干旱区生态环境知识资源中心(Arid): Effects of heat stress on reproductive efficiency in Holstein dairy cattle in the North African arid region

Arid

DOI	10.1111/rda.13772
	Effects of heat stress on reproductive efficiency in Holstein dairy cattle in the North African arid region
	Djelailia, Hanane; Bouraoui, Rachid; Jemmali, Bayrem; Najar, Taha
通讯作者	Jemmali, B
来源期刊	REPRODUCTION IN DOMESTIC ANIMALS
ISSN	0936-6768
EISSN	1439-0531
出版年	2020
卷号	55 期号:9 页码:1250-1257
英文摘要	This work aims to study the relationship between variations of the Temperature-Humidity Index (THI) and the parameters of reproduction especially the first conception rate (FCR) and to determine the threshold THI value where cows' fertility rate dropped in 12 Holstein dairy herds raised in the arid climatic conditions of Tunisia. THI values were calculated over 22 years (1996-2018), and the mean monthly temperature and relative humidity data were obtained from the Meteorological Institute of Tunisia. A total of 20,396 individual records (Insemination and calving dates) were extracted from the Livestock and Pasturing Office (OEP, Tunisia) with regard to the highest THI before breeding, on the breeding day, and after breeding. Statistical analysis was performed using the GLM procedure of SAS software. Results point to the fact that a summer heat stress exists in southeast Tunisia and lasts for 4 months starting from June until September with THI values fluctuating between 73 +/- 2.38 and 79 +/- 3.01 exceeding, therefore, THI threshold of 72. Increased THI from <= 70 to >= 80 units was associated with drops in conception rate (CR) and fertility rate (FR) of 49% and 45% giving a correlation with the THI of (r = -.72,p < .05) and (r = -.74,p < .05), respectively. When cows were inseminated on extremely hot days (THI >= 80) preceded by cooler temperatures, pregnancy by service (P/AI) was 7% points higher than for other cows that were exposed to high temperatures before breeding. The average number of insemination was higher (p < .05) from THI <= 70 (2.01) compared to THI >= 80 (3.41). Cows calving during an absence of heat stress (THI <= 70) have the shortest average calving intervals (CI: 420 +/- 15.1 days). Contrastly, calving in the condition of heat stress (THI >= 80) has the longest CI (487 +/- 12.8 days). For each point increase in the THI value above 67, there is a decrease in the first conception rate by 1.39%. In this particular arid environment, high-yielding Holstein cows' breeding success is strongly affected by heat stress that takes place just before or after breeding.
英文关键词	conception rate fertility services per pregnancy Temperature-Humidity Index
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000554391100001
WOS关键词	ARTIFICIAL-INSEMINATION ; PREGNANCY RATES ; NATURAL SERVICE ; COWS ; PERIODS ; TEMPERATURE ; FERTILITY ; IMPACT ; HERDS
WOS类目	Agriculture, Dairy & Animal Science ; Reproductive Biology ; Veterinary Sciences
WOS研究方向	Agriculture ; Reproductive Biology ; Veterinary Sciences
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/325321
作者单位	[Djelailia, Hanane; Najar, Taha] Univ Carthage, Inst Natl Agron Tunisie, Lab Rech Mat Mol & Applicat, Tunis, Tunisia; [Bouraoui, Rachid; Jemmali, Bayrem] Univ Carthage, Higher Sch Agr Mateur, LR13AGR02 Lab ADIPARA, Rd Tabarka, Mateur 7030, Tunisia
推荐引用方式 GB/T 7714	Djelailia, Hanane,Bouraoui, Rachid,Jemmali, Bayrem,et al. Effects of heat stress on reproductive efficiency in Holstein dairy cattle in the North African arid region[J],2020,55(9):1250-1257.
APA	Djelailia, Hanane,Bouraoui, Rachid,Jemmali, Bayrem,&Najar, Taha.(2020).Effects of heat stress on reproductive efficiency in Holstein dairy cattle in the North African arid region.REPRODUCTION IN DOMESTIC ANIMALS,55(9),1250-1257.
MLA	Djelailia, Hanane,et al."Effects of heat stress on reproductive efficiency in Holstein dairy cattle in the North African arid region".REPRODUCTION IN DOMESTIC ANIMALS 55.9(2020):1250-1257.