidence varied between 5 and 20 %. Most cases involved female animals aged 15 to 42 months. The disease developed within 2 to a maximum of 6 months. Diseased animals presented with progressive weight loss and increased mortality or needed to be slaughtered. The condition associated mainly with unilateral skull deformation, serous or seromucous nasal discharge with dyspnea, and in some individuals an exophthalmos. During pathology tumor-like masses were found in the paranasal sinuses, which showed the growth of an expansive and organized epithelial neoplasm on histopathology. After an overview of the differential diagnoses that can lead to confusion with ANE, the authors investigate why the disease occurs more frequently in Morocco and particularly in the Sardi breed.

INTRODUCTION: L'adénocarcinome des sinus nasaux des petits ruminants (ANE) est une maladie contagieuse, provoquée par un betaretrovirus appelé l'Enzootic Nasal Tumor Virus ou ENTV. Les premiers cas ont sporadiquement été diagnostiqués au Maroc en 2018. Cependant, durant les deux dernières années, l'ANE a sévi de manière enzootique dans trois troupeaux, tous naisseurs, qui exploitent la race Sardi. L'incidence annuelle varie de 5 à 20 %. La majorité des cas étaient des femelles, âgées entre 15 et 42 mois. La maladie évolue en 2 à 6 mois au maximum. Les malades maigrissent progressivement et la quasi-totalité meurt si elle n'est pas abattue avant. L'affection associe principalement des lésions de la face, avec déformation du crâne souvent unilatérale, des écoulements nasaux séreux ou séro-muqueux avec difficulté respiratoire et l'exophtalmie chez certains individus. L'autopsie a permis de mettre en évidence des masses tumorales dans les sinus. A l'examen histopathologique, les masses tumorales correspondent à un néoplasme épithélial expansif et organisé. Les auteurs, après avoir passé en revue les diagnostics différentiels pouvant prêter à confusion avec l'ANE, s'interrogent sur les raisons de sa recrudescence au Maroc, particulièrement chez la race Sardi.

[Natural Cryptosporidium sp. infection in broiler chickens in Morocco]. / Infection naturelle à Cryptosporidium sp. chez le poulet de chair au Maroc.

The prevalence of cryptosporidium infection was assessed in 38 broiler flocks. Two-hundred-and-twenty-five broilers were subjected to clinical and post-mortem examinations. Analyses of impression smears and tissue samples from the intestine, bursa of Fabricius and trachea revealed Cryptosporidium sp. in 37% of broiler flocks investigated. The prevalence of infection within flocks varied from 14 to 100%. High incidence of Cryptosporidium infection occurred in 36 to 45-day-old broilers (52%), but Cryptosporidium was not found in chickens under 25 days of age. Cryptosporidium sp. was detected in 24% of bursa examined, intestine (15%) and trachea (2%). In the bursa of Fabricius, Cryptosporidium-induced epithelial lesions were associated in most cases (94%) with lymphoid atrophy and depletion.

Effects of aflatoxin B1 on chicken chondrocytes in culture.

In vitro effects of aflatoxin B1 on DNA and proteoglycan synthesis were assessed by measuring tritiated thymidine and radiosulfate incorporation by chicken chondrocyte cultures. Chondrocytes were harvested from the growth-plate cartilage of a 35-day-old chicken, cultured in triplicate, and treated with 0, 1, 5, 10, or 25 micrograms aflatoxin B1/ml of culture medium. The cultures were then spiked separately with [3H]thymidine or [35S]sulfate. After the cells, matrix, and medium were harvested, radioactivity was measured by a scintillation counter. Aflatoxin B1 resulted in a dose-dependent inhibition of DNA synthesis, as measured by tritiated thymidine incorporation by chicken chondrocytes: 54.6%, 30.9%, 25.9%, and 5.9% of control in cultures treated with 1, 5, 10, and 25 micrograms aflatoxin B1/ml of culture medium, respectively (P < 0.05). Sulfated proteoglycan synthesis, as measured by radiosulfate incorporation in chondrocyte cultures, was decreased in the media and intercellular matrix by all aflatoxin B1 levels. Compared with controls, 21% less (P < 0.05) radiosulfate was incorporated into non-matrix macromolecules of the medium fraction from chondrocytes exposed to 1 microgram aflatoxin B1/ml. However, 5 micrograms aflatoxin B1/ml was necessary to produce a significant decrease in radiosulfate incorporation in proteoglycans of intercellular matrix (34% less than controls). The ratios of the means of radiosulfate incorporation into intercellular macromolecules to the means of tritiated thymidine incorporation indicated that aflatoxin B1 inhibited DNA synthesis more than proteoglycan synthesis.

The natural occurrence of aflatoxin B1 in Moroccan poultry feeds.

The occurrence of AFB1 in Moroccan poultry feeds and their ingredients was evaluated. Thirty poultry farms and 4 feedmills were surveyed from September 1989 to June 1991, and 300-500 g each of feeds (corn, sorghum, wheat bran, soybean meal, cottonseed meal, sunflower meal, finished feeds) were sampled. Additionally, on farms with suspected mycotoxin problems, necropsies of affected chickens were performed for gross and microscopic examinations. A total of 315 samples were analysed for AFB1 using a semi-quantitative enzyme linked immuno-sorbent assay (ELISA kits) and thin-layer chromatography. In feedmills, 4% of samples contained AFB1; 17% among sunflower meal samples (20-80 ppb) and 4% among corn (110 ppb) and mixed feed samples (20-110 ppb). On poultry farms, 17% of samples were found contaminated with AFB1; 20% were positive among pellets and 16% among crumbles and 15% mash feeds. The level of contamination ranged from 20 ppb to 200 ppb, except for 4 samples that contained high levels of AFB1 (2000-5625 ppb). These highly-contaminated samples were associated with clinical aflatoxicosis in broiler chickens. The most frequent incidence of AFB1 contamination and the highest AFB1 contamination occurred in feeding troughs (23%). Aflatoxins should be considered potential contaminants of poultry feeds under Moroccan conditions.