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ALEKSIEV, Y., 2009. The effect of shearing on the behaviour of some physiological responses in lactating Pleven Blackhead ewes. Bulg. J. Agric. Sci., 15: 446-452 Rectal temperature (RT), pulse rate (PR), and respiratory frequency (RF) were collected for 6 days before shearing and for 15 days thereafter, in the morning and in the afternoon. Morning...
Citations
... The temperature of lambs aged 1-30 days ranges from 39.1 to 39.8℃ under normal conditions. The rectal temperature of a newborn lamb fluctuates until 30 days of age, probably due to two factors: Thermoregulation in Lamb is not very specific, or the mechanism of thermoregulation is still under development (Aleksiev 2009). In this study, the normal physiological response of Lamb suggests that the ewe diet treatment is still able to maintain the thermoregulation of the body in good condition, even though the temperature conditions during the daytime environment may cause increased stress. ...
Nutrition can influence lamb survival and the immune status during the neonatal phase until weaning.  This study aimed to investigate the effect of flushing of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) from Lemuru fish oil in the Ewe's diet on lamb immunity and survival. Twenty-eight neonatal lambs were divided into four treatments according to Ewe's diet. Four treatments: control concentrate (P1), flushing concentrate with 6% palm oil (P2), flushing concentrate with 3% lemuru oil and 3% palm oil (P3), and flushing concentrate with 6% lemuru oil (P4). The Ewe were fed Napier grass and concentrated in a 30:70% ratio based on dry matter. Ewe and their lambs remained together until weaning at about two months of age. The parameter observed in ewes was colostrum Immunoglobulin G (IgG).  The parameters in the Lamb are blood Ig G, neonatal behavior of the Lamb, physiological response, and hematology of the Lamb at birth and weaning. The results showed that feeding P4, P3, and P2 to the Ewe resulted in a shorter latency to stand-in lamb (P0.05). P1 has higher leukocytes (P0.05) during weaning than P2 and P3. P1 has the same leukocyte as P4. Treatment has a non-significant effect (P0.05) on Ig G and physiological response. In conclusion, administering 6% Lemuru oil containing EPA and DHA twice can shorten the latency to stand in newborn lambs.
... Thus, different globulin fractions are not the only parameters to be considered in order to evaluate the severity of an acute-phase response [16,17]. The physiological adaptation of sheep to shearing has been extensively investigated in the field of hematochemical response as well as a thermal homeostasis alteration of the sheared animal's thermoregulation [4,[18][19][20][21][22][23][24][25][26][27][28]. However, the early stress response of sheep to shearing has been poorly investigated. ...
The current study aimed to investigate the influence of acute stress by shearing procedures on hematological parameters, serum cortisol concentration and serum protein electrophoretic pattern in Comisana sheep. A total of 20 not pregnant and not lactating adult ewes, aged 3–4 years old and with a mean bodyweight of 55.50 ± 3.50 kg, were enrolled in the study. From each animal, blood samples were collected before shearing (TPRE) and 5 (TPOST5) and 60 (TPOST60) minutes after the end of the shearing procedure in order to assess the values of hematological parameters, serum cortisol, total proteins and protein fractions, including albumin, α-, β1-, β2- and γ-globulins. According to statistical analysis results, albumin values were lower at TPOST60 than TPOST5 (p < 0.01), whereas α- and β2-globulins and the A/G ratio were higher at TPOST60 with respect to TPRE (p < 0.01) and TPOST5 (p < 0.01). A higher serum concentration of cortisol was found at TPOST5 and TPOST60 than TPRE (p < 0.01), and at TPOST60 than TPOST5 (p < 0.01). The serum cortisol values were negatively correlated with the serum values of albumin, β1-globulins and A/G ratio at TPOST60, and positively correlated with α- and β2-globulins at TPOST5 and TPOST60. The decrease in the albumin concentration and the increase in the α- and β2-globulins observed in ewes after shearing with respect to the baseline values suggests an acute phase response in shorn ewes. Additionally, the correlation found between the serum cortisol concentration and the serum protein fractions confirmed the immunomodulatory effect of this hormone, emphasizing the linkage between the endocrine and immune systems during an acute stress condition.
... Conversely, Dwyer and Morgan [54], and Miller et al. [55] found that neonatal rectal temperature is directly related to birth weight. As previously indicated, the difference in rectal temperature at birth could be related to the degree of maturity and birth order of the newborn; the fetus that grows fastest and thus reaches mature weight sooner is the firstborn [25,56]. It seems likely that a low birth weight leads to the activation of the neonate's homeothermic mechanism, increasing its thermoregulatory capacity [57], perhaps due to the ability of brown adipose tissue to increase metabolism by the regulation of circulating metabolic hormones and metabolites [54,[58][59][60]. ...
... Heart rate should reflect homeostatic and nutritional status, and the development of the heart tissue [67], so it is seen as an indicator of physiological stress that itself is related to metabolic activation in the neonate [68]. The newborn loses a large amount of body heat through the skin in the first hours after parturition, as it adapts to its new environment, leading to a decrease in respiration rate [56,69]; therefore, it is possible to hypothesize that the newborns with lower respiration rate presented a better adaptation to the new environment [70]. Moreover, we found that newborn singletons had a higher heart rate than twins or triplets, whereas triplets had a higher respiratory rate than singletons or twins. ...
The last third of gestation is a period of high energy demand for the dam because she needs to support the growth of fetuses and the newborn. Moreover, towards the end of gestation, maternal feed intake is reduced as the mass of the fetoplacental unit increases. The maternal diet often cannot meet nutritional requirements, compromising thermoregulatory capacity, wellbeing, and viability, and the survival of the newborn. We have shown that energy supplementation of the mother during the last third of gestation does not affect progeny birth weight but enhances mother-young bonding
... Shearing is a routine work in the different sheep rearing systems to harvest wool. In extreme environments, shearing modifies the magnitude and direction of heat exchange and shifts the thermo-neutral zone that impeding the maintenance of homeothermy [4]. ...
... The physiological responses of sheep differ according to the surrounding climatic conditions of the shearing season [26], [27] and [28]. Irrespective of season, shearing is associated with some degree of thermal stress that might affect the welfare and productivity of sheep [4] by altering its thermal balance [21] and shifting adaptive thermogenesis via nervous responses to readjust energy saving mechanisms related to climatic adaptability [2], [8] and [20]. ...
... effect of treatment, day and treatment × day interaction on body weight change that lead to the obvious variations between shorn and unshorn ewes in their body weight responses to shearing and the climatic conditions records at each day point. Fleece provides protection against extreme heat exchange between the naked skin and the ambient air to maintain constant body temperature and lower energy 16 [4], [10] and [20]. Therefore, removing the fleece enhances heat dissipation from the body surface to the surrounding environment and shifts the thermoregulatory set point that leading to higher utilization of body reserves to meet the elevated energy requirements [2], [21] and [8]. ...
... Although fleece is important to maintains homeothermy under hot and cold conditions due to the extremely low thermal conductivity of wool that maintains a high thermal gradient between atmosphere and the skin (Piccione and Caola, 2003), shearing was found to alter the thermoregulation and the homeostasis mechanisms of sheep (Pennisi et al., 2004;Casella et al., 2016) as it stimulates adaptive thermogenesis by stimulating nervous responses to modify the thermoregulation and energy saving mechanisms that related to climatic adaptability (Aleksiev, 2009). Rather than there are evidence that shearing could evoke metabolic responses to maintain thermoregulatory mechanisms (Piccione et al., 2008), motivates feed intake of sheep (Avondo et al., 2000;Revel et al., 2000) and stimulate lamb growth rate and might reflect positively on lamb's performance (Mclean et al., 2015). ...
... However, this traditional practice also means harvesting the fleece which provides protection against the external factors. In some of the studies performed in this field, it was reported that shearing increased the sen sitivity of the animals to thermal stress [8,1015], in others [2,16,17], that the removal of fleece did not have a signifi cant effect on the physiology of the sheep or that sheep were becoming more resistant to thermal stress after shearing. However, fleece properties of sheep have a very important role in the response of sheep to thermal stress [18]. ...
... It has been reported that at high ambient temperatures, shorn ewes dispersed 50% of body heat by means of evaporation better than unshorn ewes [29]. These findings were consistent with the findings obtained from previous studies [14,16,17,30,31] conducted in different sheep breeds. ...
Shearing is one of the practices that is applied periodically to fiber producing animals, which can also alter resistance of animals to high temperatures in especially summer months. This study aimed to investigate effects of shearing on some physiological and hormonal parameters in Akkaraman sheep during summer season.
Methods
39 non-pregnant Akkaraman ewes (aged 1.5 years at the beginning of experiment) were used in this study. The 39 ewes were chosen randomly from the flock belonging to the Erciyes University and they were assigned to two groups as follows: 1) group A (n=20) designed as the control group, they were shorn and group B (n=19) designed as the experimental group, they were unshorn. Prior to the shearing (-1 day) and on days 1, 7, 15, 30, 45, 60, 75 and 90 following the shearing, blood samples were taken from the vena jugularis of each sheep. Cortisol, β-Endorphin, growth hormone (GH), thyroxine (T4), triiodothyronine (T3) and heat shock protein 70 (HSP-70) concentrations were determined using the enzyme immunoassay (EIA) method. Body weight (BW), rectal temperature (RT), pulse rate (PR) and respiratory rate (RR) of each sheep were recorded at the same time. The data obtained were analyzed using two-way repeated measures analysis of variance (ANOVA).
Results
Statistical analysis showed a significant effect of shearing x period interaction (p<0.01) and a significant effect of period (p<0.01) on BW, HSP-70, cortisol, T4 and RT, PR, GH, β-Endorphin, T3, respectively. Also these analysis showed no significant effect of shearing x period interaction or period on RR.
Conclusion
The results showed that the thermoregulation abilities of sheep were affected by shearing treatment and the shorn ewes were more effected by heat stress. In conclusion, based on the data of this study, shearing can be considered as a necessary management practice that requires protection for sheep from the effect of heat stress.
... Therefore, immediately after shearing there are important increases in cortisol concentrations [12,26,39], and in body temperature [35,39], indicating that the procedure is strongly stressful. Moreover, animals cannot cope quickly with stress of shearing, as they are expose during several days to a thermic stressor, especially after winter shearing [2,3]. The first days after winter shearing body temperature decreases [24], and thus, ewes change their behavioural strategy, reducing the heat loss by decreasing their lying time, and thus, the contact with the soil [4]. ...
High progesterone concentrations reduce the stress responses in several mammals. Therefore, it may be expected that pregnant ewes have lower responses to stressors than anoestrous ewes. Our aims were to compare the stress response and the behavioural changes of pregnant and non-pregnant ewes sheared during winter. Two trials were with 20 were pregnant (group PR) and 17 non-pregnant ewes (group NP). In the first trial blood samples were collected immediately before and during the first 180 min after shearing, and cortisol, total protein, and albumin concentrations were measured, and globulin concentrations were calculated. In the second trial, the frequency in which each ewe was observed standing, lying down, walking and grazing were recorded from Day −3 to Day −1 (Day 0 = shearing), from Day 1 to Day 5, on Days 13 and 20–21 during 8 h/day. Scan observations were done every 10 min from 8:00 h to 12:00 h and from 14:00 h to 18:00 h (total = 50 recordings.day). Non-pregnant ewes had greater cortisol concentrations than PR ewes (P = .007). Non-pregnant ewes also had greater total protein concentrations than PR ewes (P = .029). Albumin concentration tended to be greater in NP than PR ewes (P = .064). Globulin concentration 30 min after shearing was greater in PR than in NP ewes (P = .047). Pregnant ewes were observed more frequently standing than NP ewes (P = .013). Non-pregnant ewes were observed more frequently lying down and walking than PR ewes (P = .039 and P = .009, respectively). Before shearing, on Day 2 and Day 4, NP ewes walked more frequently than P ewes (P = .007, P < .0001, P = .007 respectively). Pregnant ewes were observed grazing more frequently than NP ewes (P = .009). Pregnant ewes grazed more than NP ewes on Days 1 and 5 (P = .005 and P < .0001 respectively). Overall, we concluded that shearing was a strong stressor that provoked sustained changes in the behavioural pattern, physiological status and gregariousness intensity despite being or not pregnant. Some responses, as cortisol concentration, changes in the time walking and grazing and the decrease of the cohesiveness after shearing seem to be less pronounced in pregnant than in non-pregnant ewes.
... During this practice, the exposition to dogs or unknown humans, movement to unfamiliar pens, sounds and movements related to shearing of other animals, restrainment during shearing trigger acute stress responses, but this response is maintained over time as a consequence of fleece removal, and the need of animals to adapt to the lack of wool during several days, so shearing is also a chronic stressor (Hargreaves and Huston, 1990b;1990c;Carcangiu et al., 2008). The loss of the wool, especially when animals are shorn during winter, also provokes a thermic stress that remains during several days (Aleksiev, 2008(Aleksiev, , 2009. Shearing triggers important increases in cortisol concentrations (Jephcott et al., 1987;Sanger et al., 2011), glycaemia (Carcangiu et al., 2008), and cardiac and pulse rates (Wodzicka-Tomaszewska, 1963;Mousa-Balabel and Salama, 2010). ...
Our aim was to characterize the behavioural and physiological changes provoked by winter shearing of late pregnant ewes. Twelve ewes were shorn at 120 days of gestation, and the remaining 12 ewes remained unshorn as controls. The frequency in which animals were standing, lying down, and grazing, and the distance to the closest member of the group were recorded from Day -3 to Day -1 (shearing = Day 0), from Day 1 to Day 5, and on Days 13 and 20-21. The blood total protein, albumin and globulin concentrations were also determined in blood samples collected immediately before shearing, and on Days 10, 15 and 22. Shearing pregnant ewes triggered behavioural changes, such as decreased time allocation to resting and greater allocation to standing and grazing than controls possibly reflecting an increased consumption. The time allocated to grazing increased after shearing and remained higher than controls until the end of the study. During the first two days after shearing ewes were more dispersed probably due to difficulties in recognizing flock-mates. Total protein concentration was slightly greater in shorn ewes.
... Shearing induces adaptive thermogenesis in shorn sheep under either extreme or climatically mild atmosphere conditions (Al -Ramamneh et al., 2011). Shearing modificates nervous control mechanisms and readjusts the thermoregulation and energy saving mechanisms that play a major role in post shearing adaptation (Aleksiev, 2009). Under intensive and extensive production systems, shearing is considered as one of the most effective stressors that face sheep (Dikmen et al., 2011;Sanger et al., 2011;Hristov et al., 2012). ...
... Shearing is considered to be stressful to sheep, capable of causing some behavioral changes, including comfort behaviors that change immediately after shearing [4,9] and results in thermal stress [17]. Stressful conditions lead to excessive production of free radicals, which results in oxidative stress. ...
The effects of shearing on behavioral patterns, antioxidants, and inflammatory and stress biomarkers was investigated in Ossimi sheep. Clinical parameters and behavioral patterns were recorded, and serum samples were collected pre-shearing and 1,5,10, and 15 days post-shearing from 60 Ossimi sheep. The results revealed that grooming and standing idle frequencies were significantly (P<0.01) increased post-shearing. There were significant (P<0.01) increases in IL-6, cortisol, and MDA detected from the 1st to the 10th day post-shearing compared to pre-shearing values. IL-2 and TNF-α significantly (P<0.01) increased from the 1st until the 5th day post-shearing compared to pre-shearing values, while significant (P<0.01) decreases in the values of Catalase from the 1st until the 5th day post-shearing compared to pre-shearing values were recorded. Regarding to glutathione reductase, there was a significant (P<0.01) decrease from the 1st until the 10th day post-shearing compared to pre-shearing values. Shearing leads to significant changes in antioxidants, inflammatory, stress biomarkers, and some behaviors in sheep.
