scholarly journals Tolerance Capability of Desert Sheep and Goats to Exercise Heat Stress under Hot Dry Conditions, and its Correlation with their Production Performance

2021 ◽  
pp. 106550
Author(s):  
A.M. Aboul-Naga ◽  
M.H. Elshafie ◽  
H. Khalifa ◽  
Mona Osman ◽  
T.M. Abdel Khalek ◽  
...  
2021 ◽  
Vol 58 (3) ◽  
pp. 123-129
Author(s):  
Adel Aboulnaga ◽  
Mohmed Hayder ◽  
Mohmed Abdelkhalek ◽  
Mohmed Shafie ◽  
Taha AbdelSabour ◽  
...  

Animals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 1021
Author(s):  
Veerasamy Sejian ◽  
Mullakkalparambil V. Silpa ◽  
Mini R. Reshma Nair ◽  
Chinnasamy Devaraj ◽  
Govindan Krishnan ◽  
...  

This review attempted to collate and synthesize information on goat welfare and production constraints during heat stress exposure. Among the farm animals, goats arguably are considered the best-suited animals to survive in tropical climates. Heat stress was found to negatively influence growth, milk and meat production and compromised the immune response, thereby significantly reducing goats’ welfare under extensive conditions and transportation. Although considered extremely adapted to tropical climates, their production can be compromised to cope with heat stress. Therefore, information on goat adaptation and production performance during heat exposure could help assess their welfare. Such information would be valuable as the farming communities are often struggling in their efforts to assess animal welfare, especially in tropical regions. Broadly three aspects must be considered to ensure appropriate welfare in goats, and these include (i) housing and environment; (ii) breeding and genetics and (iii) handling and transport. Apart from these, there are a few other negative welfare factors in goat rearing, which differ across the production system being followed. Such negative practices are predominant in extensive systems and include nutritional stress, limited supply of good quality water, climatic extremes, parasitic infestation and lameness, culminating in low production, reproduction and high mortality rates. Broadly two types of methodologies are available to assess welfare in goats in these systems: (i) animal-based measures include behavioral measurements, health and production records and disease symptoms; (ii) resources based and management-based measures include stocking density, manpower, housing conditions and health plans. Goat welfare could be assessed based on several indicators covering behavioral, physical, physiological and productive responses. The important indicators of goat welfare include agonistic behavior, vocalization, skin temperature, body condition score (BCS), hair coat conditions, rectal temperature, respiration rate, heart rate, sweating, reduced growth, reduced milk production and reduced reproductive efficiency. There are also different approaches available by which the welfare of goats could be assessed, such as naturalistic, functional and subjective approaches. Thus, assessing welfare in goats at every production stage is a prerequisite for ensuring appropriate production in this all-important species to guarantee optimum returns to the marginal and subsistence farmers.


2021 ◽  
pp. 106499
Author(s):  
A.M Aboul Naga ◽  
T.M. Abdel Khalek ◽  
Mona Osman ◽  
A.R. Elbeltagy ◽  
E.S. Abdel-Aal ◽  
...  

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1286
Author(s):  
Guangju Wang ◽  
Xiumei Li ◽  
Ying Zhou ◽  
Jinghai Feng ◽  
Minhong Zhang

This paper investigated the effects of heat stress on gut-microbial metabolites, gastrointestinal peptides, glycolipid metabolism, and performance of broilers. Thus, 132 male Arbor Acres broilers, 28-days-old, were randomly distributed to undergo two treatments: thermoneutral control (TC, 21 °C) and high temperature (HT, 31 °C). The results showed that the average daily gain (ADG), average daily feed intake (ADFI), and gastric inhibitory polypeptide (GIP) concentration in the jejunum significantly decreased the core temperature, feed conversion ratio (FCR), and ghrelin of the hypothalamus, and cholecystokinin (CCK) in jejunum, and serum significantly increased in the HT group (p < 0.05). Exploration of the structure of cecal microbes was accomplished by sequencing 16S rRNA genes. The sequencing results showed that the proportion of Christensenellaceae and Lachnospiraceae decreased significantly whereas the proportion of Peptococcaceae increased at the family level (p < 0.05). Ruminococcus and Clostridium abundances significantly increased at the genus level. Furthermore, the content of acetate in the HT group significantly increased. Biochemical parameters showed that the blood glucose concentration of the HT group significantly decreased, and the TG (serum triglycerides), TC (total cholesterol), insulin concentration, and the insulin resistance index significantly increased. Nonesterified fatty acid (NEFA) in the HT group decreased significantly. In conclusion, the results of this paper suggest that the poor production performance of broilers under heat stress may be related to short-chain fatty acids (SCFAs) fermented by intestinal microbiota involved in regulating metabolic disorders.


2019 ◽  
Author(s):  
Wenwu Zhang ◽  
Jiguo Xu ◽  
Hongmei Li ◽  
Lianghui Zhou ◽  
Qinghua Nie ◽  
...  

Abstract Background As a major stressor, high temperatures negatively affect the poultry industry, through impairments to chicken immunity and production performance. The purpose of this study is to clarify how chicken immune systems responded to heat stress with and without immunization. In the present study, spleen and bursa of Fabricius of experimental chickens were subjected to RNA-seq. Key genes influencing immune response in heat-stressed chickens were identified and their functions validated. Results Immunized and heat-stressed chickens experienced a significant reduction in immune function. The expression of immune-related genes and heat stress-related genes in the spleen increased after immunization and decreased after heat stress, but in the bursa of Fabricius, few of these genes were differentially expressed after immunization and heat stress, indicating insensitivity to high temperature and the lack of vaccine processing. In the non-heat-stressed groups, spleen expression of DUSP1 and HSPA5 decreased significantly, suggesting their relationship to immunity. Upon DUSP1 or HSPA5 overexpression, the mRNA expression of MHC-I, MHC-II, CD80, CD86, CD1C, IL1B, IL6, and TLR4 was earlier than that under LPS stimulation only, indicating that DUSP1 or HSPA5 overexpression enhances HD11 recognition LPS. Inhibiting DUSP1 or HSPA5 expression, the mRNA expression levels of MHC-I, MHC-II, CD80, CD86, IL6 and TLR4 did not change significantly from LPS-stimulation-only levels but CD1C significantly decreased, suggesting that HD11 recognition of LPS is affected by DUSP1 or HSPA5 expression levels. Conclusions The inhibition of immune response due to lowly expressed DUSP1 and HSPA5 may be the cause of decreased immunity in chickens.


1994 ◽  
Vol 42 (3) ◽  
pp. 307
Author(s):  
PK Groom ◽  
BB Lamont ◽  
L Kupsky

We studied the morphology, anatomy, phyllotaxy and daily seasonal ecophysiology of the two leaf types (broad and terete) of Hakea trifurcata (Smith) R.Br., a widespread shrub in south-western Australia. Both leaf types may be present on the same branchlet, with one or two broad leaves forming first during the annual growth period (late winter) followed by many terete leaves in spring. Terete leaves were more xeromorphic than broad leaves, including greater thickness, denser tissues and fewer veins. Broad leaves fixed more carbon and transpired more water per unit mass than terete leaves, in a well ventilated leaf chamber, and had lower (more negative) xylem pressure potentials. Broad leaf temperatures only exceeded those of terete leaves under hot, dry conditions, with no relationship between transpiration rates and leaf temperature. Terete leaves possessed many structural and physiological characteristics commonly associated with drought-tolerant leaves, whereas broad leaves were characteristic of leaves which keep their stomates open during periods of water and heat stress. Both leaf types appear to increase the fitness of this species in a mediterranean climate, with broad leaves having the potential to supply extra photosynthates and nutrients to the new season's growth.


2017 ◽  
Vol 17 (1) ◽  
pp. 59-88 ◽  
Author(s):  
Amani Al-Dawood

Abstract Small ruminants (sheep and goats) play a predominant role in the economy of million people, and have provided meat, milk, skin, wool and fiber for centuries. Animals undergo various kinds of stressors, i.e. physical, nutritional, chemical, psychological and heat stress (HS). Among all, HS is the most concerning at present in the ever-changing climatic scenario. Climate change is the most serious long-term challenge faced by small ruminants’ owners worldwide. HS results in decreased growth, reproduction, production, milk quantity and quality, as well as natural immunity, making animals more vulnerable to diseases, and even death. Thus, HS results in great economic losses, emphasizing the necessity to objectively assess animal welfare. The increasing demand for animal products paralleled by the frequent hot climate is a serious threat for the agriculture sector. The ability of sheep and goats to cope with HS without harming their welfare and productive performance has been often overrated. To date, little attention has been paid to comprehensive detailed data on the adverse effect of HS on sheep and goats. Therefore, this review discusses in detail the sheep and goats’ behavioral, physiological, molecular/cellular, hematological, biochemical and immunological responses under HS conditions. In addition, this review also presents the adverse effects of HS on reproduction and fertility, milk quantity and quality, feed intake, and water consumption of sheep and goats. Finally, this review suggests various methods for HS alleviation. In conclusion, HS impairs productivity and well-being in sheep and goats. The improved understanding of the impact of HS on small ruminants will help in developing management techniques to alleviate HS and highlighting the need for future researches on HS in sheep and goats.


2021 ◽  
Vol 8 ◽  
Author(s):  
Kaho Kitajima ◽  
Kazato Oishi ◽  
Masafumi Miwa ◽  
Hiroki Anzai ◽  
Akira Setoguchi ◽  
...  

Heart rate variability (HRV) is the heart beat-to-beat variation under control of the cardiovascular function of animals. Under stressed conditions, cardiac activity is generally regulated with an upregulated sympathetic tone and withdrawal of vagal tone; thus, HRV monitoring can be a non-invasive technique to assess stress level in animals especially related to animal welfare. Among several stress-induced factors, heat stress is one of the most serious causes of physiological damage to animals. The aim of this study was to assess the effects of heat stress on HRV in small ruminants under free-moving conditions. In three experimental periods (June, August, and October), inter-beat intervals in sheep and goats (three for each) in two consecutive days were measured. HRV parameters were calculated from the inter-beat interval data by three types of analyses: time domain, frequency domain, and non-linear analyses. The temperature–humidity index (THI) was used as an indicator of heat stress, and vectorial dynamic body acceleration (VeDBA) was calculated to quantify the physical activity of the animals tested. First, we investigated correlations of THI and VeDBA with HRV parameters; subsequently, THI was divided into five categories according to the values obtained (≤ 65, 65–70, 70–75, 75–80, and &gt;80), and the effects of the THI categories on HRV parameters were investigated with and without correcting for the effects of physical activity based on the VeDBA. The results indicated that HRV significantly decreased with increasing THI and VeDBA. For non-linear HRV parameters that were corrected for the effects of physical activity, it was suggested that there would be a threshold of THI around 80 that strongly affected HRV; high heat stress can affect the autonomic balance of animals non-linearly by inducing the sympathetic nervous system. In conclusion, to assess psychophysiological conditions of unrestrained animals by HRV analysis, the confounding effect of physical activity on HRV should be minimized for a more precise interpretation of the results.


2020 ◽  
Vol 23 (16) ◽  
Author(s):  
AL-Enzy AFM ◽  
Zaeid J. M. Saed ◽  
Ahmed S. Naser ◽  
Th. T. Mohammed ◽  
S. M. Abdulateef ◽  
...  

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