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141.
Double-outlet right ventricle in a 10-month-old Friesian filly   总被引:1,自引:1,他引:0  
A 10-month-old Friesian filly had a presentation that was consistent with chronic left- and right-sided congestive heart failure. Clinical pathology findings included abnormal haematological and biochemical variables, abnormal blood gas values and increased serum concentration of cardiac troponin I. Echocardiography revealed cardiac chamber dilation and dextropositioning of the aorta. Radiography revealed a generally enlarged heart and pulmonary interstitial infiltration. These findings were supported at necropsy and the diagnosis of double-outlet right ventricle was confirmed. The pathological changes and physiological responses subsequent to double-outlet right ventricle have not previously been described in detail in horses. Clinical progression closely resembles that seen in humans, in whom antemortem diagnosis relies on echocardiography. In horses, complex cardiac disease presents a diagnostic challenge to the clinician. Appropriate therapy must be based on an accurate diagnosis.  相似文献   
142.
Nitrate–nitrite poisoning killed four adult alpacas and induced the abortion of a full-term fetus after access to oaten hay ( Avena sativa ) containing 3.2% KNO3 equivalent in dry matter. Necropsy findings were cyanosis, dark-coloured blood, and pulmonary congestion and oedema. Aqueous humour from two adults contained 25 mg NO3/L and that from the fetus contained 10 mg NO3/L. Cyanide poisoning possibly killed two adult wether alpacas that ate a garden-cultivated variety of Osteospermum ecklonis (South African daisy, bietou) with a cyanide potential of 6800 mg HCN/kg dry matter.  相似文献   
143.
There has been limited investigation of parturition in the bitch and there is little information published on clinical and obstetrical examination other than opinion and anecdote. While there are substantial data on haemodynamic and vascular changes during normal parturition in humans, little is known about the physiological events in the dog. This study was aimed at maternal haemodynamic changes occurring during normal parturition and to investigate how these were modified in bitches with dystocia (DYST) treated either medically or via assisted delivery and caesarean operation. Three groups of 10 bitches were investigated; those with normal parturition, those with DYST corrected by manipulative assistance or caesarean operation and those with uterine inertia treated by oxytocin administration. Heart rate, systolic and diastolic blood pressure, electrocardiogram and blood glucose concentration were measured pre-partum, intra-partum, immediately after parturition and 1 h later. Heart rate was high at all times throughout the study and the majority of bitches had normal sinus rhythm. Blood pressure was generally within the normal range, and although systolic and diastolic blood pressure was highest during the intra-partum period and sometimes during the immediate post-partum period, there were no significant differences between groups. All bitches had blood glucose concentrations within the normal range throughout the study although pre-partum concentrations were statistically lower than many of the other time periods. The study provides useful physiological data that will facilitate monitoring and clinical management of bitches throughout normal parturition and DYST.  相似文献   
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To investigate the mechanisms inducing sperm death after ejaculation, stallion ejaculates were incubated in BWW media during 6 h at 37°C. At the beginning of the incubation period and after 1, 2, 4 and 6 h sperm motility and kinematics (CASA), mitochondrial membrane potential and membrane permeability and integrity were evaluated (flow cytometry). Also, at the same time intervals, active caspase 3, hydrogen peroxide, superoxide anion (flow cytometry) and Akt phosphorylation (flow cytometry) were evaluated. Major decreases in sperm function occurred after 6 h of incubation, although after 1 h decrease in the percentages of motile and progressive motile sperm occurred. The decrease observed in sperm functionality after 6 h of incubation was accompanied by a significant increase in the production of hydrogen peroxide and the greatest increase in caspase 3 activity. Additionally, the percentage of phosphorylated Akt reached a minimum after 6 h of incubation. These results provide evidences that sperm death during in vitro incubation is largely an apoptotic phenomena, probably stimulated by endogenous production of hydrogen peroxide and the lack of prosurvival factors maintaining Akt in a phosphorylated status. Disclosing molecular mechanisms leading to sperm death may help to develop new strategies for stallion sperm conservation.  相似文献   
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