Development and characterization of a novel variant of long-acting bovine follicle-stimulating hormone (brscFSH).

Assisted reproduction is a key aspect of modern animal breeding, providing valuable assistance in improving breeding programs. In this field, the administration of exogenous hormones, such as follicle-stimulating hormone (FSH), plays a crucial role in the induction of multiple ovulations. However, commercial FSH used in veterinary practice has been derived primarily from pituitary glands, obtained mostly from pigs for nearly four decades. Although these hormones have contributed significantly to the advancement of assisted reproductive techniques, they have certain limitations that warrant further improvements. These limitations include contamination with luteinizing hormone (LH), the potential risk of pathogen contamination, the potential to trigger an immune response in non-pig species, and the short half-life in circulation, requiring the implementation of complex 8-dose superovulation schedules. Our research team has developed and characterized a new variant of bovine follicle-stimulating hormone (bscrFSH) to address these limitations. The new hormone is produced recombinantly in CHO cell cultures, with a specific productivity of about 30 pg/cell/day. The bscrFSH can be purified to a high purity of 97 % using a single step of immobilized metal affinity chromatography (IMAC). N-glycan analysis of bscrFSH showed that approximately 74 % of the glycans corresponded to charged structures, including mono-, di-, tri-, and tetra-sialylated glycans. Superovulation trials conducted in cattle revealed that bscrFSH, administered at a total dose of about 0.5 µg per kg of body weight, using a decrescent schedule of 4 doses with 24-h intervals, resulted in an average yield of 8-12 transferable embryos per animal. Further research is required; however, the preliminary findings indicate that bscrFSH, currently packaged under the provisional brand name of Cebitropin B, holds potential as a commercial product for assisted reproduction in ruminants.

Update on Cyclospora cayetanensis, a food-borne and waterborne parasite.

The coccidian parasite Cyclospora cayetanensis is recognized as an emerging pathogen that causes protracted diarrhea in humans. The first cases of Cyclospora infection were reported in the late 1970s and were observed among expatriates and travelers in regions where infections are endemic. Since then, Cyclospora has been considered a cause of traveler's diarrhea. Epidemiological investigations were reported and examined in areas of endemicity even before the true identity of Cyclospora was elucidated. Cyclospora was fully characterized in the early 1990s, but it was not until the 1995 Cyclospora outbreak in the United States and Canada that it caught the attention of the public and physicians. The biology, clinical presentation, epidemiology, diagnosis, treatment, and control of cyclosporiasis are reviewed, with a focus on diagnostic assays currently being used for clinical and environmental samples. Challenges and limitations in working with Cyclospora are also discussed.

Inmunodiagnóstico de fasciolosis bovina mediante Elisa y Western Blot / Immunodiagnosis of bovine fasciolosis by Elisa and Western Blot

Se evaluó y caracterizó la respuesta inmune humoral de bovinos naturalmente infectados con fasciola hepatica frente a un extracto total de antígenos de excreción-secreción (E-S) y a una fracción antigénica semipurificada cromatográficamente (<30 kDa), seleccionada previamente por su eficiencia diagnóstica en otras especies. Ambos preparados antigénicos fueron analizados mediante ELISA en microplaca y electroforesis en geles de poliacrilamida en condición de denaturación (SDS-PAGE) y posterior inmunoelectrotransferencia enzimática o Western blot. Para ello se emplearon 52 sueron de bovinos con fasciolosis comprobada mediante examen post mortem, 18 sueros de animales sin la infección y 48 sueros de vacunos infectados con hidatidosis, pero sin fasciolosis. La sensibilidad y especificidad obtenidas en el ELISA con el extracto crudo E-S fueon de 53 por ciento y 100 por ciento, respectivamente, en tanto que con la fraccion semipurificada a igual especificidad (100 por ciento) se presentó una sensibilidad mayor (90 por ciento). A través de Western blot, empleando el extracto antigénico total E-S hubo un reconocimiento específico de bandas correspondientes a los 14,22,27-29 y 37-38 kDa. Las bandas de 37-38 y 27-29 kDa destacaron por su sensibilidad y frecuencia, identificadas por el 90 por ciento y 100 por ciento de los infectados, respectivamente. Con el antígeno semipurificado, se evidenció una banda polipeptídica de 28-30 kDa, reconocida por todos los sueros con fasciolosis. Los resultados demuestran, por un lado, la existencia de diversas fracciones polipeptídicas que potencialmente pueden ser promisorias en el inmunodiagnóstico de fasciolosis bovina