English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Cattle farming, as one of the most important branches of livestock production, has long been confronted with the chronic problem of the decline in reproductive performances. In 2005, the number of cattle around the world amounted to about 1,370,000,000 heads of cattle, while in 2012 this number was just over a billion, which indicates the importance of applying different reproductive protocols in order to increase production. Heat stress leads to disorders of the physiological and reproductive processes, as the rise in body temperature caused by heat stress has direct negative consequences on numerous cell functions. The study included a total of 54 Holstein- Friesian cows, 28 experimental and 26 control cows from PD Butmir farm with 5 lactations on average. Hormone protocols for estrus and ovulation were used in June and July 2013. Cows in the experimental group were subjected to a Presynch + 5dCoS2 protocol. Cows that did not conceive after this protocol were immediately subjected to resynchronization with Cosynch -72 protocol. The success rate of the Presynch + 5dCoS2 protocol was 19%, while in the case of Cosynch 72 it was 33%, which was statistically significant (p <0,05). The first presynchronization and synchronization protocol (5dCoS2) did not significantly help to improve the conception rate after the first insemination postpartum, but it is evident that they had a positive effect on another protocol (COS72) in the form of reduction in embryonic mortality in the summer months when embryonic loss is the greatest. The COS72 protocol provides satisfactory results in the summer, but good fitness and health management, as well as heat stress reduction in accordance with the location and farm design are the preconditions for a successful estrus and ovulation synchronization program prior to artificial insemination.

SUCCESS OF PROTOCOLS FOR SYNCHRONIZATION OF ESTRUS AND OVULATION IN DAIRY COWS IN SUMMER