Vet World Vol.14 May-2021 Article-24
Research Article
Veterinary World, 14(5): 1247-1257
https://doi.org/10.14202/vetworld.2021.1247-1257
Exogenous bovine somatotropin and mist-fan cooling synergistically promote the intramammary glucose transport for lactose synthesis in crossbred Holstein cows in the tropics
2. Academic of Science, Royal Society of Thailand, Bangkok, Thailand.
3. Queen Saovabha Memorial Institute, The Thai Red Cross Society, Bangkok 10330, Thailand.
4. Department of Biology, Faculty of Science, Mahidol University, Bangkok, Thailand.
5. Department of Animal Husbandry, Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand.
Background and Aim: Milk synthesis by the mammary gland is negatively influenced in part by high ambient temperature (AT). This study aimed to clarify the pathway of intramammary glucose utilization involved in mediating lactose synthesis during treatment with somatotropin under housing with misters and fans.
Materials and Methods: A single subcutaneous injection of 500 mg of recombinant bovine somatotropin (rbST) was administered 3 times once every 14 days to 87.5% crossbred Holstein cattle in early-/mid-/late lactation, under housing in a normal shaded barn and in a shaded barn with a mist-fan cooling system.
Results: The milk yields of the cooled cows tended to increase compared with those of uncooled cows and exhibited more potentiated effects in response to rbST treatment, coinciding with increases in mammary plasma flow and glucose uptake, but not in the mammary extraction of glucose. Treatment with rbST in the cooled cows resulted in a greater increase in the milk glucose concentration and a greater decrease in the milk glucose-6-phosphate concentration at all stages of lactation.
Conclusion: rbST treatment exerted its galactopoietic action more by local intramammary factors than by other extramammary factors at a low AT and the synergistic effect between rbST treatment and low AT increased the availability of intramammary glucose transport in activating the process of lactose synthesis. Keywords: crossbred Holstein cattle, lactose, milk glucose, milk glucose-6-phosphate, mist-fans cooling, recombinant bovine somatotropin.
Keywords: crossbred Holstein cattle, lactose, milk glucose, milk glucose-6-phosphate, mist-fans cooling, recombinant bovine somatotropin.
How to cite this article: Chaiyabutr N, Sitprija S, Chanpongsang S, Thammacharoen S (2021) Exogenous bovine somatotropin and mist-fan cooling synergistically promote the intramammary glucose transport for lactose synthesis in crossbred Holstein cows in the tropics, Veterinary World, 14(5): 1247-1257.
Received: 28-01-2021 Accepted: 08-04-2021 Published online: 21-05-2021
Corresponding author: Narongsak Chaiyabutr E-mail: narongsak.c@chula.ac.th
DOI: 10.14202/vetworld.2021.1247-1257
Copyright: Chaiyabutr, et al. This article is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http:// creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.