Click on “Download PDF” for the PDF version or on the title for the HTML version.
If you are not an ASABE member or if your employer has not arranged for access to the full-text, Click here for options.
Effect of the Cooling Environment on Dry Matter Intake of Diets of Tropical Roughage and their Mixtures, on Milk Production of Holstein Cows in Freestall
Published by the American Society of Agricultural and Biological Engineers, St. Joseph, Michigan www.asabe.orgCitation: Sixth International Dairy Housing Conference Proceeding, 16-18 June 2007, (Minneapolis, Minnesota) (Electronic Only) 701P0507e.(doi:10.13031/2013.22787)
Authors: Fabio Prudencio de Campos, Patrícia Sarmento , Soraia Vanessa Matarazzo, Juliana Rodrigues Pozzi Arcaro, Luiz Gustavo Nussio, Wilson Roberto Soares Mattos, Cristina Dib Corsi, Marcos Rogério Gasqui da Conceicao, Daniela Martins
Keywords: Environment, physiological parameters, nutrition, roughages, heat stress, milk production, Temperature Humidity Index
The quality of diet is not the only responsive factor for increase milk production in cows; there are also the environmental and genetic factors that interact to affect positively or negatively influence animal performance. The trial aimed to evaluate the productive performance of cows submitted to diet based on roughages and concentrates with different energy densities, under different environmental conditions, with and without fans plus misting (FM), to predict the main factors that interfere with in the production system. Eight lactating Holstein cows, with average weight of 550 kg, were assigned in 8x8 Latin square, with periods of 20d: 9d of collection of data. Significant difference by treatments was not observed for either dry matter intake (DMI), with values from 19.2 to 22.4kg DM/day or for milk production (MP), with values from 21.8 to 23.2kg/day, corrected for fat. When using FM the point of maximum DMI (pm) was at 74.7 THI. Without using FM, the smallest DMI happened when the least point was THI of 74.7 (P<.05). When DMI was related to MP the effect was linear and increasing, independently from the use of FM. Analyzing the MP as a function of THI, it is verified that with the use of FM there was pm at THI of 76.1, and without the use there was a low point at THI of 76.0. The physiological parameters (PP) were evidenced by linear and increasing results of the skin temperature (32.1 to 35.0oC) with the increase of THI (71.8 to 76.6). The linear and increasing effects for rectal temperature (38.2 to 38.7oC) and respiratory frequency (38.9 to 65.3 mov/min) as a function of the increase of THI were also verified. The use of FM, depending on the installation type, on the period of the year, will affect more the PP of the animal than the MP in our regional conditions.(Download PDF) (Export to EndNotes)