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991.
The present study was designed to determine the effects of supplemental fat or oil rich in oleic acid on the fatty acid profiles (FAP) and physical and sensory traits of pork carcasses. Sixty barrows and gilts were equally distributed among five dietary treatments consisting of a control diet of corn and soybean meal and four similar test diets that contained 10% animal fat (45.3 oleic), safflower oil (72.1 oleic), sunflower oil (80.9 oleic) or canola oil (57.7 oleic). The pigs were slaughtered after being fed these diets for 90 d at about 100 kg live weight. Carcass traits, FAP and sensory properties were evaluated for each treatment. First-rib fat thickness, ham muscling score and longissimus muscle areas were not different (P less than .05), but last-rib fat thickness was increased (P less than .05) with the supplemental dietary fat or oils. No differences existed for marbling scores, lean color, firmness or texture scores between the controls and pigs supplemented with either animal fat or safflower oil. However, pigs supplemented with sunflower or canola oil had lower marbling scores, lean color, firmness and texture scores. Fat became softer and more oily (P less than .05) with the supplemental dietary safflower, sunflower and canola oils. Sensory evaluation (loin chops) showed no differences (P less than .05) in sustained juiciness, tenderness or flavor intensity evaluations among treatments. However, the pigs fed canola oil had lower (P less than .05) flavor quality scores or overall palatability evaluations. Chops from the pigs fed canola oil also had 46% more off-flavors than all other treatments.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
992.
The study describes the profiles of culled cows in order to assess the possible contribution to economic losses due to health disorders. Data regarding dates of birth, final calving and culling, parity at culling, milk yield at the two first test-days of the final lactation and reason(s) for culling were collected in a 5-year survey, carried out from 1989 to 1994 in 84 commercial Holstein farms in western France. Polytomous logistic regression was used to assess the relationship between parity, calving-to-culling interval, milk yield and eight groups of primary culling reasons (i.e. udder disorders; infertility or reproductive disorders; lameness or foot/leg defects; emergency culling reasons; other health disorders; low milk yield; sales for dairy purpose; and other voluntary culling reasons). Out of a total of 5133 culled cows, the proportions of culls, for each of these groups of reasons, were 12.4, 28.4, 2.7, 3.9, 4.6, 16.7, 5.9, and 25.4%, respectively. Cows culled for udder disorders left the herd earlier in lactation and were more frequently at parities 4–6 than cows culled for voluntary reasons. In contrast, cows culled for infertility were younger and culled later within lactation. They were also higher yielding cows than those culled for other reasons. Cows culled for lameness were similar to those of the voluntarily culling group. Cows culled for emergency reasons were more frequently younger cows in early lactation. Cows culled for other health disorders left the herd early in lactation, but at a higher parity than the voluntarily culled cows. These results suggest that most of the culls related to health could be contributing to economic loss. However, special priority should be given to reduce culling for reproductive problems, which is the most costly exit reason.  相似文献   
993.
The antigen detection enzyme immunoassay (AgELISA) in conjunction with parasitological examination of blood were used to study the enzootic situation of cameline trypanosomiasis in mid-Eastern Sudan. A one year survey showed that the infection is endemic among pastoral camels with a prevalence of 5.4% based on parasitological examination and 31.3% based on AgELISA. The infection rate was higher during the dry period (November to May) than the wet season. Young camels had a much lower infection rate as detected by parasitological techniques, but not with AgELISA. A lower prevalence of infection was detected by buffy coat technique (BCT) in herds of camels raised by nomads compared with those kept by agropastoralists and in camels located in the southern districts of mid-Eastern Sudan.  相似文献   
994.
995.
In this work the antiviral activity of 20 dehydroepiandrosterone (DHEA) analogs with different substituents at positions C-3, C-15, C-16 and C-17 were evaluated against vesicular stomatitis virus (VSV) in Vero cell cultures. The selectivity indexes (SI) obtained with DHEA and epiandrosterone (EA) were 50 and 72.6, respectively. The work showed that the compounds 21-norpregna-5,17(20)-dien-3β,16α-diyl-diacetate, 17,17-ethylendioxyandrostan-5,15-dien-3β-ol and 3β-hydroxypregn-17(20)-en-16-one had higher SI values than ribavirin, which was used as a reference drug. The antiviral mode of action of DHEA was also investigated against VSV replication in Vero cells, and time of addition experiments showed that DHEA mainly affected a late event in the virus growth cycle. Analysis of RNA and protein synthesis indicated that DHEA adversely affected positive strand RNA synthesis and viral mature particle formation.  相似文献   
996.
Diagnosis of major endemic bovine parasitic diseases in sub-Saharan Africa such as trypanosomosis, theileriosis, anaplasmosis, babesiosis and cowdriosis is increasingly relying on clinical diagnosis due to deterioration of veterinary services and laboratory facilities. Pyrexia is a common clinical feature of aforementioned diseases whose detection relies on measurement of rectal temperature. The research undertaken in this study was aimed at assessing the effects of diurnal changes and variable coat colour of indigenous Nkedi Zebu cattle on the diagnostic value of rectal temperature under tropical conditions. The results revealed that variation in rectal temperature was significantly influenced by time of day it was taken and by the coat colour of the Nkedi Zebu cattle (P < 0.001). Rectal temperature experienced diurnal changes: steadily rising to reach a peak at 17.00 h before declining. The mean rectal temperature of unhealthy cattle was significantly higher (P < 0.05) than that of the healthy ones only between 13.00 and 17.00 h of the day. During which period the proportion of unhealthy cattle having a rectal temperature of 39.4 °C or higher was significantly higher than that of healthy ones (P < 0.001). Regarding the variable coat colour of indigenous breeds, rectal temperature among cattle of different coat colours was significantly different (P < 0.05). In conclusion it is important to consider diurnal changes in rectal temperature and differences due to variable coat colour of indigenous African breeds when measuring rectal temperature for assessing pyrexia, during clinical diagnosis of bovine trypanosomosis and tick-borne diseases that are endemic in many countries in sub-Saharan Africa.  相似文献   
997.
The purpose of this study was to determine whether intravaginal prostaglandin F2 alpha (PGF2 alpha) would be effective for the treatment of metritis or pyometra in the bitch. Seventeen bitches with metritis or pyometra were treated with PGF2 alpha. Prostaglandin F2 alpha (150 micrograms/kg body weight) was administered once or twice daily by infusing 0.3 ml per 10 kg body wt into the vaginal lumen. Bitches were also treated with amoxicillin (15 mg/kg body wt/48 h) and/or gentamicin (4 mg/kg body wt/day) administered as intramuscular (i.m.) injections. Fifteen bitches were treated successfully with intravaginally administered PGF2 alpha for 3 to 12 days and with intramuscularly administered antibiotics for 4 to 12 days. Success of treatment was judged by cessation of vaginal discharge, the absence of fluid in the uterus as determined by ultrasonography, and the overall health status of the animal. As two bitches with pyometra showed clinical deterioration in spite of medical treatment, ovariohysterectomy was performed after the first and the second treatment, respectively. No side effects (salivation, vomiting, diarrhoea, hyperpnoea, ataxia, urination, anxiety, pupillary dilatation followed by contraction) were observed after PGF2 alpha treatment. The disease did not recur during the subsequent oestrous cycles within 12 months after the initial treatment. The results demonstrate that intravaginal administration of PGF2 alpha was effective in 13 dogs (86.6%) with metritis or pyometra, and caused no side effects. Although the study was based on a relatively small number of cases, it is concluded that prostaglandin F2 alpha can be a useful means of treating bitches with metritis or pyometra. However, in severe cases of pyometra ovariohysterectomy is needed.  相似文献   
998.
Conservation of nitrogen in cattle feedlot waste with urease inhibitors.   总被引:3,自引:0,他引:3  
Feedlot cattle normally retain less than 20% of their dietary nitrogen intake. Sixty to 80% of the nitrogen excreted is normally lost through volatilization of ammonia, which is primarily generated from urea. This loss of ammonia nitrogen pollutes the environment and creates an unfavorable ratio of nitrogen to phosphorous (N:P) in the waste for crop growth. Two urease inhibitors, cyclohexylphosphoric triamide (CHPT) and N-(n-butyl) thiophosphoric triamide (NBPT) were evaluated for their ability to reduce the rate of urea hydrolysis in beef cattle feedlot pens. Initially, a total of six pens were used, two pens per treatment, with approximately 70 cattle per pen, and a single topical application of CHPT or NBPT at 20 mg/kg of manure. Essentially no urea was found in untreated pens. However, with CHPT treatment, 2 g of urea/kg of dry manure accumulated by d 4, and all gradually disappeared by d 11; NBPT conserved 3 and 3.5 g of urea/kg by d 4 and 9, respectively, and it had disappeared by d 14 (treatment [trt] x day, P = .003). A second study involved application of NBPT weekly for 6 wk. This caused urea to accumulate to a peak concentration of 17 g/kg of manure by d 30 (trt x day2, P = .001). Once the treatment was stopped the urea concentration began to decrease. When the NBPT was applied weekly, the concentration of ammonia in the waste was less for the treated pens (trt x day, P = .01), the total nitrogen was greater (trt x day, P = .04), pH tended to be lower (trt x day, P = .10), and the total volatile acids were not different (trt x day, P = .51) from untreated pens. We concluded that urease inhibitors could be used to control ammonia emissions from animal wastes, prevent environmental damage, and produce a more balanced (N:P) fertilizer from manure.  相似文献   
999.
The objective of this study was to investigate in mares the effect of parturition on plasma and milk levels of retinol, beta-carotene, alpha-tocopherol and cholesterol over 12 weeks around parturition. In blood plasma of horses around parturition an increase of all these components was observed. This increase was most impressive in beta-carotene (P<0.05) and less pronounced for vitamin E, vitamin A and cholesterol. The magnitude of increase around parturition corresponded well with the magnitude of accumulation in colostrum; levels of beta-carotene in colostrum were 65 times higher compared to mature milk while vitamin A, vitamin E and cholesterol were only 3 to 8 times higher. Beta-carotene concentrations in colostrum were positively correlated with corresponding plasma levels (r = 0.9; P<0.001). Reasons for the increase in plasma beta-carotene around parturition may include an improved absorption of carotene and/or reduced conversion into vitamin A as well as mobilisation from tissue storages or a reduced uptake in tissues other than the mammary gland. In conclusion, the results may point to possible component- and species-specific differences involved in the transfer of fat-soluble vitamins, beta-carotene and cholesterol from blood plasma into colostrum.  相似文献   
1000.
Two enzyme-linked immunosorbent assays (ELISA) for the determination of homidium in serum of treated cattle have been developed and evaluated. One is a direct competition (Assay 1) and the other an indirect competition assay (Assay 2). Both assays are highly sensitive with a limit of detection of 0.1 ng homidium per mL serum. Homidium levels were measurable in serum of cattle for over 2 months following administration of a single intramuscular (i.m.) dose at 1 mg/kg bodyweight. The level of sensitivity afforded by these assays makes them potentially useful tools in the pharmacokinetic evaluation of homidium and for investigating drug resistance or causes of drug failure. Assay 2 was chosen as being most suitable for further studies.  相似文献   
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