Modificación de biomarcadores histopatológicos e inmunohistoquímicos en las fibras musculares de cerdos tratados con clenbuterol / Modification of his topathological and immunohistochemical biomarkers in the muscle fibers of swine after clenbuterol exposure

El clenbuterol frecuentemente se ha utilizado de forma ilícita en el engorde del ganado, suponiendo ello un riesgo para la salud pública. La actual normativa prohíbe por tanto su uso en la cría del ganado. En este estudio se utilizaron 14 cerdos distribuidos al azar en dos grupos de estudio (n=7), uno control, y otro expuesto a 1 mg/kg de clenbuterol durante tres meses. Se utilizó el músculo longissimus lumbaris para la determinación de la concentración de clenbuterol, así como para la evaluación de los parámetros inmunohistoquímicos y el análisis estructural y ultraestructural de las fibras. El estudio de los distintos biomarcadores histopatológicos e inmunohistoquímicos de las fibras musculares, tras la exposición de los animales al clenbuterol, indicó la presencia de hipertrofia muscular, miofibrolisis y degeneración zenkeriana, observada tanto por microscopía óptica como electrónica. Mediante la técnica miosina ATP-asa se identificó un tipo de fibra denominada alterada en el grupo tratado que no apareció en el grupo control. Por tanto, se comprueba que el músculo longissimus lumbaris resulta una buena matriz para la investigación de la exposición a largo plazo a este compuesto en cerdos (AU)

Clenbuterol has been frequently used illicitly, causing a risk to public health; the current regulation prohibits its use to put on weight the animals. In our study we have used 14 swines radomly distributed into two groups (n=7): one control group, and another group exposed to 1 mg/kg of clenbuterol during three months. The muscle selected for the research was longissimus lumbaris and it was used for the determination of the concentration of clenbuterol, as well as for the evaluation of the immunohistochemical parameters, and the structural and ultrastructural analysis of the fibers. The study of the different histopathological and immunohistochemical biomarkers of the muscular fibers, after clenbuterol exposure, indicated the presence of muscular hypertrophy, myolysis, and zenkerian degeneration, observed at optic and electronic microscopy. By the use of the miosin ATP-ase technique, it was identified a fiber type denominated altered in the treated group that did not appeared in the control group. Therefore, it was verified that the muscle longissimus lumbaris is a good matrix for the investigation of the long-term exposure to this clenbuterol in swines (AU)

Saliva crystallisation as a means of determining optimal mating time in bitches.

OBJECTIVES: To chart saliva crystallisation patterns throughout pro-oestrus and oestrus in bitches, and to assess their reliability as a tool for optimising the timing of breeding. METHODS: Six beagle bitches with normal reproductive activity were used. Saliva ferning patterns were established during pro-oestrus and oestrus. Vaginal cytology, progesterone (P4) levels and behavioural signs were used to determine the optimum mating time. Receiver operating characteristic (ROC) analysis was performed. RESULTS: Different ferning patterns were scored from 0 to 2. Although variations in saliva crystallisation were noted during the follicular phase of the oestrous cycle in bitches, the test did not prove accurate; test sensitivity was 40.6%, i.e. too low to reliably discriminate the fertile period, while specificity was 86.1%. CLINICAL SIGNIFICANCE: This test could be used to complement other methods of determining the fertile period in bitches, but its potential capacity remains to be demonstrated.

Quantitative study of Leydig cell populations in mice exposed to low doses of cadmium.

Leydig cell morphological changes were evaluated using morphometric and stereological methods in male mice exposed to low doses of cadmium. A possible reversibility of the changes after cadmium withdrawal was also considered. Nuclear morphological parameters and stereological densities of the Leydig cell population were lower in the cadmium-exposed groups than in the control. The withdrawal of cadmium did not lead to any significant recovery of the morphological parameters. Nevertheless, numerical density increased significantly in the withdrawn groups, suggesting that the hyperplasia of interstitial cells could try to relieve morphological damage after cadmium withdrawal.

Echium vulgare and Senecio vulgaris poisoning in fighting bulls.

An unusual case of poisoning by simultaneous ingestion of Echium vulgare L. and Senecio vulgaris L. in a herd of Spanish fighting bulls is described. Ten animals died from a herd of 700 in an area located in Sierra Norte, Seville (Constantina) in Spain. The interest of this case lies both in the breed affected (this is the first report on fighting bulls) and the lack of information about bovine poisoning by these plants in Spain. Animal samples were obtained from October to March. All the dead animals were 1 year old and had grazed at the farm. The diagnosis was made by determining the plant species and studying its distribution in the pastureland, and also by performing blood analysis of the sick animals in addition to an anatomopathological study of the carcasses. Tuberculosis, brucellosis, salmonellosis, IBR/BVD and also the presence of aflatoxins in the forage were all ruled out.