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71.
Crews C Hough P Godward J Brereton P Lees M Guiet S Winkelmann W 《Journal of agricultural and food chemistry》2006,54(17):6261-6265
This paper describes the composition of 30 grape-seed oils obtained from France, Italy, and Spain during 2002-2003. Oils were extracted from the seeds using small-scale industrial solvent extraction equipment and analyzed in their unrefined state using standard methods for fatty acids, fatty acids in the triacylglycerol 2-position, tocopherols and tocotrienols, triglycerides, sterols, steradienes, and iodine value. Values for the composition of the sterols, triglycerides, fatty acids, iodine value, and tocopherol composition were generally in good agreement with the results of previous similar surveys. Steradienes (stigmastadiene, campestadiene, stigmastatriene, and campestatriene) were detected in the oil and were probably formed from sterols during the extraction process. 相似文献
72.
At high pressure the alkali metals potassium, rubidium, and cesium transform to metals that have a d1 electron configuration, becoming transition metal-like. As a result, compounds were shown to form between potassium and the transition metal nickel. These results demonstrate that the chemical behavior of the alkali metals under pressure is very different from that under ambient conditions, where alkali metals and transition metals do not react because of large differences in size and electronic structure. They also have significant implications for the hypothesis that potassium is incorporated into Earth's core. 相似文献
73.
Crews C Hough P Godward J Brereton P Lees M Guiet S Winkelmann W 《Journal of agricultural and food chemistry》2005,53(12):4853-4860
This paper describes the composition of walnut oils obtained from nuts collected from seven countries that are major suppliers of walnut oil. Oils were extracted from the nuts using small-scale industry pressing equipment and analyzed using standard methods for fatty acids, fatty acids in the triacylglycerol 2-position, tocopherols and tocotrienols, triacylglycerols, sterols, steradienes, and iodine value. Values for the composition of the sterols, triacylglycerols, fatty acids, iodine value, and tocopherol composition were generally in good agreement with the results of previous similar surveys. Tocotrienols were not detected in any sample. Steradienes (stigmastadiene, campestadiene, stigmastatriene, and campestatriene) were not detected in any oil. 相似文献
74.
75.
Objective To monitor changes in hoof morphology in response to barefoot trimming. Methods Seven horses were trimmed every 6 weeks according to barefoot trimming principles, which involved levelling the hoof to live sole, lowering the heels, bevelling the toe and rounding the peripheral wall, while leaving the sole, frog and bars intact. A 4‐month period was allowed to lower the heels sufficiently to achieve a hoof shape representative of the barefoot trim. This was regarded as the starting point for morphological adaptations in response to maintenance of the trim. Hoof morphology was measured from lateral, dorsal and solar view photographs and lateromedial radiographs taken at 0, 4 and 16 months. Changes from 0 to 4 months represented differences between a natural hoof shape and the trim, while changes from 4 to 16 months represented adaptive effects during hoof growth. Results Establishment of the barefoot trim involved significant shortening of the toe, heel and medial and lateral walls, with increases in angulation at the toe, medial and lateral walls, but not at the heel. Maintenance of the trim resulted in a palmar/plantar migration of the heels, with increases in support length, heel angle and solar angle of the distal phalanx (P3). Conclusions Bevelling the toe and engaging the frog and bars in the weight‐bearing function of the foot resulted in elevation of the heel angle and solar angle of P3. These changes may be beneficial in treating under‐run heels and negative solar plane angulation of P3. 相似文献
76.
Crowley JJ Evans RD Mc Hugh N Kenny DA McGee M Crews DH Berry DP 《Journal of animal science》2011,89(11):3372-3381
Most studies on feed efficiency in beef cattle have focused on performance in young animals despite the contribution of the cow herd to overall profitability of beef production systems. The objective of this study was to quantify, using a large data set, the genetic covariances between feed efficiency in growing animals measured in a performance-test station, and beef cow performance including fertility, survival, calving traits, BW, maternal weaning weight, cow price, and cull cow carcass characteristics in commercial herds. Feed efficiency data were available on 2,605 purebred bulls from 1 test station. Records on cow performance were available on up to 94,936 crossbred beef cows. Genetic covariances were estimated using animal and animal-dam linear mixed models. Results showed that selection for feed efficiency, defined as feed conversion ratio (FCR) or residual BW gain (RG), improved maternal weaning weight as evidenced by the respective genetic correlations of -0.61 and 0.57. Despite residual feed intake (RFI) being phenotypically independent of BW, a negative genetic correlation existed between RFI and cow BW (-0.23; although the SE of 0.31 was large). None of the feed efficiency traits were correlated with fertility, calving difficulty, or perinatal mortality. However, genetic correlations estimated between age at first calving and FCR (-0.55 ± 0.14), Kleiber ratio (0.33 ± 0.15), RFI (-0.29 ± 0.14), residual BW gain (0.36 ± 0.15), and relative growth rate (0.37 ± 0.15) all suggest that selection for improved efficiency may delay the age at first calving, and we speculate, using information from other studies, that this may be due to a delay in the onset of puberty. Results from this study, based on the estimated genetic correlations, suggest that selection for improved feed efficiency will have no deleterious effect on cow performance traits with the exception of delaying the age at first calving. 相似文献
77.
LJ Smith L Krugner-Higby M Clark D Ney E Dahly 《Veterinary anaesthesia and analgesia》2003,30(2):116-117
A delayed‐release formulation of liposome‐encapsulated oxymorphone was produced using a novel dehydration–rehydration technique. The purpose of this study was to (i) compare the analgesic properties of this preparation with those of repeated injections of standard oxymorphone in rats with post‐operative visceral pain and (ii) determine whether liposome‐encapsulated oxymorphone differed from standard oxymorphone in duration of the effect. Visceral pain was elicited in approximately 300 g Sprague–Dawley rats by intestinal resection performed under isoflurane anesthesia. Rats were monitored with pulse oximetry; mean anesthesia time (35 ± 10 minutes) did not differ between the groups. Rats were randomly divided into two groups: Group 1 received 1.2 mg kg?1 liposome‐encapsulated oxymorphone SC once at skin closure and 0.2 mL of saline SC every 4 hours; Group 2 received 0.2 mL liposome‐encapsulated sucrose SC once at skin closure and 0.3 mg kg?1 standard oxymorphone SC every 4 hours. In both groups, a behavioral ethogram for pain score (grooming, porphyrin staining, body position) was recorded every 4 hours for 48 hours after surgery. Observers were blinded to the treatment. Body weight, food consumption, and urine output were recorded daily for 7 days after anesthetic recovery. Data were analyzed using anova , with significance at p < 0.05. Based on the behavioral pain score, a single injection of liposome‐encapsulated oxymorphone was as effective for relief of post‐surgical visceral pain in rats as multiple (every 4 hours) injections of standard oxymorphone administered over a 48 hour period (p = 0.18). In rats, given one dose of liposome‐encapsulated oxymorphone, the mean body weight change from day 0 to day 7 was +9.4 g, whereas rats given multiple injections of standard oxymorphone had a mean body weight change of ?3.6 g over this time (p < 0.01). Mean daily food consumption was significantly less in rats given multiple injections of standard oxymorphone (p < 0.05). There was no difference between groups in urine production. In conclusion, a single dose of liposome‐encapsulated oxymorphone was effective in treating visceral pain in rats. Rats treated with liposome‐encapsulated oxymorphone had improved recovery, based on body weight changes and food consumption, compared with rats treated with multiple doses of standard oxymorphone. Liposome‐encapsulated oxymorphone offered advantages including provision of effective analgesia, prolonged dosing intervals, and minimal handling stress. 相似文献
78.
S.M. Simmerson P.J. Armstrong A. Wünschmann C.R. Jessen L.J. Crews R.J. Washabau 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2014,28(2):331-337
Background
A poorly understood protein‐losing enteropathy (PLE) disorder has been reported in Yorkshire Terrier dogs.Objectives
To describe clinical features, intestinal histopathology, and outcome in Yorkshire Terrier dogs with PLE, and to identify variables predictive of outcome.Animals
Thirty client‐owned Yorkshire Terrier dogs with PLE.Methods
Retrospective study. Records of dogs with a diagnosis of PLE were reviewed. Intestinal histopathology was interpreted using the World Small Animal Veterinary Association gastrointestinal histopathology classification system. Discriminate analysis techniques were used to identify variables predictive of outcome.Results
Females outnumbered males (20/30). Median age was 7 years (range 1–12). Common clinical signs were diarrhea (20/30), vomiting (11), ascites and abdominal distension (11), and respiratory difficulty (8). Histopathologic abnormalities included villous lymphatic dilatation, crypt lesions, villous stunting, and variable increases in cellularity of the lamina propria. All dogs were treated with glucocorticoids. Of 23 dogs with long‐term follow‐up, 9 had complete, and 3 had partial, resolution of signs, and 11 failed to respond to treatment. Median survival of responders was 44 months and of nonresponders was 12 months, with 4 dogs experiencing peracute death. Vomiting, monocytosis, severity of hypoalbuminemia, low blood urea nitrogen concentration, and villous blunting were predictive of survival <4 months.Conclusions
In addition to classic GI signs, Yorkshire Terriers with PLE often show clinical signs associated with hypoalbuminemia and low oncotic pressure. Lymphatic dilatation, crypt lesions, and villous stunting are consistent histopathologic findings. Clinical outcomes are variable, but many dogs experience remission of clinical signs and prolonged survival. 相似文献79.
I.D.P.S. Diaz D.H. Crews Jr R.M. Enns 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2014,131(3):217-226
A data set based on 50 studies including feed intake and utilization traits was used to perform a meta‐analysis to obtain pooled estimates using the variance between studies of genetic parameters for average daily gain (ADG); residual feed intake (RFI); metabolic body weight (MBW); feed conversion ratio (FCR); and daily dry matter intake (DMI) in beef cattle. The total data set included 128 heritability and 122 genetic correlation estimates published in the literature from 1961 to 2012. The meta‐analysis was performed using a random effects model where the restricted maximum likelihood estimator was used to evaluate variances among clusters. Also, a meta‐analysis using the method of cluster analysis was used to group the heritability estimates. Two clusters were obtained for each trait by different variables. It was observed, for all traits, that the heterogeneity of variance was significant between clusters and studies for genetic correlation estimates. The pooled estimates, adding the variance between clusters, for direct heritability estimates for ADG, DMI, RFI, MBW and FCR were 0.32 ± 0.04, 0.39 ± 0.03, 0.31 ± 0.02, 0.31 ± 0.03 and 0.26 ± 0.03, respectively. Pooled genetic correlation estimates ranged from ?0.15 to 0.67 among ADG, DMI, RFI, MBW and FCR. These pooled estimates of genetic parameters could be used to solve genetic prediction equations in populations where data is insufficient for variance component estimation. Cluster analysis is recommended as a statistical procedure to combine results from different studies to account for heterogeneity. 相似文献
80.
DO Kleemann JM Kelly LJ Arney IL Farley AJ Tilbrook SK Walker 《Reproduction in domestic animals》2014,49(6):894-898
Poor reproductive performance of Merino ewe flocks when mated to Border Leicester rams during spring may be due to seasonality of the Border Leicester breed. Two approaches were taken to test this assumption. Six young (12 months old) or six mixed‐age (12, 24 and ≥36 months old) Border Leicester rams were either treated or not treated with melatonin implants (2 × 2 design) 6 weeks before the four groups of rams were each put with approximately 300 Merino ewes for an 8‐week mating period. Implants were inserted in early September (experiment 1). The second approach was to yard or not yard ewes and mixed‐age rams on several occasions during the first 3 weeks of the mating period (experiment 2). Pregnancy rate and twinning percentage were assessed by ultrasonography. In experiment 1, melatonin treatment in young rams increased (p < 0.001) pregnancy rate from 5.0% to 92.6%, but mixed‐age rams did not respond (90.7% vs 89.5% for melatonin and non‐melatonin treatments, respectively). Twinning rate was similar (p > 0.05) for ewes mated to either melatonin or non‐melatonin‐treated young rams (36.8% vs 40.0%, respectively), whereas melatonin significantly improved (p < 0.05) twinning rate in those ewes mated to mixed‐age rams (49.1% vs 36.1%). After 6 weeks of melatonin treatment, scrotal circumference was greater (p < 0.05) in both young and mixed‐aged rams than in untreated counterparts. In experiment 2, yarding of ewes and rams overnight on several occasions early in the mating period reduced (p < 0.001) pregnancy rate compared with non‐yarded counterparts (89.5% vs 65.5%). Twinning rate was not affected (37.7% vs 36.1%, respectively). In summary, melatonin treatment of Border Leicester rams significantly improved flock reproductive performance in spring due to improved pregnancy rates with young rams and improved litter size with mixed‐age rams. 相似文献