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151.
A 13-month-old Angus steer was examined with a 6-week history of lethargy, malaise and dribbling urine. Laboratory exam revealed crystalluria and poor renal function. Ultrasound revealed hydronephrosis and hydroureter. Euthanasia was chosen because of a poor prognosis for economic recovery. Necropsy demonstrated numerous calculi causing partial urethral obstruction approximately 25 cm from the end of the penis. Secondary renal changes were confirmed. Urolithiasis occurs commonly in ruminants. Secondary obstruction is usually complete with severe consequences. This is the first report of chronic partial obstructive urolithiasis resulting in endstage renal disease. 相似文献
152.
The objective of these experiments was to examine methods of modifying the fatty acid composition of bovine tissues. In the first experiment, four steers were fitted with duodenal fistulas and were assigned to four diets in a Latin square design. The steers were fed a control diet or the same diet containing 10% high-oleate partially crushed sunflower seeds, serum-coated sunflower seeds, and heat-treated, serum-coated sunflower seeds for 5 d. Samples of digesta and feces were collected on d 5. The inclusion of sunflower seeds (plain or serum-coated) in the diet increased (P less than .05) the digesta concentration of stearate. The percentage of stearate in the digesta and feces was increased (P less than .05) from 51 to 67% and from 64 to 74%, respectively, when steers were fed the untreated sunflower seed. The fecal concentration of oleate was increased (P less than .05) by dietary sunflower seeds in steers that were fed the serum-coated, unheated sunflower seeds. In a second experiment, heifers (four per group) were fed a corn-based control diet or diets containing 10% of high-oleate sunflower oil encapsulated with calcium alginate, either plain, coated with blood meal, or with blood meal integrated into the pellet. After 50 d on treatment, samples of perianal adipose tissue were obtained by biopsy. The fatty acid composition of the adipose tissue was not modified by the inclusion of the encapsulated oleate in the diet. In summary, limited ruminal bypass of sunflower seed oleate was accomplished with sunflower seed but not with encapsulated oleate. 相似文献
153.
An account is given of the methodology for fractionation of cock spermatozoa into head and tail fractions by ultrasonication, followed by sucrose density gradient centrifugation. Quantitative estimates of DNA attested to 89.4% purity of the head fraction and low contamination of tails with heads. Recovery of protein and malic dehydrogenase (MDH) activity, following sperm fractionation, averaged 94.3% and 95.7%, respectively. Contamination of the head fraction with tails, as assessed by MDH assay, was only 4.65%, and the purity of the tail fraction was 91%. Intensive succinic dehydrogenase (SDH) activity was histochemically localised in the separated tail fraction and in the tail portion of intact spermatozoa. However, SDH activity was discernible neither in the head fraction nor in the head of intact spermatozoa. 相似文献
154.
155.
Four procedures were compared for isolation of Staphylococcus aureus from swabbing solutions of teat skin and milking unit liners from commercial dairies. In 2 procedures, 0.1 ml of swabbing solutions were added to either 5 ml Vogel-Johnson or Baird Parker broth media and enriched at 37 degrees C, 4 h. Following enrichment, 0.1 ml culture was transferred to modified Baird-Parker agar and incubated at 37 degrees C, 48 h. In the other 2 procedures, 0.1 ml of swabbing solution was directly placed on either blood or modified Baird-Parker agar plates and incubated at 37 degrees C 48 h. Combining results from all methods, Staphylococcus aureus were isolated from 72 of 913 (7.9%) skin samples, and 34 of 268 liners (12.6%). On average, 43.1% (31/72) of the S. aureus isolates were found by the enrichment in liquid Vogel-Johnson procedure. The average isolation percentage for other methods ranged from 19.4% to 25.0%. Isolation of S. aureus from milking unit liner or teat skin swabbing solutions was approximately twice as likely after enrichment in Vogel-Johnson liquid media as opposed to other methods of isolation. This indicates that enrichment in Vogel-Johnson liquid media improved recovery of S. aureus from swabbing solutions. 相似文献
156.
A condition characterised by the early onset of vestibular deficit and hearing loss was investigated in the dobermann breed of dog. Affected pups showed behavioural signs of head tilt, circling and ataxia and there was a total absence of vestibular response to rotation or caloric stimulation. Severe deafness, as assessed by brainstem auditory evoked response testing, was present by three weeks of age in all affected animals. The inner ears showed a progressive neuroepithelial type of cochlear degeneration with loss of the auditory sensory cells. In the vestibular system, however, there was no equivalent sensory cell loss and the only abnormal feature was the absence or abnormality of the otoconia in some of the affected animals. Pedigree analysis suggested that the condition was inherited as an autosomal recessive trait. 相似文献
157.
A J Dart J R Snyder S J Spier K E Sullivan 《Journal of the American Veterinary Medical Association》1992,201(8):1244-1248
Packed cell volume, total plasma protein, serum sodium, potassium, and ionized Ca2+ concentrations, and blood pH were determined at the time of admission and following surgery in 147 horses with acute abdominal crisis. Horses were allotted to 3 categories on the basis of the surgical lesion: (1) nonstrangulating obstruction of the ascending or descending colon (category A, n = 76), (2) strangulating and nonstrangulating infarction of the cecum or ascending colon (category B, n = 37), and (3) strangulating and nonstrangulating infarction of the small intestine (category C, n = 25). Horses with low serum ionized Ca2+ concentration following surgery were given 23% calcium gluconate (100 to 300 ml) IV to effect, and ionized Ca2+ concentration was determined following treatment. The serum ionized Ca2+ concentrations of horses in categories A, B, and C before and after surgery were lower than our normal laboratory reference range. Prior to surgery, serum ionized Ca2+ concentration measured from horses in category B and C was lower than that in horses in category A. There was no difference in ionized Ca2+ concentration in serum samples obtained before surgery in horses from category B and C, and in serum samples obtained following surgery. There was a decrease in ionized Ca2+ concentration during surgery in horses in category A. There was no change between preoperative and postoperative ionized Ca2+ concentration in the samples obtained from horses in category B and C. After calcium gluconate administration, all horses with low serum ionized Ca2+ after surgery had concentrations within our normal range. Measurement of serum ionized Ca2+ in horses with an acute abdominal crisis is recommended.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
158.
Effect of dietary protein content on episodic growth hormone secretion and on heat production of male broiler chickens. 总被引:1,自引:0,他引:1
1. The effect of the crude protein content (200 and 150 g/kg) of isoenergetic diets on episodic growth hormone (GH) release and on heat production was investigated in male broiler chickens. 2. Decreasing the crude protein content of isoenergetic diets from 200 g/kg (HP diet) to 150 g/kg (LP diet) resulted in depressed body weight gain, impaired food conversion efficiency and increased abdominal fat deposition. 3. The pattern of growth hormone secretion was markedly affected by dietary treatment. Broiler chickens fed on the LP diet had higher overall mean, amplitude, baseline and peak frequency than the HP chickens. 4. The LP chickens produced more heat per unit of metabolic body weight than the HP chickens. 5. The hypothesis relating the pattern of GH secretion to protein conversion efficiency was corroborated. 相似文献
159.
A. S. TURNER BVSc MS Diplomate ACVS G. W. TROTTER DVM MS Diplomate ACVS B. E. POWERS DVM PhD 《Veterinary surgery : VS》1995,24(4):308-314
Bilateral palmar and plantar digital neurectomies were completed in 10 horses (a total of 80 neurectomies) using one of three methods: (1) simple transection (guillotine method); (2) epineural capping; (3) n-butyl cyanoacrylate injected into the epineural sheath to act as a nerve sealant. Horses were regularly evaluated clinically for tenderness in and around the surgical site, as well as skin sensation at the coronary band in the heel region, during the 12-week course of the study. None of the surgical sites exhibited any signs of drainage or infection. Horses were then euthanatized, the nerve stumps were dissected from surrounding tissues, and the length and width of the tissue mass that had formed on the end of the nerve was recorded. Longitudinal and transverse sections of the nerve endings were examined histologically for numbers of proliferating axon sprouts (neuroma formation); whether the axons had penetrated the epineurium; degree of Schwann cell proliferation; degree of chronic inflammation; extent of foreign body reaction; extent of retrograde degeneration of the nerve bundles; and amount of fibro vascular proliferation. The proportion of legs exhibiting tenderness or heel sensation did not differ significantly between the three different treatments at any of the six different times they were examined. There was no difference between the three treatments in the length or width of the fibrous tissue scar on the ends of the nerves or in the number of sprouting axons from the ends of the nerves. Of 80 nerves examined, only two nerves were not confined to the epineurium. Both these nerves had been treated by simple transection. Statistically there was more chronic inflammation and foreign body reaction in the acrylic treated nerves, but no difference in Schwann cell proliferation or retrograde degeneration between the three treatments. There was slightly less fibrovascular proliferation in the transected nerves than in those subjected to epineural capping or acrylic, but the difference was not statistically significant. The use of the tissue adhesive n-butyl cyanoacrylate to prevent the continuous growth of axons after digital neurectomy seems to offer little advantage over more traditional methods of neurectomy. 相似文献
160.
Morphologic changes in the mammary gland of megestrol acetate-treated and untreated cats: a retrospective study 总被引:4,自引:0,他引:4
Abnormal mammary gland growth is a side effect of progestin therapy in some cats. In this retrospective study, the nature and significance of morphologic changes in the mammary gland of 17 megestrol acetate (MA)-treated cats were compared to mammary lesions in 97 untreated cats. Fourteen out of 17 MA-treated cats had non-neoplastic mammary lesions including fibroepithelial hyperplasia (nine cats), lobular hyperplasia (three cats), and duct ectasia (two cats); whereas three MA-treated cats had mammary neoplasms including one adenoma and two carcinomas. Although MA has been causally linked to mammary cancer in cats, only mammary fibroepithelial hyperplasia was clearly associated with MA therapy in this study. Fibroepithelial hyperplasia occurred in older (average age 8.1 years) neutered male and female cats in the MA-treated group and in younger (average age 2.1 years) female cats in the untreated group. Morphologically, both intraductal and solid fibroepithelial growth patterns were seen. Intraductal fibroepithelial hyperplasia was further subdivided into papillary and circumferential types. An apparent greater association between MA therapy and the intraductal types of fibroepithelial hyperplasia was noted. Furthermore, it appears likely that mammary lobular hyperplasia also is linked to MA therapy. Possible mammatrophic effects of MA and other growth-promoting agents in the cat are discussed. 相似文献