Vacas leiteiras mestiças a pasto alimentadas com diferentes suplementos no período de transição seca-águas

Detalhes bibliográficos
Ano de defesa: 2009
Autor(a) principal: MELO, Wellington Samay de lattes
Orientador(a): VÉRAS, Antonia Sherlânea Chaves
Banca de defesa: MELO, Airon Aparecido Silva, GONZAGA NETO, Severino, VÉRAS, Robson Magno Liberal
Tipo de documento: Tese
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Universidade Federal Rural de Pernambuco
Programa de Pós-Graduação: Programa de Pós-Graduação em Zootecnia
Departamento: Departamento de Zootecnia
País: Brasil
Palavras-chave em Português:
Palavras-chave em Inglês:
Área do conhecimento CNPq:
Link de acesso: http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/6927
Resumo: This study evaluated the intake and apparent digestibility of nutrients; production and chemical composition of milk; the additional cost of the supplements; microbial synthesis of nitrogen and rude protein, and their efficiencies; plasma levels of glucose and urea; and excretions of urea in crossbred dairy cows on pasture during the dry-water transition. It was used eight cows (Gyr/Holstein/Brown Swiss) without defined genetic composition, average production of 15 kg/day and average live weight of 500 kg; distributed in two latin squares. The experimental period lasted 60 days (four sub-periods of 15 days). The following treatments were offered: corn silage + concentrate; forage cactus + concentrate, corn silage + soybean meal, and forage cactus + soybean meal. The concentrate was elaborated with 27.75% of rude protein. The pasture area used was 53 ha, with Brachiaria decumbens sp.Predomination. The supplements promote addictive effect on pasture nutrients when they contained corn silage andsubstitutive effect when they contained forage cactus. The supplements containing forage cactus promotes smaller intake of neutral detergent fiber and larger of non-fiber carbohydrate. The apparent digestibility of the neutral detergent fiber and non-fiber carbohydrate differ from the use of forage cactus or corn silage. The use of the supplements containing concentrate elevates the milk production up to 17 kg/day in the drought-waters transition period. The supplements can be used without any damage to milk composition. Economical results suggest flexibilization of the supplements. The use of the supplements balances glucose and urea plasmatic levels, as well as the ureaexcretion in urine and milk. There was similarity in the supplements nitrogen metabolism, consequently, nitrogen and of rude protein microbial synthesis they were similar. The efficiency of synthesis of microbial rude protein in cows receiving supplements on grazing in the drought-waters transition period shows an average of 146,20 g MicRP/Kg TDN.