Histomorphometric study of the anterior latissimus dorsi muscle and evaluation of enzymatic markers of broilers affected with dorsal cranial myopathy.

Dorsal cranial myopathy (DCM), which affects the anterior latissimus dorsi (ALD) muscles of commercial broilers, is of unknown etiology, and it represents up to 6% of the partial condemnations in Brazilian slaughterhouses. This study was performed to achieve histomorphometric characterizations of the ALD muscles from male Cobb 500 broilers slaughtered at either 35 d or 42 d and to evaluate the effects of DCM on the enzymatic markers aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatine kinase (CK), and lactate dehydrogenase (LDH) and on uric acid and creatinine metabolites. Blood samples (1.5 to 3 mL) and ALD muscle fragments were collected from each carcass, all of which were processed in a commercial inline processing system. For each age, twelve macroscopically normal animals and twelve animals found to exhibit DCM were randomly selected for histomorphometric evaluation and analysis of serologic profiles. Microscopic evaluations demonstrated that the muscle fibers of those with DCM exhibited a strong presence of multifocal regenerative myodegeneration as well as a substitution of muscle tissue with connective tissue (P < 0.001) through fibrosis, thus characterizing the chronicity and hardness of the affected muscle. It is suggested that DCM is a localized muscle lesion because the detected serum levels of CK (P < 0.001), AST (P < 0.001), ALT (P = 0.01), and LDH (P < 0.001) enzymes were strongly associated with the group affected by DCM. Additional studies are needed to gain an understanding of this myopathy because it is an emerging problem in the poultry industry. In addition, it is related to DCM lesions in fast-growing broilers with the greatest slaughter weights.

Relación entre el tipo de fibra muscular esquelética del miembro posterior del caprino (Capra hircus) y su capacidad oxidativa y glicolítica / Relationship between skeletical muscular fiber type of the caprine (Capra hircus) hindlimb and the oxidative and glicolitic capacity

Se estudiaron con técnicas histoquímicas, los músculos de la cadera y el muslo del miembro posterior del caprino en condiciones de manejo semi-intensivo, con la finalidad de conocer la relación entre el tipo de fibra muscular y capacidad oxidativa y glicolítica de las mismas. Se tomaron muestras in vivo de los músculos gluteobíceps, glúteo medio, glúteo profundo, vasto intermedio, vasto lateral, gastrocnemios, soleo, semimembranoso, semitendinoso y tensor de la fascia lata, en cinco (5) cabras de 21-30 kg de peso. Las muestras se congelaron en isopentano enfriado en nitrógeno líquido. Los cortes se realizaron en un criostato a -20°C, con un espesor de 10 µm. Se utilizaron las técnicas de la Nicotamida Adenina Dinucleotido Deshidrogenada-Diaforasa (NADH-d) para determinar la capacidad oxidativa y la α-Glicero Fosfato Deshidrogenasa (α-GPD), para estudiar la capacidad glicolítica. El músculo vasto intermedio presentó 100 por ciento de fibras tipo I, casi todas de alta capacidad oxidativa. Los músculos glúteos medio y profundo, mostraron alrededor de 45 por ciento fibras tipo I, 22 por ciento de tipo IIa y 33 por ciento tipo IIb; aproximadamente la mitad de sus fibras presentaron alta capacidad oxidativa y entre media y baja capacidad glicolítica. El resto de los músculos tuvo un porcentaje alrededor de 29 por ciento de las fibras tipo I, 31 por ciento del tipo IIa y 40 por ciento del tipo IIb. En estos músculos se determinó un predominio de fibras con alta y mediana capacidad glicolítica.

With technical histochemical were studied, the muscles of the hip and the thigh of the hind limb of the goats under conditions of exploitation semi intensive with the purpose of knowing the relationship between of the different types of fibers and the oxidative and glicoltic capacity. They took samples in vivo of the muscles gluteal biceps, middle gluteal, deep glutea, vastus intermedius, vastus lateral, gastronemius, soleus, semimembranosos, semitendinosus and tensor facialatae in five (5) goats of 21-30 kg of weight. The samples froze in isopentano cooled in liquid nitrogen. The cuts were carried out in a cryostat to -20°C, with a thickness of 10 µm. The Nicotamida Adenosina Dehydrogenize diaphoreses (NADH-d) reactions were used to determine the capacity oxidative and the α-Glycerol Phosphate Dehydrogenize (α-GPD), to study the capacity glicolític. The muscle vast intermission presents 100 percent of fibers type I, almost all of high capacity oxidative. The muscles gluteus half and deep showed around 45 percent fibers type I, 22 type percent IIa and 33 percent type IIb; approximately half of their fibers they presented high capacity oxidative and between stocking and low capacity glicolítica. The rest of the muscles had a percentage around 29 percent of the fibers type I, 31 percent of the type IIa and 40 percent of the type IIb; in them there was a prevalence of fibers with high and medium capacity glicolítica.