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The cuniculture has become an important source of animal protein in many countries. The coccidiosis is the most common parasitic disease of the rabbits and is responsible for severe economic losses for breeders. Rabbit coccidiosis is caused by 11 species of the genus Eimeria, which vary considerably in terms of their morphology and pathogenicity. The aim of this study was to evaluate prevalence of Eimeria spp in backyard farms from Mexico during annual seasons. Cross-sectional sampling was performed in young rabbits (20 to 60 days of age) with diarrhea history, from three municipalities located in the south-east region from the State of Mexico. Flotation and Mc Master techniques were performed; oocysts were sporulated and measured for morphometric identification. The highest prevalence of Eimeria was found in autumn (75%) in Temamatla and winter (88%) in Amecameca, being the lower prevalence in spring (5%) in Temamatla. In terms of their pathogenicity  E. itestinalis was the more pathogen found in this study, being the annual prevalence of 11.3%. It is important to continue with studies of prevalence in other regions of the State of Mexico, in order to understand the pattern of presentation and distribution of the Eimeria spp infection.

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Parasitic agents, such as helminths, are the most important biotic factors affecting aquaculture, and the fluke Centrocestus formosanus is considered to be highly pathogenic in various fish species. There have been efforts to control this parasite with chemical helminthicides, but these efforts have had unsuccessful results. We evaluated the anthelmintic effect of 37 strains of Bacillus thuringiensis against C. formosanus metacercariae in vitro using two concentrations of total protein, and only six strains produced high mortality. The virulence (CL50) on matacercariae of three strains was obtained: the GP308, GP526, and ME1 strains exhibited a LC50 of 146.2 µg/mL, 289.2 µg/mL, and 1721.9 µg/mL, respectively. Additionally, these six B. thuringiensis strains were evaluated against the cercariae of C. formosanus; the LC50 obtained from the GP526 strain with solubilized protein was 83.8 µg/mL, and it could be considered as an alternative control of the metacercariae and cercariae of this parasite in the productivity systems of ornamental fishes.

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Two groups were formed in order to evaluate the effect of an obesogenic diet on body and liver weight, body fat accumulation and the histometric characteristics of liver and testicles of New Zealand rabbits during the peripuberal period. One group received a standard farm diet and the other received a standard farm diet with canola oil added. During the study, weight of both groups was recorded. At the end of the study, the rabbits were euthanized and liver, testicles, and visceral, scapular and scrotal fat were weighed. Tissue samples were obtained from liver and testicles to carry out histometric analysis. Body weight, body mass index, liver and visceral fat weight were significantly different (P<0.01) in the obesogenic diet when compared to the control group. Notwithstanding, there were no significant differences between both groups in testicular weight, and scapular and scrotal fat (P>0.01). Histometry of the liver of the obesogenic diet group showed the greater total area and greater nucleus area of hepatocytes in the square lobe, right lobe and left lobe medial segment (P<0.01). Histometry of both testicles of individuals from the obesogenic diet group had a greater germinal epithelial thickness and intertubular intersticium (P<0.01). It is concluded that New Zealand male rabbits that received an obesogenic diet during 12 weeks had a higher liver and body weight, as well as, an important increased visceral fat. Furthermore, said diet caused histometric changes in liver and testicles. This set confirms that the domestic rabbit is a good model for the study of the body fat accumulation process associated to the consumption of an obesogenic diet and its effects on liver and testicles.

Con el propósito de evaluar el efecto de una dieta obesogénica sobre el peso corporal, hepático, acumulo de grasa corporal y las características histométricas del hígado y testículo de conejos Nueva Zelanda durante el período peripuberal, se formaron dos grupos; a uno se le proporcionó una dieta estándar de granja y el otro recibió una dieta estándar de granja adicionada con aceite de canola. Durante el estudio se registró el peso corporal de ambos grupos. Al final del estudio los conejos fueron eutanasiados y se pesó el hígado, testículos, la grasa visceral, escapular y escrotal. Se obtuvieron muestras de tejido hepático y testicular para realizar el análisis histométrico. El grupo con dieta obesogénica presentó diferencias significativas con respecto al grupo testigo, en las variables: peso corporal, índice de masa corporal, peso del hígado y de la grasa visceral (P<0,01). Por otra parte, no hubo diferencias significativas entre ambos grupos para las variables: peso de testículos, grasa escapular y escrotal (P>0,01). En la histometría del hígado el grupo con la dieta obesogénica presentó mayor área total y mayor área del núcleo de los hepatocitos en el lóbulo cuadrado, lóbulo derecho y lóbulo izquierdo segmento medial (P<0,01). En la histometría de ambos testículos del grupo con la dieta obesogénica se encontró mayor grosor del epitelio germinal y perímetro del intersticio intertubular (P<0,01). Se concluye que los conejos Nueva Zelanda machos que recibieron una dieta obesogénica durante 12 semanas presentaron mayor peso corporal, hepático y aumento de la grasa visceral. Además, presentaron cambios histométricos en hígado y testículo. Estos resultados en conjunto confirman que el conejo doméstico es un buen modelo para el estudio del proceso de acumulo de grasa corporal asociado al consumo de una dieta obesogénica y de sus efectos en el hígado y testículos.

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BACKGROUND: The mite Psoroptes cuniculi is a common worldwide ectoparasite and the most frequently found in rabbit farms. It causes significant economic losses on commercial rabbit breeding associated with poor leather quality, reduced conception rates, weight loss, poor growth and death. Several strategies have been proposed for the treatment of mange caused by this mite, ranging from the use of acaricides, entomopathogenic fungi, essential oils and vaccines. However, therapy and control of both human scabies and animal mange are still based mainly on the use of drugs and chemicals such as ivermectin, which involves disadvantages including genotoxic and cytotoxic effects, resistance and environmental damage. Bacillus thuringiensis is a bacterium, innocuous for human being, domestic animals and plants that produces highly biodegradable proteins, and has been used worldwide for biological control. The aim of this work was to find an alternative treatment based on biological control for scabies caused by Psoroptes cuniculi, using protein extracts from strains of Bacillus thuringiensis. METHODS: P. cuniculi mites were obtained from naturally infected New Zealand rabbits, and different doses of protein from B. thuringiensis were added to the mites. We measured mortality and obtained the median lethal concentration and median lethal times. For histological analysis, the mites were fixed in 10% formalin, processed according to the paraffin embedded tissue technique. Sections were stained with hematoxylin-eosin to observe the general histological structure. RESULTS: We report here for the first time evidence about the in vitro acaricidal effect caused by the strain GP532 of B. thuringiensis on the mite Psoroptes cuniculi, with an LC50 of 1.3 mg/ml and a LT50 of 68 h. Histological alterations caused by B. thuringiensis on this mite, included the presence of dilated intercellular spaces in the basal membrane, membrane detachment of the peritrophic matrix and morphological alterations in columnar cells of the intestine. CONCLUSIONS: Since this mite is an obligate ectoparasite that affects rabbits, goats, horses, cows and sheep, B. thuringiensis protein extracts are proposed as a potential treatment for biological control of mange in farm animals.

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La citología vaginal puede usarse para caracterizar estados del ciclo reproductivo de la hembra. Sin embargo, no ha sido validada en ovinos de pelo, y ofrece resultados inexactos debido a interpretaciones subjetivas. El objetivo del presente trabajo es tipificar las características morfológicas y morfométricas de las células epiteliales de la vagina durante el ciclo estral en ovinos de pelo. Cinco borregas Santa Cruz se sincronizaron con esponjas intravaginales. Desde el día del 1er celo posterior al retiro de la esponja y hasta el siguiente celo, se obtuvieron muestras diarias del epitelio vaginal de cada oveja, y se cuantificó el número de células parabasales, intermedias y superficiales, y se midió la longitud, perímetro y área de citoplasma y núcleo de cada una. Los resultados muestran que las células superficiales incrementan (P<0,05) durante el estro en comparación con el diestro. En contraste, el número de células parabasales e intermedias es mayor (P<0,05) durante el diestro que en el estro. Las células más grandes (36,11+/-0,38 µm) y núcleos más pequeños (8,46+/-0,12 µm) se encontraron durante el estro, independientemente del tipo de célula, mientras que citoplasmas más pequeños (26,72+/-0,11 µm) y núcleos más grandes (10,48+/-0,02 µm) se observaron durante el diestro. Se concluye que la morfología de las células epiteliales de la vagina de la oveja de pelo coincide con las variaciones encontradas en otras hembras, y que el tamaño de citoplasmas y núcleos presenta un patrón cíclico que puede utilizarse para determinar de manera objetiva la etapa del ciclo estral de la oveja.

Vaginal cytology can be used to characterize stages of the reproductive cycle of the female. However, it has not been validated in hair sheep, and generates inaccurate results due to subjective interpretations. Thus, the purpose of the present work is to typify morphologic and morphometric characteristics of the epithelial cells from the vagina during the estrous cycle of hair sheep. Five Saint Croix ewes were synchronized with intravaginal sponges. Day zero of the cycle was considered the day of first estrus after sponge withdrawal. From this day until next estrus, samples from the vaginal epithelium were obtained daily from each ewe. The number of basal, intermediate and superficial cells was quantified, and length, perimeter, and area from cytoplasm and nucleus were obtained. The results show that the number of superficial cells increase (P<0.05) during estrus and decrease during the rest of the cycle. In contrast, the number of basal and intermediate cells showed an inverse pattern. The largest cells (36.11+/-0.38 µm) and smallest nucleuses (8.46+/-0.12 µm) were present during estrus, regardless of the cell type, while the smallest cells (26.72+/-0.11 µm) and larger nucleuses (10.48+/-0.02 µm) were observed during diestrus. It was concluded that citology of the epithelial cells from the vagina of hair ewes is in accord with changes found in other female spices, and that cytoplasm and nucleus sizes display a cyclic pattern that might be used to objectively determine the specific estrous cycle phase of the ewes.

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The purpose of this study was to analyze the macroscopic morphometry of the ovaries, uterus and vagina in rabbit does in the first, second and third parturition at 24 hours post-weaning in order to determine if there are differences between parturitions. Weaning of the litter was performed at 30 days post-partum and 24 hours later the does were euthanized. Right and left ovaries, uterine horns-cervix and vagina were removed, and the length of each one was measured. Significant differences were found in the average of the right ovary length between the first group with respect to second and third parturition group (P 0.05 and P 0.01). Also, left ovary length was different between the first and second with respect to third parturition group (P <0.001). Average total ovary length increased significantly as the number of parturitions increased in second and third parturition groups (P 0.01 and P0.001). The weight of the left and right ovaries was higher in does in their second and third parturition when compared to those in their first (P 0.5; P 0.01). The average total ovary weight increased significantly as the number of parturitions in second and third parturition groups (P0.001). The length of the left and right uterine horn-cervix of the rabbits after second and third parturition decreased when compared to that of females in their first parturition (P 0.05; P0.001). The average total uterine horns-cervix length decreased significantly as the number of parturitions in second and third parturition groups (P0.001). Furthermore, vagina length in females in their third parturition was greater than that of first and second parturition (P 0.01).The color of the vulva of the majority of females in their first parturition (3/4) was pale pink while. In contrast, the majority of females in their second parturition (3/4) had their vulva intensely red. All of the females (4/4) in the third parturition group had their vulva intensely red...

El propósito de este estudio fue analizar la morfometría macroscópica de los ovarios, útero y vagina en conejas de primero, segundo y tercer parto a las 24 horas post-destete con el propósito de determinar si existen diferencias entre los partos. El destete de la camada se realizó a los 30 días después del parto y 24 horas después fueron eutanasiadas. De cada animal se removieron los ovarios derecho e izquierdo, cuernos-cuello uterinos derecho e izquierdo y la vagina y se midió la longitud de cada uno de los órganos genitales. Se encontraron diferencias significativas en la longitud del ovario derecho entre el grupo de primer parto con respecto al de segundo y tercer parto (P 0,05 y P 0,01). Además, la longitud media de ovario izquierdo fue significativamente diferente entre el grupo de primero y segundo parto con respecto al de tercer parto (P <0,001). La longitud total de los ovarios aumentó con el número de partos y fue mayor en los grupos de segundo y tercer parto (P 0,01 y P 0,001). El peso de los ovarios derecho e izquierdo fue mayor en el grupo de segundo y tercer parto al compararlo con el de primero parto (P 0,5; P 0,01). Por otra parte, el peso total de los ovarios aumentó en los grupos de segundo y tercer parto (P 0,001). La longitud del cuerno-cuello uterino izquierdo y derecho de los grupos de segundo y tercer parto disminuyó al compararlo con el de las hembras de primer parto (P 0,05; P 0,001). La longitud total del cuerno-cuello uterino izquierdo y derecho disminuyó significativamente en las hembras de segundo y tercer parto (P 0,001). La longitud de la vagina de hembras de tercer parto fue mayor que la de primero y segundo parto (P 0,01). El color de la vulva de la mayoría de las hembras de primer parto (3/4) fue rosa pálido. En contraste, la mayoría de las hembras en su segundo parto (3/4) presentaron vulva de color rojo intenso. Todas las hembras del grupo de tercer parto (4/4) presentaron vulva de color rojo intenso...

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Bacillus thuringiensis is a gram-positive soil-dwelling bacterium that is commonly used as a biological pesticide. This bacterium may also be used for biological control of helminth parasites in domestic animals. In this study, we evaluated the possible ovicidal and cestocidal effects of a total protein extract of B. thuringiensis native strains on the zoonotic cestode parasite of dogs, Dipylidium caninum (D. caninum). Dose and time response curves were determined by coincubating B. thuringiensis proteins at concentration ranging from 100 to 1000 µ g/mL along with 4000 egg capsules of D. caninum. Egg viability was evaluated using the trypan blue exclusion test. The lethal concentration of toxins on eggs was 600 µ g/ml, and the best incubation time to produce this effect was 3 h. In the adult stage, the motility and the thickness of the tegument were used as indicators of damage. The motility was inhibited by 100% after 8 hours of culture compared to the control group, while the thickness of the cestode was reduced by 34%. Conclusively, proteins of the strain GP526 of B. thuringiensis directly act upon D. caninum showing ovicidal and cestocidal effects. Thus, B. thuringiensis is proposed as a potential biological control agent against this zoonosis.

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To evaluate the level of stress induced by the tongue inspection method during cysticercosis diagnosis in pigs at 60 and 90 kg, 27 animals were assigned to one of three experimental groups. In the first group (T1), pigs were held with a snout noose. In addition, animals in T2 were subjected to tongue inspection, while in T0, none of the procedures described above were performed. Resistance to be handled and serum cortisol concentration were higher (P < 0.05) than those from T0 in T1 and T2 groups, for 60- and 90-kg pigs. Time to return to the feeder observed the same pattern than previous variables in 60-kg pigs, but T1 and T0 were similar (P > 0.05) for the heavier animals. T2 did not build up a significant amount of stress with respect to T1, where only more (P > 0.05) vocalizations were emitted by 90-kg pigs. It was concluded that the use of snout noose induces major changes in some behavioral and physiological measures of stress in swine, while the opening of the mouth including tongue inspection does not contribute significantly to this effect.

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