Replacement of Corn for Cassava Meal (Manihot esculenta, Crantz) in the Holstein Calves Diets: 1. Performance and Blood Parameters

[摘要] - The objective of this project was to evaluate the effects of different replacement levels of corn for cassava meal (0, 25, 50, 75, and 100%, dry matter basis) on the dry matter intake and feed:gain ratio, daily weight gain and levels of blood hematocrit, glucose and urea. Thirty five intact Holstein calves, averaging 80 days old and initial live weight of 80 kg, were allotted to a randomized block design and fed concentrate, ad libitum, to reach the intake of 4 kg/day. Tifton 85 bermudagrass was fed as roughage. The final average weight was of 164 kg. The dry matter intake showed a linear behavior as the replacement levels increased. The feed:gain ratio was not affected by the replacement levels. The daily weight gain for the two first periods of 28 days (period 1 and 2, respectively) reduced as the replacement levels increased, but they were not affected in the last 28 days period (period 3), and the respective values ranged from 0.93 to 0.68, 1.10 to 0.89, and 1.09 kg/day. Levels of hematocrit, glucose and urea were not affected by the replacement of corn for cassava meal.

[学科分类] 兽医学

[关键词] calves;cassava;feed:gain ratio;intake;plasma;weight gain     IntroduçãoA criação dos machos de plantéis leiteiros para abate precoce é viável;mas depende dos preços de mercado