Production of Lambs After the Transfer of Fresh and Cryopreserved in vitro Produced Embryos from Prepubertal Lamb Oocytes and Unsorted and Sex-sorted Frozen-thawed Spermatozoa     

KM Morton  SL Catt  FK Hollinshead  WMC Maxwell  G Evans 《Reproduction in domestic animals》2004,39(6):454-461

Cumulus-oocyte complexes from hormone-stimulated 3-4-week-old (n=43) and 6-7-week-old (n=12) prepubertal lambs were matured in vitro and incubated with unsorted, or X- or Y-spermatozoa separated with a high-speed cell sorter (SX MoFlo)frozen-thawed. Presumptive zygotes were then cultured to the blastocyst stage, and transferred to recipients fresh or after cryopreservation (frozen). Oocyte cleavage was higher (p <0.05) with unsorted (515/926, 55.6%) than X- or Y-spermatozoa (261/672, 38.8% and 229/651, 35.2%, respectively) and blastocyst formation (% zygotes) by Day 9 of in vitro culture was lower (p <0.05) for X- (102/261, 39.1%) than unsorted spermatozoa (249/515, 48.3%), but did not differ between Y-spermatozoa (103/229, 45.0%) and unsorted spermatozoa, or between X- and Y-spermatozoa (p >0.05). For fresh embryos, survival to term was 50.0% (3/6) for unsorted, 0.0% (0/6) for X- and 16.7% (1/6) for Y-spermatozoa-derived embryos (p >0.05), and for frozen embryos was 4.0% (2/50) for unsorted, 9.1% (2/22) for X- and 2.9% (1/34) Y-spermatozoa-derived embryos (p >0.05). Of the two lambs born from X-spermatozoa-derived embryos, one was female (50%), and from the two Y-spermatozoa-derived lambs, both were male (100%), demonstrating that lambs can be produced after the transfer of fresh and cryopreserved IVP embryos derived from prepubertal lamb oocytes and frozen-thawed sex-sorted sperm.  相似文献   

Effects of feeds on flavor of red meat: a review   总被引：3，自引：0，他引：3  

S L Melton 《Journal of animal science》1990,68(12):4421-4435

The effects of diet ingredients on red meat flavor are dependent on the type of diet, and, to a large extent, on the species: pork, mutton or lamb and beef. Sensory analysis of meat flavor has been used in most of the studies on the effects of feeds on meat flavor. In general, high-energy grain diets produced a more acceptable or a more intense flavor in red meats than low-energy forage or grass diets. Feeding pigs unsaturated fats increases the unsaturation in pork fat but results in only minor changes in pork flavor. Sheep must be fed protected, unsaturated fats in order to increase the unsaturation in their fat to be similar to pork fat. This increased unsaturation results in a greater flavor change in lamb or beef than in pork. Several dietary ingredients such as fish products, raw soybeans, canola oil and meal, and pasture grasses cause undesirable flavors in red meat. Analyses of lamb and beef produced on different diets have shown that type of feed affects the concentration of many flavor volatile compounds. However, only a few studies have quantified the volatiles of beef and lamb produced on different diets, and no reports of studies were found in which the volatiles of pork produced on different diets had been investigated. Hence, the importance of these changes in volatile concentration to meat flavor has not been determined.  相似文献   

Nonenzymatic browning of lactose and caseinate during dry heating at different relative humidities     

Pan GG  Melton LD 《Journal of agricultural and food chemistry》2007,55(24):10036-10042

Dry mixtures of lactose and caseinate were heated at 60 degrees C for up to 96 h at different relative humidities (RHs) ranging from 29 to 95%. The resulting nonenzymatic browning was studied by determining lactulosyl lysine formation in the caseinate (as measured by the conversion to furosine), amount of reacted lactose, loss of lysine, color formation, and fluorescent intensity. For each measurement, the maximum reaction occurred at intermediate RHs. While there is general agreement between the results obtained by different methods, discrepancies are understandable given the complex nature of nonenzymatic browning. It was shown that the degradation of the Amadori product, lactulosyl lysine, increased with RH. Moreover, the Maillard reaction, as opposed to caramelization of lactose, was the major pathway at all RHs. Visible browning occurred when the destruction of Amadori product became dominant, and interactions between sugar fragments and caseinate were not the rate-limiting steps in the nonenzymatic browning.  相似文献   

Development and evaluation of a rapid absorbed enzyme immunoassay test for the diagnosis of Johne''s disease in cattle   总被引：8，自引：0，他引：8  

JC COX  DP DRANE  SL JONES  S. RIDGE†  AR MILNER† 《Australian veterinary journal》1991,68(5):157-160

An absorbed enzyme immunoassay (EIA) test for Johne's disease in cattle was developed in which absorption of cross-reacting antibodies occurred as a rapid reaction in solution rather than overnight with whole organisms and a subsequent centrifugation step. Total test time was reduced to less than 2 h with a minimum of manipulations. The test was evaluated in cattle herds from Johne's disease-endemic and Johne's disease-free regions of Australia. Specificity was 99.8%. Calculations of sensitivity were affected by the history of the herd under test. However, the EIA detected in excess of 80% of animals before onset of clinical disease and 65% of faecal shedders were EIA positive on, or before, first detection of Mycobacterium paratuberculosis in their faeces. The test should aid epidemiological studies and be a useful tool in the management and control of Johne's disease.  相似文献   

Negative findings from serological studies of equine morbillivirus in the Queensland horse population   总被引：2，自引：0，他引：2  

MP WARD  PF BLACK  AJ CHILDS  FC BALDOCK  WR WEBSTER  BJ RODWELL  SL BROUWER 《Australian veterinary journal》1996,74(3):241-243

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Insulin staining of ES cell progeny from insulin uptake     

Rajagopal J  Anderson WJ  Kume S  Martinez OI  Melton DA 《Science (New York, N.Y.)》2003,299(5605):363

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Use of goose red blood cells for detection of infection with psittacine beak and feather disease virus by haemagglutination and haemagglutination inhibition     

N SEXTON  WJ PENHALE  SL PLANT  DA PASS 《Australian veterinary journal》1994,71(10):345-347

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Performance and vanadium content of tissues in sheep as influenced by dietary vanadium   总被引：1，自引：0，他引：1  

I I Hansard SL  C B Ammerman  K R Fick  S M Miller 《Journal of animal science》1978,46(4):1091-1095

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Using 3D animations to teach intracellular signal transduction mechanisms: taking the arrows out of cells     

Buchanan MF  Carter WC  Cowgill LM  Hurley DJ  Lewis SJ  MacLeod JN  Melton TR  Moore JN  Pessah I  Roberson M  Robertson TP  Smith ML  Vandenplas ML 《Journal of veterinary medical education》2005,32(1):72-78

Traditional methods of teaching intracellular biological processes and pathways use figures or flowcharts with the names of molecules linked with arrows. Many veterinary students, presented with such material, simply memorize the names or chemical structures of the molecules and are then likely to forget the material once the examination is completed. To address this problem, the authors designed, created, and field-tested new teaching media that incorporate realistic three-dimensional (3D) animations depicting the dynamic changes that occur in intracellular molecules during cellular activation. Testing found that veterinary students taught using traditional teaching media (e.g., lectures, handouts, textbooks) are proficient in memorizing the names and order of intracellular molecules but unable to appreciate the interactions between these elements or their spatial relationships within cells. In contrast, more than 90% of veterinary students taught using 3D animations not only recall the facts about the intracellular elements but also develop accurate mental images of the interactions among these molecules and their spatial relationships. These findings strongly suggest that the comprehension of complex biological processes by veterinary students can be enhanced by the use of dynamic 3D depictions of these processes in the classroom.  相似文献   

Investigations of an enteric infection of cockatoos caused by an enterovirus-like agent     

SL. WYLIE  DA. PASS 《Australian veterinary journal》1989,66(10):321-324

An enteric infection in cockatoos associated with a 30 nm diameter enterovirus-like agent seen in faeces and intestinal epithelial cells is described. The disease is characterised by intractable, profuse, mucoid diarrhoea, weight loss, dehydration and death. Lesions in the intestine consist of villous atrophy, villous fusion, enterocyte hyperplasia and, in some cases, chronic inflammation. Affected birds so far examined have concurrent psittacine beak and feather disease.  相似文献