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51.
1. Two experiments were performed with male, Ross broiler chicks to study the relationship between wheat specific weight and performance parameters and the effects of xylanase inclusion in diets of different wheat specific weight (SW). 2. In both studies wheat was incorporated at 667 g/kg and a protein concentrate based on soyameal 50, full fat soyameal, extrupro and herring meal and formulated to provide (g/kg) crude protein 370, crude oil 140, crude fibre 45, crude ash 110 was incorporated at 333 g/kg. 3. In Experiment 1, 3 wheats (69, 67, 57, SW respectively) without or with enzyme (Avizyme TX, Finnfeeds International) and in Experiment 2, 6 wheats (81, 77, 76, 70, 64, 61 SW respectively) were used and diets were fed ad libitum to individually caged birds. 4. In Experiment 1 the feeding period was 7 to 28 d and a total excreta collection was made from 14 to 20 d for determination of apparent metabolisable energy (AME) content. Experiment 2 started at 4 d with excreta collections from d 6 to 9, 10 to 12 and 13 to 19 inclusive for AME measurements. 5. In Experiment 1 there were no significant effects of wheat on dry matter (DM) intake but liveweight gain (LWG) and gain:food were significantly better for 67 SW than for 57 SW. Food enzyme inclusion improved LWG and gain:food but there was a significant wheat/enzyme interaction for gain:food with no improvement due to enzyme addition for 67 SW but a 5% improvement for 57 SW. There was no significant effect of wheat or enzyme addition on the measured AME contents of the diets. 6. In Experiment 2, although not statistically significant, there were large numerical differences in food intake between diets, with the lowest values occurring for 64 SW. For the complete period, wheat variety tended to affect LWG (P=0.057) with the best and worst results recorded for the 2 low SW wheats. Gain:food was significantly affected by wheat, the poorest values occurring with 64 SW and the best with 77 SW Diet AME content was also affected by wheat variety (P<0.01) but the low result obtained for 61 SW was not mirrored in the gain:food value. The lack of correlation between diet AME values and gain:food could not be attributed to differences in protein or amino acid content of the diets. 7. In Experiment 2 diet AME content increased from period 1.1 (6 to 9 d) to period 2 (13 to 20 d) by 7% but interpretation is hampered by the short adaptation period (2 d) prior to period 1.1. The AME values obtained in both studies during the 3rd week of age were towards the upper end of the range of values in the literature. 8. In Experiment 2 there was a good correlation (r2=0.95) between SW and wheat starch content and between SW and calculated wheat AME content (r2=0.40, P<0.001) but a poor correlation between SW and gain:food. There was also a high correlation between wheat AME content and starch content (r2=0.41, P<0.001). Taken together with the results of Experiment 1 it appeared that starch content is a better measure of wheat quality than specific weight. 相似文献
52.
The importance of seminal plasma on the fertility of subsequent artificial inseminations in swine 总被引:1,自引:0,他引:1
Rozeboom KJ Troedsson MH Hodson HH Shurson GC Crabo BG 《Journal of animal science》2000,78(2):443-448
Yorkshire x Landrace sows and gilts were used in a 3x2 factorial arrangement of treatments to determine the effect of uterine inflammation induced by either killed spermatozoa (KS) or bacterial lipopolysaccharide (LPS) on the fertility of a subsequent, optimally timed AI. Estrus was detected with a mature boar twice daily. Twelve hours after the first detection of estrus, females received intrauterine infusions of an inflammatory stimulus consisting of a 100-mL dose of extender containing 3x10(9) KS (n = 40), 20 microg of LPS (n = 40; positive control) or extender alone (n = 40; negative control). An insemination was performed 12 to 18 h later with 3x10(9) motile spermatozoa (i.e., fertile AI) suspended in either 100 mL of seminal plasma (SP; n = 60) or extender replenished with of estrogens (5 microg of estradiol-17beta, 4.5 microg of estrone sulfate, and 2 microg of estrone; n= 60). Transcutaneous ultrasound was performed at the time of fertile AI and again 24 h later to detect the presence or absence of preovulatory follicles. A fertile AI performed within 24 h before ovulation was considered optimal. Conception (CR) and farrowing rates (FR) were greater in females that received a fertile AI diluted with SP compared with extender (P<.01), and there was a significant (P<.05) treatment x fertile AI dilution medium interaction for both CR and FR. Females that received a fertile AI 12 h after infusion of extender had similar CR and FR regardless of fertile AI dilution medium. After inducing an inflammatory response with either KS or LPS, CR and FR were higher in females that received a fertile AI diluted with SP compared with fertile AI dilution with extender (P<.05). The effects of treatment and AI dilution media and their interactions were not significant for litter size in females that farrowed. These results show that the fertility of a subsequent AI can be impaired when semen is deposited into an inflamed environment created by an earlier AI, and this impairment was offset by inclusion of SP in the subsequent insemination. 相似文献
53.
Todd SE Mellor DJ Stafford KJ Gregory NG Bruce RA Ward RN 《Research in veterinary science》2000,68(2):125-134
The effects of food withdrawal for 30 hours and transport for up to 12 hours on 5- to 10-day-old calves were determined by monitoring plasma concentrations of glucose, beta-hydroxybutyrate, urea, lactate and creatine phosphokinase. In addition gamma-glutamyl transferase activity, packed cell volume, total plasma protein concentration, bodyweight and rectal temperature were recorded. Food withdrawal for 30 hours caused hypoglycemia but calves maintained normothermia and although their beta-hydroxybutyrate level increased indicating lipid mobilisation, the changes in blood urea level were minimal indicating low amino acid catabolism. When calves were transported for 12 hours in addition to having food withdrawn for 30 hours, they remained normoglycemic for six hours longer than non-transported calves, probably due to an effect of muscular activity during bracing against truck movements. Stocking calves at a lower density during transport apparently had a beneficial effect, as calves were able to lie down throughout the journey and therefore produced a similar metabolic profile to resting, non-transported animals. Transport and food withdrawal had no obvious effects on calf hydration. The results of this study suggest that food withdrawal for up to 30 hours and transport for up to 12 hours had no detrimental effects on the metabolism of healthy and clinically normal calves. With correct feeding regimes and transport protocols, welfare compromise in young, healthy calves being transported for up to 12 hours can be minimised when they are slaughtered within 30 hours of the start of transport. 相似文献
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Frequency of pulmonary mineralization and hypoxemia in 21 dogs with pituitary-dependent hyperadrenocorticism 总被引:1,自引:0,他引:1
Berry CR Hawkins EC Hurley KJ Monce K 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2000,14(2):151-156
The purpose of this study was to determine the frequency of hypoxemia and pulmonary mineralization using 99m Tc-methylene diphosphonate (99m Tc-MDP) in dogs with pituitary-dependent hyperadrenocorticism (PDH). Twenty-one dogs with PDH were pro-spectively evaluated using thoracic radiography, arterial blood gas analysis, and bone phase and pulmonary perfusion scintigraphy (using 99m Tc-macro-aggregated albumin [99m Tc-MAA]). The radiographs and bone and perfusion studies were evaluated subjectively. An averaged quantitative count density ratio was calculated between the thorax and cranial thoraco-lumbar vertebrae from lateral thoracic 99m Tc-MDP images. Thoracic: vertebral ratios were calculated using 99m Tc-MDP studies from 21 control dogs. The thoracic: vertebral ratios were compared between the 2 groups (PDH and control). The mean age (±SD) of the 21 PDH dogs was 10.2 (±3) years, whereas the mean age of the control group was 9.8 (±3) years. Seven of the 21 dogs with PDH were hypoxemic (denned as an arterial partial pressure of oxygen [PaO2 ] <80 mm Hg) with an average PaO2 (±SD) of 62 (±15) mm Hg. Of the 7 hypoxemic dogs, 2 were found to have pulmonary mineralization based on bone scintigraphic images. Pulmonary perfusion abnormalities were not identified using 99m Tc-MAA in any of the 21 PDH dogs. Six PDH dogs had an abnormal interstitial pulmonary pattern and 5 of these dogs were hypoxemic. The average quantitative thoracic: vertebral ratio was not significantly different between the PDH and control dogs (0.5 ± 0.4 versus 0.4 ± 0.1, P = .16). Causes of hypoxemia other than pulmonary thromboembolism should be considered in dogs with PDH. Pulmonary mineralization may contribute to hypoxemia in dogs with PDH. 相似文献
57.
Thyroid function and serum hepatic enzyme activity in dogs after phenobarbital administration 总被引:2,自引:0,他引:2
Gieger TL Hosgood G Taboada J Wolfsheimer KJ Mueller PB 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2000,14(3):277-281
Phenobarbital is the drug of choice for control of canine epilepsy. Phenobarbital induces hepatic enzyme activity, can be hepatotoxic, and decreases serum thyroxine (T4) concentrations in some dogs. The duration of liver enzyme induction and T4 concentration decreases after discontinuation of phenobarbital is unknown. The purpose of this study was to characterize the changes in serum total T4 (TT4), free T4 (FT4), thyroid-stimulating hormone (TSH), cholesterol and albumin concentrations, and activities in serum of alanine aminotransferase (ALT), alkaline phosphatase (ALP), and gamma-glutamyl transferase (GGT) after discontinuation of long-term phenobarbital administration in normal dogs. Twelve normal dogs were administered phenobarbital at a dosage of approximately 4.4-6.6 mg/kg PO q12h for 27 weeks. Blood was collected for analysis before and after 27 weeks of phenobarbital administration and then weekly for 10 weeks after discontinuation of the drug. The dogs were clinically normal throughout the study period. Serum ALT and ALP activity and TSH and cholesterol concentrations were significantly higher than baseline at week 27. Serum T4 and FT4 were significantly lower. Serum albumin and GGT were not changed from baseline at week 27. Changes in estimate of thyroid function (TT4, FT4, TSH) persisted for 1-4 weeks after discontinuation of phenobarbital, whereas changes in hepatic enzyme activity (ALT, ALP) and cholesterol concentration resolved in 3-5 weeks. To avoid false positive results, it is recommended that thyroid testing be performed at least 4 weeks after discontinuation of phenobarbital administration. Elevated serum activity of hepatic enzymes 6-8 weeks after discontinuation of phenobarbital may indicate hepatic disease. 相似文献
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Vulnerability of xylem to loss of hydraulic conductivity caused by drought-induced cavitation was determined for three riparian cottonwood species in Lethbridge, Alberta: Populus deltoides Bartr., P. balsamifera L., and P. angustifolia James. These species suffered 50% loss of hydraulic conductivity in one-year-old stem segments when xylem pressure potential fell to -0.7 MPa for P. deltoides and -1.7 MPa for P. balsamifera and P. angustifolia, making them the three most vulnerable tree species reported so far in North America. The possible contribution of drought-induced xylem dysfunction to the decline of riparian ecosystems in dammed rivers is discussed. 相似文献
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