Growth, development and some indices of the nitrogen metabolism in replacement Biac-and-White heifers under various growing system

• Published in: Malawi medical journal no. 3; pp. 21 - 29
• Main Author: Zelenina, O. V., Russian State Agrarian Univ., Kaluga Campus (Russian Federation)
• Format: Journal Article
• Language: Russian
• Published: 2010
• Subjects: ANIMAL HUSBANDRY; DIGESTIBILIDAD; DIGESTIBILITE; DIGESTIBILITY; ELEVAGE; FEEDING LEVEL; GANADERIA; GENISSE; HEIFERS; http://www.fao.org/aos/agrovoc#c_16128; http://www.fao.org/aos/agrovoc#c_2266; http://www.fao.org/aos/agrovoc#c_3535; http://www.fao.org/aos/agrovoc#c_5274; http://www.fao.org/aos/agrovoc#c_8532; NIVEAU D'ALIMENTATION; NIVEL ALIMENTICIO; NOVILLA; NUTRIENTES; NUTRIENTS; SUBSTANCE NUTRITIVE
• ISSN: 1995-7262; 1995-7270

The trial was performed on three groups of replacement heifer, 16-18 heifer each, fed ration with level of nutrition at 10-15% above the norms (1 group), at 5-6% above the norms (II gr.) or at recommended level of nutrition (III gr.). By the time of the first insemination at the age of 12 mo the heifers of I group have reached LW of 343 kg, of II group at 14 mo - 350 kg and that of III group at 16 mo - 371 kg. The data of exterior measurements has shown that heifers of I group in most cases surpassed the contemporaries in II and III groups (P0.05). Balance experiences haven't revealed any significant differences in digestibility of nutrients. Free amino acids concentration in blood plasma in heifers of I gr. was lower in comparison with II and III grs. (P0.05); in I gr. it was somewhat lower compared to II and III grs. (P0,05). So, the intensive technology allows to shorten the period of growing of replacement heifers, it saves forages, reduces work expenses, but reduces to some extent the first lactation milk yield