During growth, central venous, right ventricular, pulmonary arterial, Pulmonary capillary wedge, and systemic arterial pressures, heart rate, and cardiac Output were repeatedly measured in 41 Friesian calves, considered as having conventional muscular conformation, and in 19 Belgian White and Blue double-muscled calves. A total of 123 and 70 recordings were collected in conventional and double-muscled calves, respectively. These circulatory indices were calculated: stroke volume, cardiac and stroke indices, pulmonary and systemic pulse pressures, pulmonary and systemic vascular resistance indices, and right and left ventricular work indices. Results indicated that systemic arterial and pulse pressures, as well as cardiac output, stroke volume, cardiac and stroke indices, and right and left ventricular work indices were significantly (P less than or equal to 0.05 to 0.001) lower but, in contrast, pulmonary and systemic vascular resistance indices were significantly (P less than or equal to 0.001) higher in double-muscled than in conventional calves. Right-sided vascular pressures and heart rate were similar in the 2 groups. These results indicated that global cardiac performance may be considerably poorer in double-muscled calves. Diminished cardiac performance of double-muscled calves appears to be related neither to relative bradycardia nor to reduced ventricular preload. The potential role of increased ventricular afterload or of reduced myocardial contractility in double-muscled cattle should be determined by direct measurements.

The calf was a congenital abnormal stillbirth of Sahiwal breed of zebu cattle, with multiple musculoskeletal defects. It was born to a heifer in its first calving. The calving was normal; however, calf born had multiple anomalies. The body of the calf was flashy just like a rubber balloon filled with water (case of hydropsy). The body was without hairs (hypotrichosis). Skeleton was noncalcified and ribs were cartilaginous. The body was identifiable in three regions: head, thoraxabdomen, and limbs. Morphologically limbs were developed but were quite short in length with well-developed hoof. There was one eye like structure just above the mouth (case of cyclopia). The tongue was developed and was protruded from mouth. There was one additional structure on the head, looked like outgrowth of muscles covered with thin skin, had openings of nostrils on the end. In autopsy abdominal body cavity was found filled with fluid. The visceral organ seemed normal. It was identified as female; however, ovaries and genital tract could not be traced and examined. It was the first calving of its dam with the complete gestation period of 287 days like a normal period in cattle. Pieces of tissue from lung and blood from the heart and vena cava were collected; however, cultures were found heavily contaminated with bacterial growth. The actual cause of the defects could not be established, might be defects of certain genes responsible for incomplete growth and development.

In the conditions of the Republic of Belarus there was realized a morphological analysis of pectoral and leg muscles of broiler chickens of cross Cobb-500 in the process of administration of metabolic activator Catosal. Research results showed the positive influence of catosal on the myogenesis: diameter of muscle fiber, the amount of bigger diameter muscles fibers in the first order strand and homogeneity of muscle strands. Under the influence of Catosal preparation there was stated the increasing of the amount of muscle tissue in pectoral and leg parts of chicken carcass. | Приведены данные морфологических исследований грудных и ножных мышц цыплят-бройлеров кросса Кобб-500 при применении активатора метаболизма катозал. Установлено, что катозал активизирует миогенез за счет увеличения диаметра мышечных волокон, содержания в пучках первого порядка мышечных волокон большей толщины, а также большей однородности мышечных пусков. Под действием препарата происходит увеличение содержания мышечной ткани как в грудной части тушки, так и в окороках.