<abstract xmlns="http://www.w3.org/1999/xhtml"><p>The main objective of this study was to identify the influences of different climatic conditions and cow-related factors on the respiration rate (RR) of lactating dairy cows. Measurements were performed on 84 lactating Holstein Friesian dairy cows (first to eighth lactation) in Brandenburg, Germany. The RR was measured hourly or twice a day with up to three randomly chosen measurement days per week between 0700 h and 1500 h (GMT + 0100 h) by counting right thoraco-abdominal movements of the cows. Simultaneously with RR measurements, cow body postures (standing vs. lying) were documented. Cows’ milk yield and days in milk were recorded daily. The ambient temperature and relative humidity of the barn were recorded every 5 min to calculate the current temperature-humidity index (THI). The data were analyzed for interactions between THI and cow-related factors (body postures and daily milk yield) on RR using a repeated measurement linear mixed model. There was a significant effect of the interaction between current THI category and body postures on RR. The RRs of cows in lying posture in the THI &lt; 68, 68 ≤ THI &lt; 72 and 72 ≤ THI &lt; 80 categories (37, 46 and 53 breaths per minute (bpm), respectively) were greater than those of standing cows in the same THI categories (30, 38 and 45 bpm, respectively). For each additional kilogram of milk produced daily, an increase of 0.23±0.19 bpm in RR was observed. Including cow-related factors may help to prevent uncertainties of RR in heat stress predictions. In practical application, these factors should be included when predicting RR to evaluate heat stress on dairy farms.</p></abstract>

The main objective of this study was to identify the influences of different climatic conditions and cow-related factors on the respiration rate (RR) of lactating dairy cows. Measurements were performed on 84 lactating Holstein Friesian dairy cows (first to eighth lactation) in Brandenburg, Germany. The RR was measured hourly or twice a day with up to three randomly chosen measurement days per week between 0700 h and 1500 h (GMT + 0100 h) by counting right thoraco-abdominal movements of the cows. Simultaneously with RR measurements, cow body postures (standing vs. lying) were documented. Cows’ milk yield and days in milk were recorded daily. The ambient temperature and relative humidity of the barn were recorded every 5 min to calculate the current temperature-humidity index (THI). The data were analyzed for interactions between THI and cow-related factors (body postures and daily milk yield) on RR using a repeated measurement linear mixed model. There was a significant effect of the interaction between current THI category and body postures on RR. The RRs of cows in lying posture in the THI < 68, 68 ≤ THI < 72 and 72 ≤ THI < 80 categories (37, 46 and 53 breaths per minute (bpm), respectively) were greater than those of standing cows in the same THI categories (30, 38 and 45 bpm, respectively). For each additional kilogram of milk produced daily, an increase of 0.23±0.19 bpm in RR was observed. Including cow-related factors may help to prevent uncertainties of RR in heat stress predictions. In practical application, these factors should be included when predicting RR to evaluate heat stress on dairy farms.

Influence of Barn Climate, Body Postures and Milk Yield on the Respiration Rate of Dairy Cows

Department of Engineering for Livestock Management, Leibniz Institute for Agricultural Engineering and Bioeconomy – ATB

Institute of Animal Hygiene and Environmental Health

Faculty of Civil Engineering, Architecture and Environmental Engineering

School of Civil Engineering & Surveying Faculty of Health

Annals of Animal Science

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

The main objective of this study was to identify the influences of different climatic conditions and cow-related factors on the respiration rate (RR) of...

Influence of Barn Climate, Body Postures and Milk Yield on the Respiration Rate of Dairy Cows

Published Online: May 02, 2019

Page range: 469 - 481

Received: Sep 17, 2018

Accepted: Jan 24, 2019

DOI: https://doi.org/10.2478/aoas-2019-0006

Keywords
dairy cow, heat stress, temperature-humidity index, cow-related factors, naturally ventilated barn

© 2019 Severino Pinto et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Influence of Barn Climate, Body Postures and Milk Yield on the Respiration Rate of Dairy Cows

Published Online: May 02, 2019

Page range: 469 - 481

Received: Sep 17, 2018

Accepted: Jan 24, 2019

DOI: https://doi.org/10.2478/aoas-2019-0006

Keywordsdairy cow, heat stress, temperature-humidity index, cow-related factors, naturally ventilated barn

© 2019 Severino Pinto et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
dairy cow, heat stress, temperature-humidity index, cow-related factors, naturally ventilated barn