Authors: H. Levit§†, S. Pinto*#, E. Gershon, A. K. Elazary†*, V. Bloch§*, Y. Ben Meir†‡, J. Miron‡, I. Halachmi§ - Date: May 29, 2018
The immense metabolic demand of high yielding cows is constantly requires disposing (by panting, sweating and vasodilatation) large amount of metabolic heat. Inability to do so causes heat stress expressed in animal suffering and deteriorates production and reproduction. In many arid and semi-arid zones, fans and water sprinklers are used in barn, in forced cooling yards and/or in the feeding lane to help the cows to get rid of excessive heat.
It is common to activate the cooling management by surrounding temperature-humidity index (THI) measurements and not by real time body temperature measurements of the cow that might be different (due to production level, body condition, gynecologic status, herd genetic variance) in response to heat stress etc.
Real-time temperature can now be measured using reticulorumen bolus (SmaXtec). The current study, was dedicated to develop a model that calibrates on line the cow body temperature measured by boluses in the reticulorumen and use it to improve cooling regime, milk production and welfare of the cows. A total of 30 lactating cows were randomly assigned in pairs to one of two cooling regime groups fed the same TMR: Control group of 15 cows that received the common evaporative cooling methods used in farms (time based evaporative cooling 5 times /d), while the experimental group received the sensor based cooling regime, that was changed every week according to the cow's body temperature measured by reticulorumen boluses.
The experimental cows showed similar milk yield but higher milk fat (3.65 vs 3.43%), milk protein (3.23 vs 3.13%), Energy corrected milk (ECM , 42.84 vs 41.48), 4% fat corrected milk; (FCM, 42.76 vs 41.34) and lower average body temperatures (38.6°C). The sensor base cooling regime found to be an effective tool to detect and ease heat stress in high producing dairy cows under summer heat load in arid and semi-arid zones.
Corresponding author: Harel Levit, Precision Livestock Farming (PLF) Lab. Institute of Agricultural Engineering, Agricultural Research Organization – ARO, The Volcani Center, 68 HaMaccabim Road, Rishon LeZion 7505101, Israel.
Department of Animal Sciences, The Robert H. Smith Faculty of Agriculture, Food, and Environment, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 76100, Israel