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61.
OBJECTIVE: To compare a recently developed recombinant MSP-5 competitive inhibition ELISA with a card agglutination test for detection of antibodies to Anaplasma marginale and Anaplasma centrale in Australian cattle. MATERIALS AND METHODS: The ELISA was compared with the card agglutination test using 208 sera from cattle in Anaplasma-free herds, 86 sera from cattle experimentally infected with A marginale or A centrale and 757 sera from cattle in areas endemic for A marginale. RESULTS: The specificity of the ELISA, based on testing 208 sera from cattle in Anaplasma-free areas, was 99.5%, and the sensitivities for detection of antibodies to A marginale and A centrale in sera from the experimentally infected cattle were 98.0% and 100%, respectively. For the same sets of sera, the specificity of the card agglutination test was 98.6% and the sensitivities for detection of antibodies to A marginale and A centrale were 98.0% and 100%, respectively. For the 757 sera collected from cattle in areas endemic for A marginale, the agreement between the ELISA and the card agglutination test depended on the positive threshold selected for the ELISA. The maximum achievable agreement was 91.5% (kappa = 0.73; 95% confidence interval 0.66, 0.79). CONCLUSION: We conclude that the competitive inhibition ELISA is a useful alternative to the card agglutination test for detection of A marginale or A centrale infection in cattle. The assay should be particularly useful for epidemiological applications such as prevalence studies and control programs.  相似文献   
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OBJECTIVE: To examine the effects of a dietary humic and fulvic acid complex, FeedMAX 15, on the health, growth rate, feed conversion ratio, and carcase characteristics of feedlot cattle. DESIGN: Cattle, in eight pens of 125 animals each, were fed either a diet containing a humic and fulvic acid complex (FeedMAX 15, FeedMAX Industries, Toowoomba, Queensland) or the same diet without the additive. Control or FeedMAX 15 diets were allocated to each pen at random. Individual cattle were allocated alternately to control or treatment pens based on order of presentation. Comparisons of disease incidence, mortality, feed intake, growth rate, feed conversion ratio, fat depth, dressing percentage, meat colour, fat colour and marbling were made at the conclusion of the feeding period. RESULTS: No differences were found between cattle fed FeedMAX 15 and cattle not fed the additive in entry body weight (P = 0.99), exit body weight (P = 0.91), dressing percentage (P = 0.66), P8 fat depth (P = 0.57), meat colour (P = 0.67), marbling (P = 0.70), all diseases (P = 0.64), bovine respiratory disease (P = 0.91), or mortalities (P = 1.0). Cattle fed FeedMAX 15 reached the market specifications for body weight and fat depth in fewer mean days (P = 0.0001), had a greater average daily gain (P = 0.05), a lower feed conversion ratio (P = 0.05) and whiter fat (P < 0.0001). CONCLUSIONS: Feeding the humic and fulvic acid complex, FeedMAX 15, at 0.055 g per kg body weight per day, can increase growth rate and feed conversion efficiency in feedlot cattle.  相似文献   
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The main goal of this study was to assess the usefulness of two imaging modalities, namely the B‐mode and colour Doppler sonography, and serum progesterone (P4) concentrations for determining the ovarian response in superovulated ewes. Twenty‐four sexually mature Santa Inês ewes underwent the superovulatory treatment consisting of eight injections of porcine FSH (total dose of 200 or 133 or 100 mg; =  8 ewes/total dose) given at 12‐hr intervals and initiated 48 hr before CIDR ® (Pfizer Inc., Auckland, New Zealand) removal. Six days after natural mating, the ovaries of all donor ewes were visualized and examined with transrectal ultrasonography and then with videolaparoscopy to identify and enumerate corpora lutea (CL ) and luteinized unovulated follicles (LUF s). Jugular blood samples were collected just prior to ovarian examinations. The total number of CL (=  .78 and 0.83, <  .0001) and LUF s (=  .74 and 0.90, <  .0001) enumerated using the B‐mode and colour Doppler ultrasonographic technique, respectively, were correlated with that ascertained by videolaparoscopy. Circulating concentrations of P4 were related directly to the number of healthy CL (=  .73, =  .0002) and inversely to the number of prematurely regressing CL (= ?.46, =  .03), but the accuracy of predicting the number of short‐lived CL with serum P4 concentrations was very poor. The present results indicate that ultrasonographic imaging and serum P4 measurements on the day of embryo recovery are useful indicators of total/normal CL numbers and both ultrasonographic techniques can be used to quantify LUF s in superovulated ewes.  相似文献   
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In the current survey, there was no clear evidence that GM (genetically modified) crops are higher yielding than those conventionally bred&lt;fnoteref rid="fn1"&gt;1&lt;/fnoteref&gt;. Furthermore, there were no trials to support valid comparisons of yield per se. This article investigates GM crop yields, introducing the importance of hybrid vigour and a non-stress environment for higher percentage heritability selection and therefore more productive conventional plant breeding and improved crops. GM technology and crops are compared with proven plant breeding methods, with respect to hybrid vigour and the economic viability of both systems. These proven methods of plant breeding are (1) traditional landrace cropping, (2) conventional Mendelian breeding and (3) Isolection Mendelian breeding, and are also considered historically.  相似文献   
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Objective To compare the postoperative analgesic and sedative properties of buprenorphine and morphine in cats. Study Design Prospective, randomized, blinded study. Animals Thirty‐two domestic cats undergoing surgery. Methods Cats received pre‐anaesthetic medication with acepromazine (0.05 mg kg?1) given intramuscularly and were randomly allocated to group M and given morphine (0.1 mg kg?1) intramuscularly (IM) or to group B and given buprenorphine (0.01 mg kg?1) IM. Anaesthesia was induced with propofol and maintained with halothane in oxygen and nitrous oxide. Pain and sedation scores using visual analogue scales, and heart and respiratory rates, were measured immediately before, and 30, 60, 120, 180, 300 and 420 minutes after anaesthesia. Results Pain scores were significantly lower at 60, 120 and 180 minutes after anaesthesia in group B. Group B also had higher heart rates at 30 minutes. There were no other statistically significant differences between the groups. Clinical relevance Buprenorphine (0.01 mg kg?1) appeared to provide better postoperative analgesia than morphine (0.1 mg kg?1) and may also have a longer duration of action.  相似文献   
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Protein hydrolysates from low-value underutilised fish species are potential sources of high-quality dietary protein and health enhancing peptides. Six blue whiting soluble protein hydrolysates (BW-SPH-A_F), generated at industrial scale using different hydrolysis conditions, were assessed in terms of their protein equivalent content, amino acid profile and score and physicochemical properties in addition to their ability to inhibit dipeptidyl peptidase IV (DPP-IV) and stimulate the secretion of insulin from BRIN-BD11 cells. Furthermore, the effect of simulated gastrointestinal digestion (SGID) on the stability of the BW-SPHs and their associated in vitro antidiabetic activity was investigated. The BW-SPHs contained between 70–74% (w/w) protein and all essential and non-essential amino acids. All BW-SPHs mediated DPP-IV inhibitory (IC50: 2.12–2.90 mg protein/mL) and insulin secretory activity (2.5 mg/mL; 4.7 to 6.4-fold increase compared to the basal control (5.6 mM glucose alone)). All BW-SPHs were further hydrolysed during SGID. While the in vitro DPP-IV inhibitory and insulin secretory activity mediated by some BW-SPHs was reduced following SGID, the activity remained high. In general, the insulin secretory activity of the BW-SPHs were 4.5–5.4-fold higher than the basal control following SGID. The BW-SPHs generated herein provide potential for anti-diabetic related functional ingredients, whilst also enhancing environmental and commercial sustainability.  相似文献   
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