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In the present study, the effect of heat stress, which is commonly observed in the animals of Upper Egypt area in summer, as well as the effect of antioxidant treatment as a thermo‐protective was examined. In this study, the animals (n = 120) were divided into winter group (n = 40, bred during winter) and summer group (n = 80, bred during summer) as well as, animals in the summer group were divided into first subgroup animals (n = 40) and injected with Viteselen intramuscularly (15 ml) twice weekly for 10 weeks and second subgroup animals (n = 40) were not treated (as control). Serum levels of progesterone (P4), oestradiol (E2), cortisol, superoxide dismutase (SOD), lipid peroxidase (LPO) and nitric oxide (NO) were measured. The pregnancy rate of all animals was detected rectally. The levels of oestradiol and the activity of the antioxidant SOD were decreased in serum of animals in behavioural oestrus during summer as compared with those in winter. During the same time period the levels of oxidants such as LPO and NO were increased in the serum of animals again in the phase of oestrus. In another group of animals treated by intramuscular injection with 15 ml viteselen (antioxidant) twice weekly for 6 weeks during hot months, the activities of serum SOD showed an increase and the levels of oxidants and cortisol decreased. Moreover, the levels of oestradiol were increased during the oestrous behaviour. The pregnancy rate was decreased in animals under heat stress and the pregnancy rate was enhanced dramatically when these animals received antioxidants during the heat stress. This means that the heat‐stress in Upper Egypt may affect the fertility of animals and pregnancy rate and this effect may be through an increased production of free radicals and decreased production of antioxidants as well as increased levels of cortisol. Treatment of animals or supplementation with antioxidants before the beginning of months of heat‐stress and also during the stress period may correct the infertility due to heat‐stress through the decrease in cortisol secretion and a decrease in the oxidative stress. These results resulted in an increase in pregnancy rate in treated animals. 相似文献
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Hicham Seri Mohsen Chammem Luis MM Ferreira Marwa Kechnebou Touhami Khorchani Severiano R Silva 《African Journal of Range and Forage Science》2018,35(2):89-100
Behaviour and diet composition are critical elements in conservation biology within the scope of reintroduction programs. Here we focused on addax (Addax nasomaculatus), a Critically Endangered antelope species, in the Jbil National Park, Tunisia. In this study, we advanced the hypothesis that season, day period, sex and social structure have an effect on the activity budgets and diet composition of addax. Three groups were selected (large group, adult pair and solitary male). Resting, moving, grazing, vigilance and other behaviours were recorded during two seasons (dry and wet) and in the morning and the afternoon. In addition, faecal samples were collected. The results indicate that season and day period were the main factors affecting the activity budgets. The resting behaviour increased from the wet to the dry season, and from morning to afternoon. The grazing and moving behaviours increased during the wet season and decreased from morning to afternoon. Addax select a mixed diet composed of perennial and herbaceous plant species notably during the wet season. In addition, we observed that addax modify their behaviour according to the season and forage availability. This represents an adaptive strategy to survive in a desert climate with a stochastic low-resource environment and depending on ambient climatic conditions. 相似文献
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Histological and immunohistochemical investigations of ovarian interstitial glands during non‐breeding season in camels (Camelus dromedarius) 下载免费PDF全文
The aim of this was to investigate the histology and immunohistochemistry of interstitial glands during non‐breeding season in camel ovaries. A total of 21 mature, non‐pregnant and apparently healthy camels aged between 8 and 12 years were slaughtered. The ovaries were removed within 15 min, cleaned from adipose tissue, weighted and examined grossly. The histological preparation was made, and then, the blocks were cut at 3–5 microns thickness and stained by H&E for histological examinations. Moreover, some sections were stained with Sudan Black for lipid detection. Immunohistochemical analysis of paraffin‐embedded ovarian tissues was performed to detect the localization of S‐100, vimentin, progesterone receptors (PR) and oestrogen receptors (ER). Immunoreactive signals were detected using UltraVision Detection System. The results revealed that the interstitial glands were located in the cortical region and they were arranged in various arrangements either single, in couple or in groups rich in lipid droplet. All interstitial gland arrangements were enclosed by connective tissue capsules containing fibroblasts and collagenous fibres separated them from the surrounding ovarian structures. Both interstitial glands and their surrounding CT were penetrated by several blood vessels. There was a strong immunoreactive signal for S‐100 in the nuclei of interstitial cells, and no signals were detected either in cells of the interstitial glands or their connective tissue with PR. We could conclude that the interstitial gland is distinct in ovary of camel and further studies are needed to elucidate its rule in steroid synthesis. 相似文献
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DJ Skarzynski KK Piotrowska MM Bah A Korzekwa I Woclawek-Potocka K Sawai K Okuda 《Reproduction in domestic animals》2009,44(3):371-379
The aim of study was to correlate tumour necrosis factor-α (TNF) infused doses used with the TNF concentrations achieved and with the secretory function of both the ovary and the uterus in cows. We evaluated the concentrations of progesterone (P4), prostaglandin (PG)F2α , PGE2 nitric oxide (NO) and TNF in the jugular vein and vena cava caudalis as parameters of exogenous TNF action on the female reproductive tract. Aortae abdominalis of cows (n = 18) were infused with saline or two doses of TNF (luteolytic – 1 μg or luteotrophic – 10 μg). In the peripheral blood, 1 μg TNF concentrations achieved within the range of 30–45 pg/ml, and 10 μg TNF provoked a sharp increase in achieved concentrations at a range of 250–450 pg/mL). The TNF concentrations achieved in vena cava caudalis were five to six times higher than that in peripheral blood (p < 0.001). One microgram TNF increased PGF2α and NO (p < 0.001) and decreased P4 (p < 0.05). The higher TNF dose stimulated P4 and PGE2 (p < 0.01). TNF infusion at luteolytic dose achieved its concentrations at the physiological range previously observed in cows. Luteotrophic TNF dose achieved the concentrations in vena cava caudalis that are much higher than physiological level and were previously noted in pathological circumstances (i.e. mastitis , metritis ). 相似文献
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Darrel L. Venable Albert P. Gaudé III Paul L. Klerks 《Journal of the World Aquaculture Society》2000,31(2):158-166
This study evaluated the use of black carp Mylopharyngodon piceus and salinity manipulation for controlling the infection of channel catfish Ictalurus puncratus by a digenetic trematode (tentatively identified as Bolbophorus confusus ). Control methods focussed mainly on the eradication of the intermediate snail host, the marsh rams-horn Phanorbella trivolvis (previously referred to as Helisoma trivolvis ), and were evaluated in laboratory tests and field experiments at a commercial catfish culture facility in southern Louisiana that was seriously impacted by the trematode. Introduction of fingerling black carp into catfish ponds at a density of 62 carpha resulted in an almost total elimination of P. trivolvis . The farm is now successfully using a facility-wide stocking rate of 40 carp/ha. Laboratory experiments were conducted to investigate the effect of salinity manipulation using NaCl on free-swimming trematode cercariae, the snail P. trivolvis , and catfish fingerlings infected with the cercariae. A salinity of 2.5 ppt had a detrimental effect on snail survival, growth, and reproduction. Salinity did not have a negative effect on the other two aspects of the trematode life cycle tested (in fact, survival of both cercariae and infected catfish fingerlings showed a positive dependence on NaCl over the 0–2.5 ppt range). A field-experiment was then conducted in catfish ponds maintained at three salinities (2.5, 1.25, and 0.25 ppt) with rock salt, NaCl. Snail densities in ponds at 2.5 ppt salinity were consistently lower than in the other treatments and no trematode infection was noted among snails or catfish in the 2.5 ppt salinity ponds. Both the use of 2.5 ppt NaCl and black carp appear valuable management tools for controlling the digenetic trematode in caffish ponds. 相似文献
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Pregnancy Rates to Fixed Embryo Transfer of Vitrified IVP Bos indicus,Bos taurus or Bos indicus × Bos taurus Embryos 下载免费PDF全文
LSR Marinho BV Sanches CO Rosa JH Tannura AG Rigo AC Basso JHF Pontes MM Seneda 《Reproduction in domestic animals》2015,50(5):807-811
The pregnancy rates obtained after the transfer of cryopreserved in vitro‐produced (IVP) embryos are usually low and/or inconsistent. The objective of this study was to evaluate the pregnancy rates of Holstein, Gyr and Holstein × Gyr cattle after the transfer of vitrified IVP embryos produced with X‐sorted sperm. Seventy‐two Gyr and 703 Holstein females were subjected to ovum pickup (OPU) sessions, followed by in vitro embryo production using semen from sires of the same breeds. Embryos (1636 Holstein, 241 Gyr and 1515 Holstein × Gyr) were exposed to forskolin for 48 h prior to vitrification. The pregnancy rate achieved with Gyr dam and sire was 46.1%, which was similar (p = 0.11) to that of Holstein dam and Gyr sire (40.3%). Crossing Gyr dams with Holstein sires resulted in a pregnancy rate of 38.9% and did not differ (p = 0.58) from the pregnancy rate obtained with the cross between Holstein dams and Gyr sires. The rate obtained with Holstein dam and sire was 32.5%. The average pregnancy rate was 36.6%, and no difference was found in the proportion of female foetuses (88.8%, in average) among breeds (p > 0.05). In conclusion, transfer of cryopreserved X‐sorted embryos represents an interesting choice for dairy cattle. Despite the small differences between pregnancy rates, we highlight the efficiency of this strategy for all of the racial groups studied. 相似文献
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