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71.
One hundred and six Holstein and Holstein x native cows were inspected before and after slaughter, and liver samples were taken. The fat content of all the liver samples was estimated by an extraction method (Soxhlet). The livers of 29 cows (27%) were classified as fatty. Seventeen of the animals were newly calved, 47 were non-pregnant, 33 were pregnant and 9 were dry, the median values for the fat content of their livers being 60.6, 34.4, 34.7 and 33.8 mg/g, respectively. The median concentration of liver fat in the first group was significantly different from that in each of the other groups (p < 0.01).  相似文献   
72.
The aim of this study was to establish the dose-response relationship between fat intake and heparin-released plasma lipoprotein lipase (LPL) activity in horses. Eight mature trotters were fed 4 rations with different fat levels (3.0, 5.0, 7.7, or 10.8% fat in the dry matter) according to a 4 X 4 Latin square design. The experimental rations consisted of hay and different concentrates; the concentrates and hay were given in a 3:1 ratio on an energy basis. Soybean oil was added to the concentrates at the expense of isoenergetic amounts of glucose. Blood samples were taken at the end of each dietary period, which lasted 3 weeks. Fat feeding was found to increase heparin-released plasma LPL activity in a dose-dependent fashion. When the data from this study and previous studies were combined it was calculated that an increase in fat intake by 1 g/kg dry matter is associated with an increase in LPL activity by 0.98 micromol fatty acid released-mL(-1) x h(-1). Fat feeding raised the plasma concentrations of total cholesterol, high-density lipoprotein cholesterol, and phospholipids. Diet did not have a statistically significant effect on plasma triacylglycerol concentrations. The results are discussed in the light of the possible enhancing effect of fat feeding on the oxidative capacity of skeletal muscle.  相似文献   
73.
Observer variation in diagnosing mild mitral regurgitation in dogs by cardiac auscultation was assessed by having 6 veterinarians with different levels of experience examine 57 Cavalier King Charles Spaniels. Comparisons with color Doppler echocardiography and phonocardiography were made, and the effects of 2 physical maneuvers on the auscultatory findings were evaluated. Using mildly diseased dogs, interobserver agreement in diagnosing the presence or absence of left-sided murmurs ranged from 63% to 88%. The agreement with phonocardiography (range, 53-91%) increased with the amount of observer experience. The 2 most experienced observers could discern soft ejection murmurs from regurgitant murmurs and were able to diagnose 89% of the dogs with regurgitant jets larger than 30% of the left atrial area. In general, less experienced observers diagnosed most jets larger than 50%. In many dogs with small jets, no murmur was found by auscultation and phonocardiography. The audibility of mild regurgitation was significantly reduced in dogs that were difficult to auscultate. Early systolic murmurs were typical of mild regurgitation, whereas holosystolic murmurs typified severe regurgitation. In a few dogs, late systolic murmurs alternated with holosystolic murmurs. Systolic clicks were found phonocardiographically in 18 dogs with mild to moderate regurgitation, but the audibility apparently was low. In many mildly affected dogs, physical maneuvers increased murmur intensity. Thus, some form of dynamic auscultation might facilitate the diagnosis of mild regurgitation. Auscultatory findings in mild regurgitation appear to depend on observer experience, circulatory status, and how difficult the dog is to auscultate.  相似文献   
74.
Sixty-four Wistar rats were divided into 8 equal groups and kept for 36 days in individual boxes. Three of the groups were given full synthetic diets containing various animal fats: beef tallow, pork fat or fish oil. A control group was fed the diets without the fat. The other four groups were fed the same diets with lecithin supplementation. At the end of experiment, sections taken from the liver were stained with haematoxylin–eosin and Sudan III to indicate fat infiltration. Liver enzyme levels, total bilirubin, albumin and two products of lipd metabolism were measured in serum from all the animals. The addition of lecithin to the diets did not influence the level of enzymes in the serum except in rats fed the diet containing beef tallow. A relationship between the type of diet, lecithin supplementation and the total cholesterol concentration in serum was observed. The concentration of HDL-cholesterol was only influenced by lecithin supplementation and that of triglycerides by the type of fat in the diet. The addition of lecithin to the diet was associated with proliferation of Kupffer cells, and an increased number of binuclear cells. Fatty degeneration of hepatocytes was less pronounced in all groups following lecithin supplementation. Lecithin supplementation of the diet did not elicit any pathological lesions and may be considered as a hepatocyte protector. This favourable effect of lecithin was most marked in the group of rats fed the fish oil.  相似文献   
75.
Day-old Lohman broiler chicks (n = 120) were fed on five starting diets for 4 weeks in groups of 24 birds. The starting diets contained 0%, 9%, 18%, 27% and 36% sweet potato tuber as a replacement for maize. From the fifth week, the 120 birds were tested in groups of 30 on four finishing diets containing 0%, 15%, 30% and 45% sweet potato tuber as a replacement for maize. The carcass quality was significantly (p>0.05) improved due to a significant (p>0.05) reduction of abdominal fat in the birds fed on the 45% sweet potato finisher diets. However, the birds on the sweet potato diet continually passed wet dropppings, resulting in a significant (p>0.05) reduction in body weight and feed conversion efficiency. The optimum levels of inclusion of sweet potato in the diets were considered to be 27% and 30% for starting and finishing broiler chickens, respectively. Sweet potato diets may be a remedy for fatty broilers.  相似文献   
76.
With aggregometry, increased platelet activity has been reported in Cavalier King Charles Spaniels (CKCS) without mitral regurgitation (MR). In contrast, dogs with MR have been found to have decreased platelet activity. The purpose of this study was to test an easy bedside test of platelet function (the Platelet Function Analyzer [PFA-100]) to see if it could detect an increase in platelet activity in CKCS without MR and a decrease in platelet activity in CKCS with MR. This study included 101 clinically healthy dogs > 1 year of age: 15 control dogs of different breeds and 86 CKCS. None of the dogs received medication or had a history of bleeding. The PFA-100 evaluates platelet function in anticoagulated whole blood under high shear stress. Results are given as closure times (CT): the time it takes before a platelet plug occludes a hole in a membrane coated by agonists. The CT with collagen and adenosine-diphosphate as agonists was similar in control dogs (median 62 seconds; interquartile interval 55-66 seconds) and CKCS with no or minimal MR (55; 52-64 seconds). The CT was higher in CKCS with mild MR (regurgitant jet occupying 15-50% of the left atrial area) (75; 60-84 seconds; P = .0007) and in CKCS with moderate to severe MR (jet > 50%) (87: 66-102 seconds; P < .0001). CKCS with mild, moderate, and severe, clinically inapparent MR have decreased platelet function. The previous finding of increased platelet reactivity in nonthrombocytopenic CKCS without MR could not be reproduced with the PFA-100 device.  相似文献   
77.
78.
本文主要对麦盖提羊体重与脂肪指标的相关性进行研究分析,并对体重与尾脂重.网油重和肾油重的相关性进行研究分析,认为麦盖提羊活重与胴体重.胴体重与尾脂重,网油重和肾油重之间有不同程度的正相关关系,周岁公母羊活重与胴体重的相关系数分别为0.914和0.997胴体重与尾脂重的相关系数分别为0.56和0.75而且差异极显著.成年公母羊胴体重与尾脂重的相关系数分别为0.73和0.70而且差异极显著.同时指出降低油脂含量和尾脂比重的具体做法,这对麦盖提羊现代育种提供科学的依据.  相似文献   
79.
An 11-year-old American Quarterhorse gelding presented for moderate periorbital swelling and exophthalmia of the left eye. The menace response, and direct and consensual pupillary light reflexes were absent in the left eye. Conjunctival hyperemia, blepharedema, a mydriatic pupil, resistance to retropulsion, and an increased intraocular pressure were present. A soft-tissue mass could be palpated in the left retrobulbar space by pressing onto the orbit over the supraorbital fossa. Incomplete surgical resection of the mass was performed and histopathologic evaluation was consistent with a fibroma. Normal pupillary light reflexes and vision returned following surgery. The mass has not recurred 14 months after surgery.  相似文献   
80.
To study the accuracy and precision of intramuscular fat prediction by ultrasound (USIMF) in lean cattle, prediction models were developed based on 325 pure and crossbred beef and dual purpose bulls originating from I) commercial herds (n = 180) and II) a performance test station (n = 145). The bulls were scanned across the 12th thoracic vertebrae using a Pie 200 SLC scanner. Five images were collected per individual bull for later processing in the lab. After slaughter, a 2.5 cm cross-sectional sample located by the 13th thoracic vertebrae was used for chemical analysis to determine intramuscular fat % (CHIMF; Mean 1.25%, SD 0.6%) at the image site. The data were analysed sequentially involving 1) the Total Dataset, 2) Dataset I and 3) Dataset II. Prediction models were developed separately for each dataset, using stepwise regression procedures. The validation model R2, RMSE, overall mean bias, SEP, rP and rank correlations for CHIMF and USIMF based on the best prediction model (Dataset I) were 0.48, 0.46%, − 0.02%, 0.46%, 0.70 and 0.67, respectively. Further improvement in prediction accuracy can probably be achieved by increasing the size of datasets and the CHIMF variation. The results strongly indicate that ultrasound has potential for IMF prediction in lean cattle, although the value in indirect selection of breeding cattle for meat quality needs to be further evaluated.  相似文献   
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