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11.
12.
To determine the diverse motivations of eastern wild turkey (Meleagris gallopavo) hunters, a self-administered questionnaire was developed and mailed to a sample of 5,000 licensed turkey hunters in Tennessee (response rate = 36%). A cluster analysis yielded three types of respondents in terms of their hunting motivations: social harvesters (44%), experiential harvesters (22%), and social outdoor enthusiasts (34%). Hunters in these segments were then analyzed to compare their support for various hunting regulations. While 61% of Tennessee eastern wild turkey hunters reported to be satisfied with current regulations, harvest-motivated hunters were less receptive to regulations that would limit season lengths or bag limits while socially motivated hunters were more accepting. The hunter groups did not differ in their preference for decentralizing regulations by management zones. Findings from this article may guide wildlife managers in designing socially acceptable regulations.  相似文献   
13.
During the last interglacial, Antarctic climate changed before that of the Northern Hemisphere. Large local changes in precession forcing could have produced this pattern if there were a rectified response in sea ice cover. Results from a coupled sea ice-ocean general circulation model supported this hypothesis when it was tested for three intervals around the last interglacial. Such a mechanism may play an important role in contributing to phase offsets between Northern and Southern Hemisphere climate change for other time intervals.  相似文献   
14.
We report extensive dermatological lesions in three, free-ranging, adult, male swamp wallabies ( Wallabia bicolor ), presented to Taronga Western Plains Zoo wildlife hospital. All three animals were moderately infested with the louse species Heterodoxus ualabati , and two were concurrently infested with a previously undescribed sarcoptiform mite of the genus Diabolicoptes . Histological changes included moderate to marked compact hyperkeratosis, focal deep pyoderma and superficial dermatophytosis. Mild to moderate hyperplastic perivascular and periadnexal dermatitis with marked superficial and follicular hyperkeratosis was evident in the skin of the inguinal region and lateral thigh of the two wallabies infested with the Diabolicoptes species. This is the first report of ectoparasitic dermatitis in free-ranging swamp wallabies and the first report of mites of the genus Diabolicoptes from a macropodid.  相似文献   
15.
Five copper (Cu) sources were studied at pH 2.5, 5.5, and 6.5 to determine how Cu affects phytate phosphorus (PP) hydrolysis by phytase at concentrations up to 500 mg/kg diet (60 min, 40-41 degrees C). Subsequently, Cu solubility with and without sodium phytate was measured. Adding Cu inhibited PP hydrolysis at pH 5.5 and pH 6.5 (P < 0.05). This inhibition was greater with higher concentrations of Cu. Tri-basic copper chloride and copper lysinate inhibited PP hydrolysis much less than copper sulfate pentahydrate, copper chloride, and copper citrate (P < 0.05). A strong negative relationship was observed between PP hydrolysis and soluble Cu at pH 5.5 (r = -0.76, P < 0.0001) and 6.5 (r = -0.54, P < 0.0001). In conclusion, pH, Cu concentration, and source influenced PP hydrolysis by phytase in vitro and were related to the amount of soluble Cu and the formation of insoluble copper-phytin complexes.  相似文献   
16.
No gold standard assay exhibiting error‐free classification of results has been identified for detection of Renibacterium salmoninarum, the causative agent of salmonid bacterial kidney disease. Validation of diagnostic assays for R. salmoninarum has been hindered by its unique characteristics and biology, and difficulties in locating suitable populations of reference test animals. Infection status of fish in test populations is often unknown, and it is commonly assumed that the assay yielding the most positive results has the highest diagnostic accuracy, without consideration of misclassification of results. In this research, quantification of R. salmoninarum in samples by bacteriological culture provided a standardized measure of viable bacteria to evaluate analytical performance characteristics (sensitivity, specificity and repeatability) of non‐culture assays in three matrices (phosphate‐buffered saline, ovarian fluid and kidney tissue). Non‐culture assays included polyclonal enzyme‐linked immunosorbent assay (ELISA), direct smear fluorescent antibody technique (FAT), membrane‐filtration FAT, nested polymerase chain reaction (nested PCR) and three real‐time quantitative PCR assays. Injection challenge of specific pathogen‐free Chinook salmon, Oncorhynchus tshawytscha (Walbaum), with R. salmoninarum was used to estimate diagnostic sensitivity and specificity. Results did not identify a single assay demonstrating the highest analytical and diagnostic performance characteristics, but revealed strengths and weaknesses of each test.  相似文献   
17.
The aim of this study was to determine which cells are the source of production and target for leukotriene (LTs) action within the bovine ovary. Luteal (CL, days 14–16 of the oestrous cycle), steroidogenic cells (LSC) and endothelial cells (LEC) of the bovine corpus luteum (CL), and granulosa cells (GC) were isolated enzymatically, cultured in a monolayer and incubated with LTC4, LTB4, Azelastine (an antagonist of LTC4) or Dapsone (an antagonist of LTB4). Then cells were collected for determination of mRNA expression for LT receptors (LTRs) and 5‐lipoxygenase (5‐LO) by real time RT‐PCR, and media were collected for determination of prostaglandin (PG)E2, F, progesterone (P4; LSC only), endothelin‐1 (ET‐1; LEC only) and 17‐β oestradiol (E2; GC only). The greatest mRNA expression for LTR‐II and 5‐LO were found in LEC, whereas LTR‐I mRNA expression did not differ among cell types. The level of PGE2 increased after LTs treatment in each type of ovarian cell, excluding LTC4 treatment in LEC. The secretion of PGF was also increased by LTs, but decreased after LTB4 treatment of LSC. In GC cultures, both LTs stimulated E2 secretion; in LEC cultures, LTB4 stimulated whereas LTC4 inhibited P4 secretion; in LEC cultures, LTC4 stimulated but LTB4 inhibited ET‐1 secretion. The results show that LTs are produced locally and are involved in PGs production/secretion in all examined cells (LSC, LEC and GC) of bovine ovary. Leukotriene treatment modulate secretion of E2, by GC, P4 by LSC and ET‐1 by LEC, which indicates that LTs are involved in regulation of ovarian secretory functions.  相似文献   
18.
Tydén, E., Bj?rnstr?m, H., Tjälve, H., Larsson, P. Expression and localization of BCRP, MRP1 and MRP2 in intestines, liver and kidney in horse. J. vet. Pharmacol. Therap. doi: 10.1111/j.1365‐2885.2009.01140.x. The gene and protein expression and the cellular localization of the ABC transport proteins breast cancer resistance protein (BCRP), multidrug resistance‐associated protein 1 (MRP1) and multidrug resistance‐associated protein 2 (MRP2) have been examined in the intestines, liver and kidney in horse. High gene and protein expression of BCRP and MRP2 were found in the small intestines, with cellular localization in the apical membranes of the enterocytes. In the liver, MRP2 was present in the bile canalicular membranes of the hepatocytes, whereas BCRP was localized in the cytoplasm of hepatocytes in the peripheral parts of the liver lobuli. In the kidney both BCRP and MRP2 were predominantly present in the distal tubuli and in the loops of Henle. In most tissues, the gene and protein expression of MRP1 were much lower than for BCRP and MRP2. Immunostaining of MRP1 was detectable only in the intestines and with localization in the cytoplasm of enterocytes in the caecum and colon and in the cells of serous acini of Brunner’s glands in the duodenum and the upper jejunum. The latter cells were also stained for BCRP, but not for MRP2. Many drugs used in horse are substrates for one or more of the ABC transport proteins. These transporters may therefore have important functions for oral bioavailability, distribution and excretion of substrate compounds in horse.  相似文献   
19.
Footing and gait of pigs on different concrete surfaces   总被引:1,自引:0,他引:1  
Because pigs frequently lose their footing and slip, it is important to understand slipping and its relation to different floor surfaces. An experiment was conducted to evaluate the gait and footing of young pigs walking on concrete floor surfaces having known friction characteristics and to determine critical skid resistance values in terms of the fitness of a concrete surface for flooring in pig quarters. Barrows were cinematographed with a high-speed 16-mm camera as they walked on various surfaces, and gait and footing were subsequently analyzed in motion studies. The six concrete floor test pads with different surface treatments (fine and coarse sand, fine and coarse broom, wood float and steel trowel) were evaluated for friction coefficient (skid resistance value) using a British pendulum tester both before and after pig tests. Leg angle, pastern angle and time variables were not related with average skid resistance value of the different floors. However, slip variables during a stride's stance phase per se were well related to surface-treatment differences in average skid resistance. Thus, the average skid resistance value generated by the British pendulum tester yielded one piece of objective information useful in assessing the fitness of concrete surfaces for floors in pig quarters. All the surfaces except the steel trowel surface had average skid resistance value of greater than 65 British pendulum number, and they all reduced a pig's chance of slipping relative to the steel trowel (less than 60 British pendulum number). The front leg was a more sensitive indicator than the rear of a floor's effect on the pig's gait and footing.  相似文献   
20.
Objective To examine the attitudes and opinions on veterinary education at the beginning and end of the veterinary course, and after graduation.
Design Longitudinal study.
Population Students – 154 in all – who began studying veterinary science at The University of Queensland in 1985 and 1986.
Procedure Questionnaires were completed in the first and fifth year of the course and in the second year after graduation. The data were analysed using the SAS System for Windows.
Results When they entered the course, the students were looking forward more to learning about animals than about basic sciences. At fifth year and after graduation most believed that more emphasis should have been placed on all facets of their education except the basic sciences. It may be difficult to increase this emphasis without placing undue pressure on the students, although more than half of the fifth year students and graduates agreed that there is much in the curriculum that is not needed by a practising veterinarian. Only one-third or less agreed that veterinarians are well equipped to practise veterinary science immediately they graduate. There was no relationship between the level of agreement with this statement, and the academic grades obtained.
Conclusions A majority of veterinary graduates do not believe that they are well equipped to practice immediately they graduate. They believe that more emphasis should have been placed on most facets of their education, but, conversely, that there is much in the curriculum that is not needed by a practising veterinarian.  相似文献   
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