Pleistocene extinction of genyornis newtoni: human impact on australian megafauna     

GH Miller  JW Magee  BJ Johnson  ML Fogel  NA Spooner  MT McCulloch  LK Ayliffe 《Science (New York, N.Y.)》1999,283(5399):205-208

More than 85 percent of Australian terrestrial genera with a body mass exceeding 44 kilograms became extinct in the Late Pleistocene. Although most were marsupials, the list includes the large, flightless mihirung Genyornis newtoni. More than 700 dates onGenyornis eggshells from three different climate regions document the continuous presence of Genyornis from more than 100,000 years ago until their sudden disappearance 50,000 years ago, about the same time that humans arrived in Australia. Simultaneous extinction of Genyornis at all sites during an interval of modest climate change implies that human impact, not climate, was responsible.  相似文献   

The Last Tasmanian Tiger, the history and extinction of the thylacine     

BJ Coman 《Australian veterinary journal》2000,78(12):856-856

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An examination of potential indices of fasting time in commercially slaughtered sheep   总被引：1，自引：0，他引：1  

P D Warriss  E A Bevis  S N Brown  J G Ashby 《The British veterinary journal》1989,145(3):242-248

A total of 215 market lambs was slaughtered either directly off grass or after 12, 24, 36, 48 or 72 h from food withdrawal. They had access to water at all times. Half the animals were given a moderate exercise and were subjected to venepuncture about 0.5 h before slaughter. Samples of blood were collected at exsanguination and samples of liver and muscle subsequently removed during carcass dressing. Blood packed cell volume and the concentrations of plasma glucose, lactate, free fatty acids, beta-hydroxybutyrate and total protein, and glycogen in liver and muscle, were examined as potential indices of fasting time. Fasting caused significant changes in all parameters but only beta-hydroxybutyrate increased progressively with longer food-withdrawal times and was unaffected by exercise or the stress of venepuncture. The pattern of response to fasting could be described by an equation of the Gompertz form. Sex of animal did not affect fasting responses but origin of blood (venepuncture or at exsanguination) influenced absolute levels of all the measured blood components except total plasma protein.  相似文献   

Transport and lairage times of lambs slaughtered commercially in the south of England     

P D Warriss  E A Bevis  C S Young 《The Veterinary record》1990,127(1):5-8

The times spent in transport and lairage by 124,036 lambs slaughtered in two plants in the south of England were recorded. About half of them travelled for up to 120 km, taking up to four hours, and three-quarters travelled not more than 300 km, the journeys taking up to about six hours. Bimodal frequency distributions of lairage time were apparent; overall one third of the lambs spent up to four hours in lairage but more than 40 per cent were kept for longer than 14 hours, while they were held overnight. Early season lambs tended to travel shorter distances to slaughter and spent less time in lairage than late season lambs. The average total times spent in transit and lairage were 22.3 hours and 13.3 hours at the two plants.  相似文献   

Effect of the angle of slope on the ease with which pigs negotiate loading ramps.   总被引：1，自引：0，他引：1  

P D Warriss  E A Bevis  J E Edwards  S N Brown  T G Knowles 《The Veterinary record》1991,128(18):419-421

In experiments to investigate the time taken by pigs to negotiate ramps with different slopes it was found that they ascended with greater facility than they descended. Between 0 degrees and 20 degrees, the slope appeared to have little effect on the time taken to ascend or descend. Above 20 degrees the time taken to ascend increased linearly. The relationship between the time taken to descend and the slope above 20 degrees was biphasic with times increasing substantially above 35 degrees. There were also differences between the times taken on different days but no evidence of habituation. Pigs took longer to climb steeper ramps with wider spaces between cleats but there was no significant effect on the time taken to descend.  相似文献   

Dilated cardiomyopathy in an American Cocker Spaniel with taurine deficiency     

BJ GAVAGHAN  MD KITTLESON 《Australian veterinary journal》1997,75(12):862-868

An American Cocker Spaniel with low plasma taurine concentration (< 2 nmol/mL) was presented with dyspnoea associated with pulmonary oedema and a left ventricular shortening fraction of 9%. Emergency therapy with furosemide, dobutamine, nitroglycerine and oxygen supplementation led to a good response. Chronic therapy was started with enalapril, furosemide, digoxin and taurine. Improvement in all echocardiographic indices were noted over a 22 week follow-up, most notably an increase in left ventricular shorteningfraction to 20%, a decrease of E-point septal separation from 14 mm to 7 mm and marked left ventricular remodelling. This degree of improvement in myocardial function may represent a direct link between dilated cardiomyopathy in the American Cocker Spaniel andplasma taurine deficiency. Alternatively, this response may reflect a breed-related cardiomyopathy with a natural history and therapeutic response not commonly seen in the morecommon large breed cardiomyopathy presentations.  相似文献   

Squamous cell carcinoma of the pharyngeal wall in a horse     

JC TUCKEY  BJ HILBERT  S. BEETSON†  A. ADKINS† 《Australian veterinary journal》1995,72(6):227-227

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Bacterial inhibitory residues in pigs fed mouldy grain     

KC WILLIAMS  BJ BLANEY  H. MAWHINNEY 《Australian veterinary journal》1992,69(2):38-39

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Protoporphyria in Limousin cattle     

PJ HEALY  L CAMILLERI  V POULOS  KG HART  BJ KEMP  RE MOORE  J DOOLEY  M WARNER 《Australian veterinary journal》1992,69(6):144-145

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Polymorphism of the Melatonin Receptor Genes and its Relationship with Seasonal Reproduction in the Gulin Ma Goat Breed     

P Lai  BY Zhang  PQ Wang  MX Chu  WJ Song  BJ Cai 《Reproduction in domestic animals》2013,48(5):732-737

Melatonin is thought to be the main molecule that transmits the signal of seasonal change to the neuroendocrine system in seasonal breeding species. Melatonin exerts its effects through specific melatonin receptors, MTNR1A and MTNR1B. In the present study, six native goat breeds in China and one introduced goat breed were analysed to investigate the relationship between the genetic polymorphism of receptor genes and seasonal reproduction. Sequencing results showed that there were five polymorphic mutations in the MTNR1A gene and two in the MTNR1B gene. In the MTNR1A gene, genotypes AA, AB and BB for 424C>T and genotypes CC, CD and DD for 589C>A were observed in these goat breeds. In all six native goat breeds, only genotype AA was detected. In the MTNR1B gene, genotypes EE, EF and FF for 1179G>A and genotypes GG, GH and HH for 1529A>G were detected. However, in Gulin Ma goats, the genotypes EE and HH were not found. Moreover, the base of G at position 1179 and A at position 1529 were linked (By Arlequin ver 3.1, Zoological Institute, Berne, Switzerland, http://cmpg.unibe.ch/software/arlequin3 ,D′ = 0.7496, r² = 0.4421, χ² = 489.8679, p = 0.000). Among these mutations, no amino acid change was found in MTNR1A, while both of the mutations in MTNR1B gene caused amino acid changes of R222H and S339G, respectively. The structural analysis showed that the R222H mutation occurred in the first amino acid residue of the third cytoplasmic loop, and the S339G mutation was located in the carboxyl terminus of the protein. In terms of seasonal breeding, all the genotypes we detected showed a similar kidding frequency distribution trend with a higher frequency in May–August than in January–April and in September–December. This suggests that the relationship between the polymorphisms in the MTNR1A and MTNR1B genes and seasonal breeding could not be established.  相似文献