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191.
The effects of two non‐steroidal anti‐inflammatory drugs on the mobility of laying hens with keel bone fractures 下载免费PDF全文
Mohammed AF Nasr Christine J Nicol Lindsay Wilkins Joanna C Murrell 《Veterinary anaesthesia and analgesia》2015,42(2):197-204
ObjectiveInvestigate the effects of administration of meloxicam and carprofen on the mobility of hens with and without keel fractures.Study designWithin each of two experiments a ‘blinded’ randomised cross over design whereby birds received either the test drug (carprofen or meloxicam) or saline.AnimalsTwo groups of Lohman Brown hens with and without keel bone fractures.MethodsThe first group (n = 63) was treated with carprofen 25 mg kg−1 and saline subcutaneously, twice. The second group (n = 40) was treated with meloxicam (5 mg kg−1) and saline subcutaneously. The latency of birds to fly down from perches 50, 100 and 150 cm above the ground was measured after each treatment. Data from experiment 1 and 2 were analysed separately; the effects of drug treatment compared with saline on landing time for birds with and without keel bone fractures were evaluated using MLwiN.ResultsIn both experiments latency to fly down from perches was longer in hens with keel fractures and there was a significant interaction between perch height and fracture status. For carprofen, at the 50 cm, 100 cm and 150 cm perch heights, birds with fractures took (mean ± SD) 2.5 ± 2.9, 6.8 ± 9.7 and 11.5 ± 13.2 seconds respectively to fly down compared with 1.3 ± 0.5, 2.3 ± 1.2 and 4.2 ± 3.1 seconds for birds without fractures. For meloxicam, at the 50 cm, 100 cm and 150 cm perch heights, birds with fractures took 2.9 ± 2.5, 49.8 ± 85.4 and 100.3 ± 123.6 seconds respectively compared with 0.7 ± 0.5, 2.5 ± 7.1 and 3.0 ± 4.6 seconds to fly down for birds without fractures. There was no significant effect of carprofen or meloxicam treatment.Conclusion and clinical relevanceThese data provide further confirmation that keel fractures reduce the willingness of birds to move from perches. 相似文献
192.
D W Bohnert B T Larson S J Lewis C J Richards K C Swanson D L Harmon G E Mitchell 《Journal of animal science》1999,77(9):2545-2553
Eight multicatheterized wethers (35.9 +/- .8 kg BW) were used in a replicated 4 x 4 Latin square design to measure N retention and net uptake and release of plasma metabolites across the portal-drained viscera (PDV), hepatic (HEP), and total splanchnic (TS) tissues in response to changes in supplemental N source. Treatments selected to provide different amounts of undegradable intake protein (UIP) were urea, soybean meal (SBM), poultry by-product meal (PBM), and bloodmeal:corn gluten meal (BMCGM; 50:50 CP basis). Diets (urea, SBM, PBM, and BMCGM) contained 12.9, 13.8, 13.6, and 13.2% CP, respectively. Periods were 10 d, with total feces and urine collected on d 7 to 10 and blood sampled on d 10. Wethers were fed at 2% of BW in 12 daily portions. Nitrogen retention was 2.2, 3.3, 4.1, and 4.4 g/d for urea, SBM, PBM, and BMCGM, respectively. Urea had less (P < .01) N retention than SBM, PBM, and BMCGM; SBM had less N retention (P < .01) than PBM and BMCGM. Arterial, portal, and hepatic plasma flows were greater (P < .09) for SBM than for PBM and BMCGM (21 vs 16, 17; 84 vs 72, 72; 105 vs 87, 88 L/h). Portal plasma flow was greater (P < .10) for urea than for SBM, PBM, and BMCGM (85 vs 84, 72, 72 L/h). Portal-drained viscera and TS alpha-amino N (AAN) fluxes were less (P < .05) for PBM than for BMCGM (20.5 vs 26.6 and 7.2 vs 15.1 mmol/h), but TS AAN flux was less (P < .05) for urea than for SBM, PBM, and BMCGM (6.9 vs 16.9, 7.2, 15.1 mmol/h). Portal-drained viscera flux and HEP removal of NH3 N were greater (P < .001) for SBM than for PBM and BMCGM (27.7 vs 19.4, 20.6; -28.1 vs -20.0, -21.4 mmol/h). Gut use was less (P = .07) and HEP and TS fluxes of urea N were greater (P < .01) for SBM than for PBM and BMCGM (-4.92 vs -8.32, -7.93; 25.87 vs 16.54, 20.00; 20.95 vs 8.22, 12.07 mmol/h). These data suggest that PBM and BMCGM improved efficiency of N use compared with urea and SBM by reducing urinary N loss. 相似文献
193.
194.
Six Suffolk wether lambs (40.9+/-1.05 kg) surgically fitted with ruminal and double-L-shaped duodenal and ileal cannulas were used in a 3 x 6 Latin rectangle design to investigate the effects of three corn hybrids on site and extent of disappearance of nutrients and rumen characteristics. Treatments were 1) a conventional yellow dent corn (CC) diet, 2) a NutriDense corn (NC) diet, and 3) a waxy corn (WC) diet. Diets consisted of 43.9% cracked corn grain, 39.1% cottonseed hulls, 15.3% soybean meal, 1.49% vitamin and mineral supplement, and 0.21% chromic oxide (DM basis). Lambs were fed twice daily at 1.8 x NEm requirement. Ruminal pH, fluid dilution rate, volume, NH3 N, and total VFA concentrations, as well as molar proportions of isobutyrate, butyrate, and valerate, were similar (P > 0.10) among dietary treatments. Apparent and true OM disappearances (g/d and percentage of OM intake) from the stomach were similar (P > 0.10) among dietary treatments. Apparent OM disappearance (percentage of duodenal OM flow) from the small intestine was higher (P < 0.05) for the WC than for the NC treatment. Apparent total tract OM disappearance (percentage of OM intake) was also similar (P > 0.10) among dietary treatments. Total apparent and true starch disappearances (g/d) from the stomach were higher (P < 0.05) for the WC diet than for the CC and NC diets. However, apparent and true starch disappearances from stomach as percentage of starch intake were higher (P < 0.05) for the WC diet than for the CC diet. Starch disappearance (g/d) from the small intestine was higher (P < 0.05) for the CC diet than for the WC diet; however, apparent starch disappearance (percentages of duodenal starch flow) from the small intestine was higher (P < 0.05) for the WC diet than for the CC diet. Duodenal flows of total N, bacterial N, NH3 N, and non-NH3 nonbacterial N (g/d) and efficiencies of bacterial protein production (g of bacterial N/kg of true or apparent OM disappearing in the stomach) were similar (P > 0.10) among dietary treatments. Apparent and true N disappearance from stomach (g/d) and apparent total tract N disappearance (percentage of N intake) were also similar (P > 0.10) among dietary treatments. Total N disappearance from the hindgut was -0.81, -1.06, and -1.46 g/d for CC, NC, and WC, respectively, and was different (P < 0.05) between CC and WC diets. Results indicated that higher ruminal starch disappearance in WC did not increase microbial N production or efficiency when compared to CC. 相似文献
195.
van de Ligt JL Lindemann MD Harmon RJ Monegue HJ Cromwell GL 《Journal of animal science》2002,80(2):449-455
A total of 60 pigs from 15 litters were used during two experiments to assess the effects of maternal supplementation of Cr tripicolinate on performance and immune status of the offspring during the first 42 d after weaning. Gilts were raised on diets with either 0 (-Cr) or 200 (+Cr) ppb supplemental Cr from Cr tripicolinate. Their offspring were weaned at about 23 d of age. Pigs from dams fed supplemental Cr were fed Cr-supplemented diets after weaning and pigs from unsupplemented dams were not fed supplemental Cr. Pigs were housed in groups of three according to litter origin (six -Cr and nine +Cr) and BW. Feed and water were available for ad libitum consumption. Serum was collected 24 h after birth, the day after weaning (d 0), and, subsequently, every 7 d through d 28 for measurement of total immunoglobulin (Ig) G and IgM. For the 42-d nursery period, ADG (511 and 531 g/d for -Cr and +Cr, respectively), ADFI (827 and 851 g/d), and gain:feed (0.62 and 0.62) were not affected (P > 0.15) by Cr. Total IgG was not affected (P > 0.10) by Cr on d 0 (7.6 and 7.7 mg/mL for -Cr and +Cr, respectively) or on d 7 (6.3 and 6.1 mg/mL for -Cr and +Cr, respectively), when the lowest concentrations were observed. By d 28, total IgG had risen (11.7 and 8.9 mg/mL for -Cr and +Cr, respectively) and was affected by Cr (P = 0.03). Total IgM followed a similar pattern and was lowest on d 7. In each trial, IgG at 24 h after birth was inversely related to IgG from d 14 through 28 in the nursery. Additionally, the lowest Ig concentrations occurred between 4 and 5 wk of age, rather than at weaning (23 d of age); this may represent a vulnerable period for weanling pigs. Supplementation of the weanling pig diets with Cr tripicolinate did not significantly affect performance and immune status during the postweaning period. 相似文献
196.
Fat source and calcium level effects on finishing steer performance, digestion, and metabolism 总被引:3,自引:0,他引:3
A 111-d finishing study evaluated animal growth and carcass characteristics using 138 steers (366 kg) in a randomized complete block design with a 2 x 3 factorial arrangement of treatments. The dietary treatments consisted of no supplemental fat or 3.5% tallow or soybean oil soapstock (SS) fed with .6% and .9% dietary Ca. Fat increased DMI (P less than .05) but interacted with Ca level (P less than .05) for gain/feed and ADG. All diets containing fat or .9% Ca were converted more efficiently to gain than the .6% Ca, no supplemental fat diet (P less than .05). The .9% Ca interacted with fat source to decrease gain (P less than .05) and tended to decrease efficiency in the tallow diet but improved efficiency (P less than .05) and tended to improve gain in the no-fat diet. In the SS diet, .9% Ca had no effect on ADG, DMI, or efficiency of gain. Fat addition increased backfat (P less than .10) and interacted with Ca on hot carcass weight, final weight, and dressing percentage (P less than .05). Feeding fat increased the proportion of 18:0 (P less than .02) and decreased the proportion of 16:1 fatty acids (P less than .06) in intermuscular fat. A replicated 3 x 3 Latin square design, using six Holstein steers (349 kg) fed three diets, with no supplemental fat or 3.5% SS or tallow with 1.0% Ca, was used to explore the effects of fat sources when fed with high Ca on digestion and metabolism. Ruminal fluid pH was higher (P less than .10) when steers were fed fat. Adding fat did not affect (P greater than .10) duodenal or ileal pH, VFA proportions or total concentration, or ruminal liquid volume or flow rate. Liquid retention time was shorter and liquid rate of passage was higher (P less than .05) with dietary fat addition. Adding fat did not affect site or extent of starch or DM digestion. There was net synthesis of 16:0, 18:0, and 18:1 fatty acids in the rumen. When steers were fed tallow, synthesis of 16:0 and 18:0 fatty acids in the rumen was lower (P less than .10) than when steers were fed SS. Feeding fat tended to decrease (P = .11) bacterial N flowing at the duodenum but did not affect nonbacterial N or total N. Fat addition seems to affect ruminal kinetics, and the effects may vary with fat source, particularly relative to fatty acid synthesis and digestion. 相似文献
197.
Sullivan SA Harmon BG Purinton PT Greene CE Glerum LE 《Journal of the American Veterinary Medical Association》2003,223(12):1783-7, 1778
A 9-month-old male Miniature Schnauzer was examined because of a lifelong history of behavioral abnormalities, including hypodipsia. Diagnostic evaluation revealed marked hypernatremia and a single forebrain ventricle. The behavioral abnormalities did not resolve with correction of the hypernatremia, and the dog was euthanatized. At necropsy, midline forebrain structures were absent or reduced in size, and normally paired forebrain structures were incompletely separated. Findings were diagnostic for holoprosencephaly, a potentially genetic disorder and the likely cause of the hypodipsia. Similar evaluation of affected Miniature Schnauzer dogs may reveal whether holoprosencephaly routinely underlies the thirst deficiency that may be seen in dogs of this breed. 相似文献
198.
OBJECTIVE: To characterize the vascular anatomy of the third compartment of the stomach of llamas. ANIMALS: 7 adult llamas. PROCEDURE: Immediately after each llama was euthanatized, vascular replicas of tissue from the third compartment were prepared by use of methylmethacrylate monomer and catalyst. Following chemical removal of tissue, the casts were further prepared for examination via scanning electron microscopy. By use of barium solution, microangiography was also performed on fixed tissue samples; the infused tissue was sectioned and imaged radiographically. Tissue samples were also collected for histologic evaluation after fixation and H&E staining. RESULTS: The third compartment was supplied by 4 pairs of primary arteries and veins located around the circumference of the structure. From these vessels, smaller arteries and veins branched to supply the serosal surface and penetrated deeper through the tunica muscularis to supply the submucosal and mucosal layers. An extensive capillary network was arranged in a hexagonal array surrounding the gastric glands, such that the mucosal aspect of the replicas had a honeycomb-like appearance. Histologically, variably sized villous projections lined by a single layer of epithelial cells with an extensive glandular network were observed. CONCLUSIONS AND CLINICAL RELEVANCE: The third compartment of the stomach of llamas is a highly vascular structure with an extensive anastomotic capillary network at the luminal surface. Branching vessels provide extensive collateral circulation, and it appears that surgical incisions should heal well. Incisions in the third compartment should be oriented parallel to the longitudinal plane. 相似文献
199.
200.
Tricarico JM Abney MD Galyean ML Rivera JD Hanson KC McLeod KR Harmon DL 《Journal of animal science》2007,85(3):802-811
Three experiments were conducted to examine the effects of an Aspergillus oryzae extract containing alpha-amylase activity on performance and carcass characteristics of finishing beef cattle. In Exp. 1, 120 crossbred steers were used in a randomized complete block design to evaluate the effects of roughage source (alfalfa hay vs. cottonseed hulls) and supplemental alpha-amylase at 950 dextrinizing units (DU)/kg of DM. Significant roughage source x alpha-amylase interactions (P < 0.05) were observed for performance. In steers fed cottonseed hulls, supplemental alpha-amylase increased ADG through d 28 and 112 and tended (P < 0.15) to increase ADG in all other periods. The increases in ADG were related to increased DMI and efficiency of gain during the initial 28-d period but were primarily related to increased DMI as the feeding period progressed. Supplemental alpha-amylase increased (P = 0.02) the LM area across both roughage sources. In Exp. 2, 96 crossbred heifers were used in a randomized complete block design with a 2 x 3 factorial arrangement of treatments to evaluate the effects of corn processing (dry cracked vs. high moisture) and supplemental alpha-amylase concentration (0, 580, or 1,160 DU/kg of DM). Alpha-amylase supplementation increased DMI (P = 0.05) and ADG (P = 0.03) during the initial 28 d on feed and carcass-adjusted ADG (P = 0.04) across corn processing methods. Longissimus muscle area was greatest (quadratic effect, P = 0.04), and yield grade was least (quadratic effect, P = 0.02) in heifers fed 580 DU of alpha-amylase/kg of DM across corn processing methods. In Exp. 3, 56 crossbred steers were used in a randomized complete block design to evaluate the effects of supplemental alpha-amylase (930 DU/kg of DM) on performance when DMI was restricted to yield a programmed ADG. Alpha-amylase supplementation did not affect performance when DMI was restricted. We conclude that dietary alpha-amylase supplementation of finishing beef diets may result in increased ADG through increased DMI under certain dietary conditions and that further research is warranted to explain its mode of action and interactions with dietary ingredients. 相似文献