Inclusion of organic acids salts or sodium monensin in the starter feed and its effects on rumen development and performance of dairy calves

Author(s)

Lucas Silveira Ferreira

• Document type: Master's Dissertation
• Press: Piracicaba.
• Institution: Universidade de São Paulo (USP). Escola Superior de Agricultura Luiz de Queiroz (ESALA/BC)
• Defense date: 2008-01-17

Examining board members

Carla Maris Machado Bittar; Wilson Roberto Soares Mattos; Francisco Palma Rennó

• Advisor: Carla Maris Machado Bittar

Abstract

Two trials were conducted in order to evaluate the effects of the addition of sodium butyrate, sodium monensin or calcium propionate in the starter feed on the performance, blood parameters and ruminal development of dairy calves. In the first experiment, 24 newborn Holstein calves were housed in individual hutches during ten weeks of life, with free access to water, being fed 4 liters of milk per day and starter ad libitum, with coast-cross hay offered only after weaning. The animals were blocked according to weight and date of birth and allocated in one of the treatments, according to the additive included in the starter feed: 1) sodium butyrate (0.15%); 2) sodium monensin (30 ppm); and 3) calcium propionate (0.15%). Animals were weighed and evaluated for whiter height, hearth girth and hip width weekly. From the fourth week of age blood samples were taken for glucose, free fatty acids and ?-hydroxybutyrate concentration determination. No significant differences were observed among treatments for starter or hay intake, and weight gain or live weight (P>0.05). Measurements of whiter height and hearth girth were also not affected by treatments (P> 0.05); however, measures of hip width of the animals were smaller for treatment with addition of calcium propionate (P<0.05). Plasma concentrations of glucose, free fatty acids and ?-hydroxybutyrate were not affected by treatment (P>0.05). There was significant effect of age (P<0.0001) for the plasma concentration of glucose, with reduction as animals aged. In the second experiment, 15 male newborns Holstein calves, receiving the same nutritional management, were ruminally fistulated and housed in individual pens during ten weeks of life. From the fourth week of age ruminal samples were taken weekly for the determination of pH, short-chain fatty acids (SCFA) and ammonia-N concentration. Blood samples were also taken weekly for glucose determination. By completing ten weeks of age, animals were slaughtered for forestomach growth and papillae development evaluation. No significant differences were observed among treatments for starter intake as well as for animal performance (P>0.05). The ruminal pH was significantly affected (P<0.05) by treatments and by sampling time. Concentrations of total SCFA and individual SCFA were not affected by treatments (P<0.05). Plasma concentrations of glucose were affected by treatments (P<0.05). The total forestomach weight, the average weight of each compartment and the maximum capacity of reticulum-rumen were not affected by treatments, as well as the parameters for ruminal epithelium development. The additives included in the starter feed were equally effective as regard to its effects on animal performance and rumen development of milk-fed dairy calves. (AU)