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The article presents the results of determining morphometric indicators, biological usefulness, physico-chemical properties and technological features of the longest back muscle of Red steppe (group I), Simmental (group II) and Kazakh white-headed (group III) breeds under intensive cultivation. The obtained data were processed by the method of variation statistics according to N.A. Plokhinsky with the determination of the reliability of the indicators using the Student's criterion. It was found that Kazakh white–headed bulls surpassed their peers of the Red steppe and Simmental breeds in depth of the longest back muscle by 11 mm (22.45%) and 8 mm (15.38%), respectively, in width – by 7 mm (8.24%) and 4 mm (4.55%), the cross-sectional area - by 13.63 cm2 (33.53%) and 10.47 cm2 (23.90%). The muscle tissue of Kazakh white-headed bulls was distinguished by a higher biological value. At the same time, the content of the essential amino acid tryptophan in their muscle tissue was 360.35 mg%, the value of the protein quality index was 5.97 units. In the Red Steppe and Simmental bull calves, the value of the analyzed indicators was at the level of 350.02 mg%, 352.40 mg% and 5.62 units and 5.70 units. The advantage of meat products of Kazakh white-headed bulls in terms of moisture capacity was noted. At the same time, the muscle tissue of the red steppe bulls was characterized by a darker color

https://orcid.org/0000-0001-9241-9228Аннотация. Скотоводство является важным источником получения говядины. Основу откормочного контингента составляют бычки и бычки-кастраты. В то же время сверхремонтные тёлки после интенсивного выращивания и откорма могут стать дополнительным резервом получения высококачественной говядины. Цель исследования -установить влияние скрещивания чёрнопёстрой и голштинской пород на выход съедобной части туши и её сортового состава у тёлок разных генотипов. При этом в 18-месячном возрасте был проведён контрольный убой по 3 тёлки из каждой группы: I -чёрно-пёстрая порода, II -½ голштин×½ чёрно-пёстрая, III -¾ голштин×¼ чёрно-пёстрая. После 24-часовой выдержки в холодильной камере при температуре 0±4 ℃ была проведена обвалка правых полутуш, жиловка и сортировка мякоти по колбасной классификации. В ходе проведения исследования установлено проявление эффекта скрещивания у помесей II и III групп по показателям, характеризующим качество мясной продукции. Так, тёлки I группы уступали аналогу II и III групп по массе съедобной части туши соответственно на 11,20 кг (6,85 %) и 16,68 кг (10,21 %), индексу мясности -на 4,28 % и 5,48 %, выходу мякоти -на 100 кг, предубойной живой массы -на 2,08 % и 2,65 %, соотношению съедобных частей туши и несъедобных -на 5,98 % и 8,55 %. Скрещивание чёрно-пёстрого скота с голштинами способствовало повышению выхода мяса высшего и I сортов при лидирующем положении помесей второго поколения по голштинам III группы.

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The article describes the method for determining the optimal angular velocity and the number of turns of the generator winding on permanent magnets powered by a wind turbine operating in specific operating conditions according to the wind speed regime. The optimization criterion is the maximum potential of energy that can be used to charge the battery. The permissible power of the generator and wind turbine, current and battery charging voltage are accepted as limiting factors. The restriction is provided by connecting a ballast resistor to the generator output. The power developed by the turbine is determined taking into account the wind energy utilization factor, which depends on the angular velocity of its shaft and wind speed. Two variants of power limitation are compared: by limiting the angular velocity by aerodynamic means and by stopping the wind turbine. The return of energy to charging in both cases is determined taking into account the distribution of wind speeds, obeying the Weibull probability distribution law. As an example, the calculation of the possible annual power generation for charging a battery with a capacity of 200 A∙h with a voltage of 24 volts from a synchron generator with a number of poles of 48 driven by a wind turbine with a radius of 2 meters, operating in an area with an average wind speed of 5 m/s. The calculation shows that for the parameters and operating conditions of the electrical installation used in the example, the maximum annual energy output (3.3 × 103 kWh) is observed at optimal 11 turns of the winding at each of the poles of the generator. The deviation of the number of turns from the optimal one in both directions by 2 times leads, with the same dimensions of the wind turbine, to a decrease in annual energy output by 3...5 times, which is a clear proof of the need to carry out such a calculation for each specific wind turbine.