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221.
Prostaglandin F and its analogues (PGF) are widely used in equine reproductive practice. The interval from PGF treatment to ovulation (ITO) varies greatly with a range from 2 to 16 days. Clinical observation suggests that mares mated and ovulated soon after PGF treatment may have poor fertility. Reproductive records of 329 cyclic Thoroughbred mares were analysed retrospectively. The following parameters were analysed: (i) use of cloprostenol; (ii) ITO and (iii) number of ovulations per cycle. According to these parameters, mares were classified into four groups. (i) mares with spontaneous ovulations, n = 57; (ii) mares induced with cloprostenol and ITO = 4–7 days, n = 77; (iii) ITO = 8–10 days, n = 89 and (iv) ITO = ≥11 days, n = 106. Differences in pregnancy (PR) and multiple ovulation (MO) rates among groups were tested using chi‐squared test. PR rates for groups 1–4 were: 73.7%, 46.7%, 64% and 71.7% respectively (p < 0.05). Groups 1 and 2 had lower (p < 0.05) MO rate (24.6% and 20.8%) than groups 3 and 4 (40.4% and 44.3%). It appears that ovulation soon after PGF‐induced luteolysis is detrimental to PR rates. It was found highly significant that in cloprostenol‐treated mares, the MO rate was enhanced without subsequent increase in multiple pregnancies.  相似文献   
222.
Contrast fluoroscopy is a valuable tool to examine avian gastrointestinal motility. However, the lack of a standardized examination protocol and reference ranges prevents the objective interpretation of motility disorders and other gastrointestinal abnormalities. Our goals were to evaluate gastrointestinal motility in 20 Hispaniolan Amazon parrots (Amazona ventralis) by contrast fluoroscopy. Each parrot was crop‐fed an equal part mixture of barium sulfate and hand‐feeding formula and placed in a cardboard box for fluoroscopy. Over a 3‐h period, 1.5 minute segments of lateral and ventrodorsal fluoroscopy were recorded every 30 min. The gastric cycle and patterns of intestinal motility were described. The frequency of crop contractions, esophageal boluses, and gastric cycles were determined in lateral and ventrodorsal views. A range of 3.4–6.6 gastric cycles/min was noted on the lateral view and 3.0–6.6 gastric cycles/min on the ventrodorsal view. Circular measurements of the proventriculus diameter, ventriculus width, and length were obtained using the midshaft femoral diameter as a standard reference unit. The upper limits of the reference ranges were 3.6 and 4.7 femoral units for the proventriculus diameter in the lateral and ventrodorsal view, respectively. Two consecutive measurements were obtained and the measurement technique was found to have high reproducibility. In this study, we established a standardized protocol for contrast fluoroscopic examination of the gastrointestinal tract and a reliable measurement method of the proventriculus and ventriculus using femoral units in the Hispaniolan Amazon parrot.  相似文献   
223.
Until the latter part of the nineteenth century, there were no domestic animals other than pigs, dogs and poultry in the island of New Guinea. From 1889 onwards, occupying authorities, missionaries and settlers from Germany, the UK, Japan and Australia imported ruminants, pigs and horses. Some of these importations were from Asia. This paper describes some outcomes of those importations and the potential hazards for Australia entailed in them.  相似文献   
224.
The clinical, radiographic and post-mortem findings in 6 horses with cryptococcal pneumonia and one horse with an abdominal cryptococcal granuloma are described. In pulmonary cryptococcosis, the lesions were either diffuse and multiple, with bilateral lung involvement, or localised mainly to the dorsocaudal region of one lung. The cases of diffuse multiple cryptococcosis were thought to be associated with haematogenous spread of the fungus after gastrointestinal infection and dissemination from regional lymph nodes. The localised form of the disease was thought to have been associated with inhalation of cryptococci. In all cases of pulmonary cryptococcosis, encapsulated yeast-like organisms were demonstrated in Wright's-stained sediment of tracheal washes. In the horse with the abdominal granuloma, cryptococci were present in a fine needle aspirate sample. Isolates of Cryptococcus neoformans var gattii were recovered from 2 of the 5 horses in which cultures were attempted. In addition to a history of previous illness that may have predisposed to infection, most horses in this report had been in areas in which Eucalyptus camaldulensis, or the closely related E rudis, were growing. In humans, an epidemiological relationship between E camaldulensis and infection with C neoformans var gattii has been suggested. Cases of equine cryptococcosis carry a poor prognosis and treatment was not attempted in any of these cases.  相似文献   
225.
Fourteen horses that could not perform at their expected standards due to chronic back pain of 4 to 48 months duration, and had not obtained lasting improvement from other forms of therapy, were treated by stimulating nine acupuncture points using a low powered infrared laser (300 microW, 904 nm). The treatments were performed weekly, and consisted of stimulating each point for 2 minutes with a pulse frequency of 360 pulses per second. After completion of a mean of 11 treatments, clinical signs of back pain were alleviated in 10 of the 14 horses, there was no change in three, and one was lost to follow-up. Of the 10 horses who were training and competing, four won. One year after treatment was discontinued, 9 of these 10 horses continued to perform at a standard acceptable to the owner.  相似文献   
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228.
Two scapulohumeral arthrotomy techniques were evaluated and compared in 10 normal, young adult greyhounds. A caudolateral approach with craniodorsal retraction of the teres minor muscle (no-tenotomy) and a craniolateral approach with tenotomy of the infraspinatus tendon were each performed unilaterally in 5 dogs. The dogs were evaluated using force plate gait analysis, lameness evaluation, radiography, and goniometry for 5 weeks and then euthanatized. Tenotomy sites and sections of the humeral articular cartilage were collected from shoulder joints that had been operated on and examined microscopically. The same surgical approach was then performed on the contralateral shoulder in the cadavers and exposure of the humeral articular cartilage was measured using planimetry. Peak vertical force applied to the operated limbs in the tenotomy group was significantly less than preoperative levels on day 3 and significantly less than the no-tenotomy group on days 21 and 28. The peak vertical force applied to the operated limbs in the no-tenotomy group was not significantly different from preoperative levels during the study. Scapulohumeral arthrotomy by tenotomy of the infraspinatus resulted in decreased range-of-motion and joint extension compared with joints operated on without tenotomies, but provided significantly greater exposure to the articular surface. Scapulohumeral arthrotomy with craniodorsal retraction of the teres minor muscle did not significantly alter goniometric measurements compared with unoperated joints. Both techniques resulted in similar subjective lameness scores and caused no gross microscopic or radiographic evidence of articular cartilage damage.  相似文献   
229.
Ocular mastocytosis in a horse   总被引:1,自引:0,他引:1  
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230.
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