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1.
Electromyography (EMG) was used to detect myotonic discharges in Quarter Horse breeding stock and to follow the results of mating horses with hyperkalemic periodic paralysis (HPP). The studies were performed on two brood mare farms. A total of six breeding stock showed myotonic discharges and 15 were nonmyotonic. Myotonic discharges were seen in five of six horses belonging to the blood line previously implicated as being predisposed to HPP. Two of these horses had shown clinical signs of HPP. Only one of 15 breeding horses unrelated to the HPP predisposed blood line showed myotonic discharges. When both parents were non-myotonic on EMG than the F1 generation (n = 6) were also nonmyotonic. When a stallion with HPP and myotonic discharges was mated to eight nonmyotonic mares over a six year period half the animals of the F1 generation (n = 25) showed myotonic discharges. When both parents showed myotonic discharges four F1 offspring were myotonic and two were nonmyotonic on EMG testing. There was no evidence of sex linkage. The results are consistent with an autosomal dominant mode of inheritance. Hyperkalemic periodic paralysis and myotonic discharges on EMG may be different manifestations of the same underlying defect.  相似文献   
2.
A nine year old Hereford crossbred cow with a history of progressive neurological signs was referred to the Western College of Veterinary Medicine, Saskatoon. A large intracranial mass, histologically identified as a schwannoma, was found to be compressing the left brain stem and appeared to have arisen from the left fifth cranial nerve.  相似文献   
3.
We examined 18 horses with clinical signs of chronic obstructive pulmonary disease (COPD) using physical examination, cytological and bacteriological evaluation of bronchoalveolar fluid, and percutaneous lung biopsy. In 16 cases, histological examination of lung tissue confirmed the diagnosis of COPD. Two horses were excluded: one had uncomplicated bacterial pneumonia and in the other a satisfactory lung biopsy could not be obtained. In horses with COPD, the most common historical complaint was coughing, which was reported in 88%. The most frequently detected abnormal finding on physical examination was abnormal lung sounds; these were detected in 69% of horses at rest and in 88% of horses breathing deeply into a bag. A novel finding was that 29% of horses had lung sounds that were quieter than would be expected for the degree of respiratory effort. Horses with COPD had increased percentages of neutrophils and decreased percentages of lymphocytes and macrophages in their bronchoalveolar lavage fluid. Bronchiolar neutrophil infiltration and peribronchiolar mast cell accumulation in lung biopsy tissue had the highest correlation with clinical condition. The severity of pathological changes in biopsies of lung did not predict whether the horse would die in the two to four year follow-up period. Horses that died in the follow-up period were more severely affected clinically at initial presentation than horses that were alive at the end of the follow-up period.  相似文献   
4.
A method for the separation of leucocytes from bovine blood and its separation into lymphocyte and granulocyte fractions is described. The method, involving flash lysis of the erythrocyte population, was found to yield large numbers of viable cells suitable for maintenance in tissue culture medium and hence of value in immunological studies.  相似文献   
5.
Diarrhea is a common occurrence in neonatal calves. Several veterinary probiotics claiming to prevent or treat calf diarrhea are available, but have not been well studied. This study assessed the capability of Lactobacillus rhamnosus strain GG (LGG) to maintain viability in the gastrointestinal tract of calves. We also determined whether LGG can be administered in an oral rehydration solution (ORS) without compromising the efficacy of the ORS or the viability of LGG, and whether LGG produces D-lactate or not. To investigate the intestinal survival of LGG, 15 calves were randomized into 3 groups and LGG was administered orally with their morning milk feeding on 3 consecutive days at a low (LD), medium (MD), or high (HD) dosage. Fecal samples were collected on days 0 (control), 1, 2, 3, 5, and 7 and incubated for 72 h on deMan, Rogosa, Sharpe agar. Twenty-four hours after the 1st feeding, LGG was recovered from 1 out of 5 calves in the LD group, 4 out of 5 calves in the MD group, and 5 out of 5 calves in the HD group. To determine if LGG caused the glucose levels in the ORS to drop below effective levels, 1.5 L of the ORS was incubated with LGG for 2 h at 37 degrees C and the glucose concentration was measured every 20 min using a glucose meter. This ORS was then further incubated for 10 h and aliquots analyzed by high performance liquid chromatography to determine if D-lactate was produced by LGG. Glucose concentrations did not change over the 2 h of incubation, and no D-lactate was produced after 48 h. The LGG maintained viability in ORS. Therefore, this study demonstrated that LGG survives intestinal transit in the young calf, produces no D-lactate, and can be administered in an ORS.  相似文献   
6.
The purpose of this article is to provide a review of the current knowledge and opinions about the epidemiology, clinical findings (including sequelae), diagnosis, treatment and monitoring of equine pituitary pars intermedia dysfunction, particularly in the Australian context. This information and the recommendations provided will assist practitioners in making informed decisions regarding the diagnosis and management of this disorder.  相似文献   
7.
The object of this study was to develop a simple method for accurately calculating the volume of bovine claws under field conditions. The digits of 30 slaughterhouse beef cattle were examined and the following four linear measurements taken from each pair of claws: (1) the length of the dorsal surface of the claw (Toe); (2) the length of the coronary band (CorBand); (3) the length of the bearing surface (Base); and (4) the height of the claw at the abaxial groove (AbaxGr). Measurements of claw volume using a simple hydrometer were highly repeatable (r(2)= 0.999) and could be calculated from linear measurements using the formula:Claw Volume (cm(3)) = (17.192 x Base) + (7.467 x AbaxGr) + 45.270 x (CorBand) - 798.5This formula was found to be accurate (r(2)= 0.88) when compared to volume data derived from a hydrometer displacement procedure. The front claws occupied 54% of the total volume compared to 46% for the hind claws.  相似文献   
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Thirty-six dehydrated diarrheic neonatal calves were used to study the effects of various alkalinizing compounds on acid-base status, the changes in central venous pressure (CVP) in response to rapid IV infusion of large volumes of fluid, and the correlation of acid-base (base deficit) status, using a depression scoring system with physical determinants related to cardiovascular and neurologic function. Calves were allotted randomly to 4 groups (9 calves/group). Over a 4-hour period, each calf was given two 3.6-L volumes (the first 3.6 L given in the first hour) of a polyionic fluid alone (control group) or were given the polyionic fluid with sodium bicarbonate, sodium L-lactate, or sodium acetate added (50 mmol/L). Acid-base status, hematologic examination, and biochemical evaluations were made immediately before infusion of each fluid (at entry) and after 3.6, 4.8, and 7.2 L of fluid had been given. Compared with control values, bicarbonate, lactate, and acetate had significantly greater alkalinizing effects on pH (P less than 0.01) and base deficit (P less than 0.01) after 3.6, 4.8, and 7.2 L of fluid were given. Bicarbonate had the most rapid alkalinizing effect and induced greater changes in base deficit (P less than 0.01) than did acetate or lactate at each of the 3 administered fluid volumes evaluated. Acetate and lactate had similar alkalinizing effects on blood. Rehydration alone did not improve acid-base status. The CVP was elevated in 10 (28%) of the 36 calves after 1 hour of fluid (3.6 L) administration, but significant differences in body weight, PCV, and clinical condition or depression score at entry were not found between calves with elevated CVP and those with normal CVP.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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