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131.
Oryan Ahmad Ahmadi Nasrollah Mousavi Seyed Mostafa Modarres 《Tropical animal health and production》2010,42(7):1513-1518
This study was conducted to determine the prevalence, distribution pattern, and the Sarcocystis species involved in slaughtered water buffaloes (Bubalus bubalis) in the Khuzestan, Iran by macroscopic and histological examination. The esophagus, heart, diaphragm, tongue, masseter, and
thigh muscles were investigated. Esophagus and thigh muscles of only 3 of the 100 examined water buffaloes (3%) were infected
with macroscopic Sarcocystis, whereas at microscopic level Sarcocystis were found in 83 of the 100 examined animals (83%). The highest prevalence rate of microscopic cysts was found in masseter
muscle (57.1%) and then followed by tongue, diaphragm, esophagus, heart, and finally, thigh muscles (30.0%). There was no
significant difference between males (83.6%) and females (82.0%) or between two investigated age groups (≤2 years old, 78%
versus >2 years old, 88%). Based on the size of the sarcocysts, thickness of the walls and location of the cysts, Sarcocystis buffalonis as a macroscopic form and Sarcocystis levinei and Sarcocystis dubeyi as the microscopic forms were diagnosed in the examined muscles of the buffaloes of this area. Sarcocystis fusiformis was not seen in the examined organs of these buffaloes. The high prevalence rate of microscopic Sarcocystis in this region indicates that dogs have a more significant role than cats in transmission of these protozoa. 相似文献
132.
Reproductive performance of Holstein dairy cows in Iran 总被引:2,自引:2,他引:0
Maryam Ansari-Lari Mojtaba Kafi Mohammad Sokhtanlo Hasan Nategh Ahmadi 《Tropical animal health and production》2010,42(6):1277-1283
The objectives of the present study were to describe the current reproductive parameters of Holstein dairy cows in Iran and
to determine factors which have a significant effect on reproductive performance with emphasis on high-producing dairy cows.
Five large Holstein dairy herds from the major milk production areas of Iran were selected for this study. Reproduction data
including parity of dam, calving date, days to first service, days open, number of services, dry period, and occurrence of
diseases for cows that calved from 2004 to 2007 were collected from the herds' databases. To determine the effects of year
and season of calving, disease status, level of milk production, and parity of dam on reproductive parameters, the proc-mixed
procedure in SAS software was used. Overall, data about 8,204 lactation were collected for the study. Results showed that
mean (±SD) days open, calving interval, and days to first service for study herds were 134 (±89), 403 (±86), and 67 (±38)
days, respectively. Conception rates at the first service and the overall service-conception rate were 41.6% and 41%, respectively.
The level of milk production and diseases had significant negative effects on days open and service per conception (P < 0.05); statistical analysis showed that for every 100-kg increase in milk yield, days open will increase by about 0.3 days.
However, no significant effect of level of productivity was observed on days to first service. The results of this study indicate
that high milk production is a risk factor for decreasing fertility in Iran, like many other parts of the world. 相似文献
133.
Mojtaba Moradi Isaac Karimi Shirin Ahmadi Layth J. Mohammed 《Reproduction in domestic animals》2020,55(9):1027-1043
The inclusion of antioxidants (AOXs) has been proposed in various protocols to conserve the normal physiology of spermatozoa during (cryo) preservation. The main aim of this review was to understand the necessity of AOXs inclusion in semen extenders of caprine and ovine semen samples and to decipher physico-chemical space of AOXs used in semen extenders till now. A total 27 full-text relevant articles were finally discussed here. This systematic review showed that the inclusion of AOXs may improve the success of semen cryopreservation although at least three studies could not support this finding. AOXs have been not added after assaying total antioxidant capacity of the sample of interest, and this is principal measurement bias of all papers. Furthermore, no rational dose–response curve and precise posology have been considered in comparable studies. Furthermore, new methodologies are requested to detect the oxidative status of semen specimens before AXOs fortification and new methodologies like imaging are also needed to detect various injuries of sperms during semen (cryo)preservation. Defining computational chemical and physical spaces of AOXs which used in semen (cryo)preservation would be an interdisciplinary effort to hasten deciphering epoch-making compounds. In conclusion, more in-depth analytical, toxicological and pharmacological methodologies should be pursued in supplementation or addition of AOXs during caprine and ovine semen (cryo)preservation after determining the oxidative status of semen samples. 相似文献
134.
135.
Ali Kadivar Mohammad Rahim Ahmadi Mahmood Vatankhah 《Tropical animal health and production》2014,46(1):121-126
This study was performed to investigate the effect of periparturient body condition score on the occurrence of clinical endometritis and postpartum resumption of ovarian activity in dairy cows. Eighty-seven lactating Holstein cows, fed with a total mixed ration diet, were included into the study. Body condition scoring (using a 5-point scale with quarter-point divisions) was performed by the same investigator using the visual technique every 2 weeks, from 2 weeks before until 6 weeks after calving. Palpation of the reproductive tract and ultrasonographic assessment of ovaries for detection of corpus luteum using a rectal linear probe was also performed at 2, 4, and 6 weeks after calving. Cows with clinical endometritis had significantly lower body condition score (BCS) than normal cows at all weeks pre- and postcalving, and cows that did not ovulate until 45 days after calving had a significantly lower BCS pre- and postpartum. Cows that did not ovulate until 45 days after calving also lost more BCS from 2 weeks before to 4 weeks after calving. Besides, first ovulation after calving take occurred later in cows with clinical endometritis compared to normal cows (P?<?0.05). In conclusion, low BCS is a risk factor for postpartum endometritis and delayed cyclicity in dairy cows. BCS loss from dry-off to early lactation and occurrence of clinical endometritis can significantly affect postpartum ovarian activity. 相似文献
136.
Abolfazl Shirazi Ebrahim Ahmadi Majid Jadidi Naser Shams-Esfandabadi Banafsheh Heidari 《The Canadian veterinary journal. La revue veterinaire canadienne》2009,50(5):501-505
This is the first report of an acephalous lamb from the transfer of an in vitro-produced sheep embryo. Twelve in vitro-fertilized embryos were transferred to 4 recipient ewes (3 embryos/ewe). Two ewes remained pregnant: one delivered a normal female lamb, the other a male acephalous lamb. Possible contributing factors are discussed. 相似文献
137.
Reza Asadzadeh Aliashraf Mozafari Elham Shafiei Mohammadreza Kaffashian Iraj Ahmadi Mohammadzaman Darvish Saiyad Bastaminejad 《Iranian Biomedical Journal》2022,26(5):289
Background:Anemia often worsens the severity of respiratory illnesses, and few studies have so far elucidated the impact of anemia on COVID-19 infection. This study aimed to evaluate the effect of anemia at admission on the overall survival of COVID-19 patients using AFT models. Methods:This registry-based, single-center retrospective cohort study was conducted in a university hospital in Ilam, the southwest of Iran, between March 2020 and September 2021. AFT models were applied to set the data of 2,441 COVID-19 patients. Performance of AFT models was assessed using AIC and Cox-Snell residual. On-admission anemia was defined as Hb concentration <120 g/l in men, <110 g/l in women, and <100 g/l in pregnant women. Results:The median in-hospital survival times for anemic and non-anemic patients were 27 and 31 days, respectively. Based on the AIC and Cox-Snell residual graph, the Weibull model had the lowest AIC and it was the best fitted model to the data set among AFT models. In the adjusted model, the results of the Weibull model suggested that the anemia (adjusted TR: 1.04; 95% CI: 1.00-1.08; p = 0.03) was the accelerated factor for progression to death in COVID-19 patients. Each unit of increase in hemoglobin in COVID-19 patients enhanced the survival rate by 4%. Conclusion: Anemia is an independent risk factor associated with the risk of mortality from COVID-19 infection. Therefore, healthcare professionals should be more sensitive to the Hb level of COVID-19 patients upon admission.Key Words: Anemia, COVID-19, Risk factors, Mortality, Survival 相似文献