@article{Avendano_Aguilar-Quiñonez_Joseph_Macías-Cruz_Guerra-Liera_Alvarez-Almora_Correa-Calderón_Wittayakun_2021, title={Holstein steers grazing two Bermudagrass varieties in hot and dry summer: forage quality and physiological responses of steers}, volume={2}, url={https://ph02.tci-thaijo.org/index.php/JSAT/article/view/244751}, abstractNote={<p>The objective was to evaluate the forage quality of two varieties of Bermudagrass and some physiological traits of Holstein steers during two grazing periods in summer in an arid zone. Twenty-four Holstein steers (BW=200 ± 5 kg), 20 intact animals and 4 with rumen cannulas were randomly assigned for grazing to the Bermudagrass varieties Cross 1 (BC1, n=12) and Giant (BG, n=12) in two consecutive periods (P1 and P2) during summer-fall season in northwestern México. Based on THI estimation, climate in P1 was considered as severe heat stress and P2 as moderate heat stress. Levels of CP and ash were higher (P˂0.05) in BG during P2. Contents of NFD, AFD, and hemicellulose were higher (P˂0.01) in BG and P2 than BC1 and P1, respectively. Only fat content was higher (P˂0.05) in BC1 than BG. The <em>in vitro</em> digestibility of dry and organic matters showed no differences (P>0.05) between varieties or periods. Respiration frequency and all body surface temperatures were higher during the first grazing period and at the afternoon, which agrees with the hottest grazing period and time of day. In conclusion, climatic conditions of the site of the study along with a poor quality of Giant and Cross 1 Bermudagrass varieties under grazing conditions, make the nutritional supplement recommended to reach satisfactory results for growing cattle.</p>}, number={2}, journal={Journal of Science and Agricultural Technology}, author={Avendano, Leonel and Aguilar-Quiñonez, José Antonio and Joseph, Marlene and Macías-Cruz, Ulises and Guerra-Liera, Juan Eulogio and Alvarez-Almora, Enrique and Correa-Calderón, Abelardo and Wittayakun, Suntorn}, year={2021}, month={Nov.}, pages={32–42} }