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121.
The behaviour of two pens of mixed British breed male sheep transported by ship from New Zealand to Saudi Arabia was studied. One of the groups was carried above decks (n = 128) and one below decks (n = 116). Observations were conducted four to five times daily throughout the 24-day voyage. Over the whole voyage the most common activities were standing, lying and feeding. Overall, the animals adapted reasonably well to the shipboard environment, with most gaining weight. The mortality rate in the study pens averaged 2.5%, which was similar to that of the total shipment and average for this type of voyage. The behavioural measures appeared to provide sensitive indices of changes in the welfare of the sheep. An increase in lying activity, panting and drinking and a decrease in feeding during the latter part of the voyage were indicative of increasing heat stress. Plunging at the feed and water troughs led to loss of footing and increased the likelihood of smothering. This activity occurred after periods without feed or without water. Plunging also occurred when sheep moved towards the ventilators. Other factors associated with reduced well-being were the high stocking density which, combined with a wet faecal pad, limited movement towards feed or water and increased the likelihood of smothering. 相似文献
122.
Matthews R 《Science (New York, N.Y.)》1992,255(5049):1204-1205
123.
This experiment investigated the effect of dietary supplementation with essential oils from Artemisia afra and Moringa oleifera on haemato‐immunological parameters and resistance in Clarias gariepinus (African Sharptooth catfish) (Burchell, 1822) challenged with Aeromonas hydrophila. The experiment lasted for 45 days. Prior to and postchallenge, white blood cells significantly increased (p < .05) from the 3% to 12% M. oleifera and A. afra supplementation. Pre‐challenge, no significant differences (p > .05) in red blood cells, haemoglobin and haematocrit were observed between the control and M. oleifera supplementation, while in the A. afra supplementation, RBC and HCT significantly increased from the 6% to 12%. Postchallenge, RBC, HGB and HCT were significantly lower (p < .05) in the control and the 3% and 6% M. oleifera and A. afra supplementation. Both pre‐ and postchallenge, nitro‐blue tetrazolium levels significantly increased (p < .05) from the 3% to 12% M. oleifera supplementation while no significant differences (p > .05) were observed in lysozyme activity between the control and treatment groups. In A. afra, NBT and lysozyme activities increased significantly (p < .05) from the 6% to 12% supplementation pre‐ and postchallenge. Survival rate increased from the 3% to 12% in M. oleifera and A. afra supplementation groups. Significant kidney histological alterations were noted in the control and the 3% and 6% supplementation of both plants postchallenge, while no major histological changes were observed between treatment groups and the control pre‐challenge. The results demonstrate that EO from M. oleifera and A. afra can improve immunity and enhance survival in C. gariepinus. 相似文献
124.
Kavalier AR Litt A Ma C Pitra NJ Coles MC Kennelly EJ Matthews PD 《Journal of agricultural and food chemistry》2011,59(9):4783-4793
Hop (Humulus lupulus L.) inflorescences, commonly known as "hop cones", are prized for their terpenophenolic contents, used in beer production and, more recently, in biomedical applications. In this study we investigated morphological and phytochemical characteristics of hop cones over five developmental stages, using liquid chromatography coupled to time-of-flight mass spectrometry (LC-TOF-MS), and ultrahigh performance liquid chromatography photodiode array detection (UHPLC-PDA) methods to quantitate 21 polyphenolics and seven terpenophenolics. Additionally, we used light microscopy to correlate phytochemical quantities with changes in the morphology of the cones. Significant increases in terpenophenolics, concomitant with glandular trichome development and associated gross morphological changes, were mapped over development to fluctuations in contents of polyphenolic constituents and their metabolic precursor compounds. The methods reported here can be used for targeted metabolic profiling of flavonoids, phenolic acids, and terpenophenolics in hops, and are applicable to quantitation in other crops. 相似文献
125.
Michael Walker DVM Sandee Hartsfield DVM MS Nora Matthews DVM George White DVM Margaret Slater DVM PhD Jane Thoos C.T. Tech 《Veterinary radiology & ultrasound》1993,34(2):93-98
Increasingly severe degrees of pneumothorax were produced in 6 adult anesthetized bloodhounds. Computed tomography (CT) of the thorax was performed on each dog to evaluate the effects of pneumo thorax on thoracic and on pulmonary cross-sectional area (TA and PA). Arterial PO2 (PaO2 ) and PCO2 (PaCO2 ), heart rate (HR), and mean arterial blood pressure (MAP) were determined and related to the severity of pneumothorax. Volumes of air equal to 1, 1.5 and 2 times functional residual capacity of the lung produced approximately 33%, 40%, and 50% reductions in pulmonary area respectively. These amounts of atelectasis correspond to a radiographically "moderate" degree of pneumothorax. As severity of pneumothorax increased, thoracic area consistently increased, PaO2 consistently decreased, and PaCO2 consistently increased, with all being statistically significant relationships (p<0.0001); but HR and MAP were variable and showed no statistical correlation to the degree of pneumothorax (p>0.2). 相似文献
126.
The hypothesis is set forth that schizodeme (kDNA) typing of Trypanosoma cruzi, and possible other parasites, may be used to resolve the problem associated with the protean clinical manifestations of the disease. kDNA typing of T. cruzi clones may turn out to be useful in: (1) diagnosis; (2) prognosis; (3) production of species (generic) vaccines; (4) the study of autoimmunity. We recommend that an international culture bank of schizodeme-type T. cruzi be established. 相似文献
127.
Four experiments were conducted to determine whether betaine (BET) could replace dietary methionine (MET) in diets for weanling pigs. Pigs in each experiment were allotted to treatments on the basis of weight in a randomized complete block design. Each treatment was replicated four (Exp. 4), five (Exp. 1 and 2), or six (Exp. 3) times with five or six pigs per replicate. In Exp. 1, pigs were fed a diet formulated to be deficient in total sulfur amino acids (TSAA) (negative control; NC) or the NC + 0.05 or 0.10% MET or BET during Phase 1 and 0.035 or 0.07% MET or BET during Phase 2. Growth performance was not affected (P > 0.10) by dietary treatments, indicating that the diets were not deficient in TSAA. In Exp. 2, graded levels of TSAA (0.74, 0.79, 0.84, 0.89, or 0.94%) were fed. Overall ADG was increased (0 vs added MET, P < 0.07) in pigs fed TSAA levels of 0.79% or greater, but gain:feed was not affected (P > 0.10) by diet. Overall ADFI was increased (linear, P < 0.08) and plasma urea N (PUN) was decreased (quadratic, P < 0.01) as the level of TSAA was increased. Most of the change in ADG, PUN, and ADFI occurred between 0.74 and 0.84% TSAA. Thus, the 0.74% TSAA diet was used in Exp. 3 as the NC. In Exp. 3, the diets included the following: 1) NC, 2) NC + 0.05% MET, 3) NC + 0.10% MET, 4) NC + 0.039% BET, or 5) NC + 0.078% BET. The addition of MET resulted in increased (linear, P < 0.10) ADG, ADFI, and gain:feed, but MET decreased PUN (linear, P < 0.05). Daily gain, ADFI, and TSAA intake were not different (P > 0.10) between pigs fed 0.05% MET or 0.039% BET, but gain:feed was decreased (P < 0.01) in pigs fed 0.039% BET compared with pigs fed 0.05% MET. In Exp. 4, a 2 x 2 x 2 factorial arrangement of treatments was used (MET, 0 or 0.072%; cystine, 0 or 0.059%; or BET, 0 or 0.057%). Overall ADG and gain:feed were increased (P < 0.10) in pigs fed MET. The intake of TSAA was increased (P < 0.05), and PUN was decreased (P < 0.10) in pigs fed MET or cystine. Overall ADFI was increased in pigs fed BET or MET independently but not affected when BET and MET were fed together (BET x MET, P < 0.10). The addition of BET to TSAA-deficient diets resulted in increased ADG, which was due to an increase in ADFI (TSAA intake). Thus, BET did not spare MET in this experiment. 相似文献
128.
129.
130.
Graham A. Matthews 《Pest management science》1977,8(1):96-100
If transfer of pesticide from the spray nozzle to the target is to be more efficient, a clearer definition is required of the sites which droplets should reach. Such biological targets are examined on both macro and micro scales in this paper. 相似文献