Advanced search
Start date
Betweenand


Lactation peak, persistency and mammary apoptosis in Saanen goats: alterations caused by stress

Full text
Author(s):
Ana Paula Rodrigues Gaiato
Total Authors: 1
Document type: Master's Dissertation
Press: Pirassununga.
Institution: Universidade de São Paulo (USP). Faculdade de Zootecnica e Engenharia de Alimentos (FZE/BT)
Defense date:
Examining board members:
João Alberto Negrão; Mariza Pires de Melo; Marco Aurélio de Felicio Porcionato
Advisor: João Alberto Negrão
Abstract

The selection of productive animals and milk quality improvement are the main goals of goat breeders. According to the hypothesis that stress can intensify the apoptosis process during lactation, the purpose of this research is to study stress effect through ACTH administration in animals stressed during lactation and submitted to a three day stress period. Twelve first-rate pregnancy Saanen goats were subdivided in two groups and submitted to ACTH and Placebo treatment once every two months. During the experiment, blood and milk samples were collected to measure Somatic Cell Count (SCC), protein, fat and lactose. Cortisol levels, quantity and quality of produced milk and mammary cells apoptosis rate were analyzed. As a result, there were no differences in milk production, protein, fat, lactose and SCC levels between both groups. On the other hand, animals who received ACTH obtained cortisol peaks, differently than those who received Placebo. Despite cortisol production, the quality and quantity of produced milk did not changed. Concluding, a short stress period does not impact on the goat milk production. (AU)