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排序方式: 共有316条查询结果,搜索用时 31 毫秒
51.
DG Riley CC Chase SW Coleman WA Phillips MF Miller JC Brooks DD Johnson TA Olson 《Journal of animal science》2012,90(7):2159-2166
The objectives of this work were to estimate heterosis and breed genetic effects for carcass quantity, quality, and palatability traits of steers (Bos spp.) produced from matings of Romosinuano, Brahman, and Angus cattle. Steers (n = 464) were weaned at 7 mo of age and transported to the Southern Great Plains where they grazed winter wheat for 6 mo and were then fed a finishing diet until serial slaughter after different days on feed (average 130 d). Carcass quality and quantity traits were measured; steaks (aged 7 d) were obtained for palatability evaluation. Heterosis was detected for BW, HCW, dressing percentage, LM area, and yield grade for all pairs of breeds. Generally, Romosinuano-Angus heterosis estimates were smallest, Romosinuano-Brahman estimates were intermediate, and Brahman-Angus heterosis estimates were largest. The direct Romosinuano effect was to decrease (P < 0.05) BW (-67 ± 16 kg), HCW (-48 ± 10 kg), dressing percentage (-1.4 ± 0.5 units), 12th rib fat thickness (-5.2 ± 0.8 mm), and yield grade (-0.9 ± 0.1), and to increase LM area per 100 kg HCW (3.6 ± 0.3 cm(2)/100 kg). Significant Brahman direct effects were detected for BW (34 ± 17 kg), HCW (29 ± 10 kg), dressing percentage (1.6 ± 0.6 %), LM area per 100 kg HCW (-3.3 ± 0.4 cm(2)/100 kg), and yield grade (0.6 ± 0.1). Significant Angus direct effects were to increase 12th rib fat thickness (3.8 ± 1 mm). Among sire breed means, Romosinuano had reduced (P = 0.002) marbling score (393 ± 9) than Angus, but greater mean sensory tenderness scores (5.8 ± 0.1), and reduced percentage Standard carcasses (10 ± 2%) than Brahman (P < 0.002). Angus sire breed means for marbling score (475 ± 10), overall tenderness (5.8 ± 0.1), and percentage Choice carcasses (75 ± 5%) were greater (P < 0.05) than Brahman sire breed means (360 ± 11, 5.4 ± 0.1, 31 ± 5%). From consideration only of characteristics of the end product of beef production, Romosinuano did not provide a clearly superior alternative to Brahman for U.S. producers, as they had some quality and palatability advantages relative to Brahman, but at lighter HCW. 相似文献
52.
ABSTRACTAims: To determine if an ELISA for measurement of IgA in equine serum could be used to measure concentrations of IgA in foal faeces and to determine correlations with concentrations in the milk of the dam.Methods: Faeces from 20 Welsh Cob and Welsh Pony foals and milk from their dams were collected within 12?hours (Day 0) and at 6 days after parturition (Day 6). On Day 6, faeces could not be collected from 2/20 foals, and milk samples could not be collected from 3/20 mares. An equine IgA ELISA validated for serum and plasma was used to measure concentrations of IgA in all samples in triplicate. The precision of the assay for each sample type was determined using modified CV.Results: IgA was not detectable in 7/20 Day 0 faecal samples and in 2/18 Day 6 faecal samples. For samples with detectable IgA, the mean modified CV was 10.5 (95% CI?=?6.0–15.0)% for Day 0 faecal samples, and was 6.8 (95% CI?=?4.3–9.4)% for Day 6 faecal samples. Median concentrations of IgA in faeces on Day 0 were lower than concentrations on Day 6 (0.7?mg/g vs. 37?mg/g dry matter; p?=?0.003). Concentrations of IgA in milk and faeces on Day 6 were statistically correlated (r?=?0.59; p?=?0.006).Conclusions and clinical relevance: The IgA ELISA showed acceptable precision when used to estimate concentrations of IgA in foal faeces during the first week of life, but IgA could not be detected in 37% of meconium samples collected on Day 0. This assay may be useful for investigation of the role of maternal milk IgA in the gastrointestinal tract of neonatal foals, but further assessment of both accuracy and precision of the ELISA is required. 相似文献
53.
Amber D. Goguen Shawn J. Riley John F. Organ Brent A. Rudolph 《Human Dimensions of Wildlife》2018,23(3):197-212
An increased societal focus on wildlife as food and recent policy deliberations regarding legal markets for wild-harvested meat are encouraging wildlife managers and researchers to examine the amount, use, and distribution of meat yielded through recreational hunting. We used responses to questions on the Michigan Deer Harvest Study to estimate the maximum yield of edible venison and assess hunters’ sharing behaviors. We estimated 11,402–14,473 metric tons of edible venison were procured during the 2013 hunting season. Of hunters who harvested a deer, 85% shared their venison. Hunters who shared did so with an average of 5.6 people (SD = 4.5). Sharing occurred most frequently within tight social networks: members of hunters’ households (69%), relatives (52%), and friends, neighbors, or coworkers (50%). In the absence of legal markets, venison is distributed widely by hunters and greatly amplifies the number of people benefiting from hunting. Nonetheless, we also identified the potential breadth of exposure to disease or contaminants from wild-harvested meat. 相似文献
54.
Pond experiments with one treatment per pond are discussed for their sources of variability. Replication of treated ponds, randomization of treatment allocation to ponds and the importance of independence between ponds are emphasized for efficient estimation of both treatment and inherent pond differences. Appropriate models are given for the analysis of data for pond experiments with whole-pond treatments. Corresponding analyses of variance are given to illustrate the estimation of differences between treatments, between ponds and between fish within ponds. Appropriate significance tests for treatment effects are demonstrated to avoid pseudoreplication, the incorrect use of within-pond variation. Using a fertilizer experiment, simple graphical methods are presented for examining between- and within-pond variation to identify ponds with unusual data, and to determine adequacy of design and appropriate analyses. 相似文献
55.
56.
H. Bindumadhava L. Sharma R. M. Nair H. Nayyar J.J Riley W Easdown 《Journal of Crop Improvement》2018,32(3):418-430
Increasing global air temperatures, along with rising CO2 levels, are causing concerns about reducing available freshwater resources and altering cropping patterns. They may influence overall growth and production pattern of crop plants. These likely changes would become major limiting factors for future sustainable food production largely in the tropics and subtropics. Thus, understanding physiological responses hold the key to determining the functional relationship between the environment and crop performance. We explore here the impact of rising CO2 on the growth and yield traits of a few selected high-temperature (HT)-tolerant mungbean lines, which we earlier screened for HT tolerance using a physiological assay under managed growth conditions. The HT-tolerant lines grown under elevated CO2 levels (550 and 700 μL L?1) showed a considerable improvement in growth rates (13.5%, 67.8%, and 46.5% in plant height, leaf area, and total dry matter, respectively) and pod and seed yield (48.7% and 31.7%, respectively), compared to local checks under the same environments. Interestingly, the symptoms of accelerated pod maturity were also observed in most of these lines. The outcome of the study would undoubtedly open up opportunities for increased yield potentials of legumes under the conditions of the warming climate and elevated levels of carbon dioxide. 相似文献
57.
Baumgarner BL Riley CP Sepulveda MS Brown PB Meyer JL Adamec J 《Fish physiology and biochemistry》2012,38(2):319-327
Short-term starvation has been linked to in vivo protein degradation in liver of rainbow trout (Oncorhynchus mykiss). However, it is unclear whether this proposed increase in protein degradation is followed by programmed cell death (apoptosis)
in liver of starved trout. A preliminary study in our laboratory revealed an isoform of glyceraldehyde-3-phosphate dehydrogenase
(GAPDH) protein that increased 4.5-fold in liver of starved trout. GAPDH is a glycolytic enzyme involved in other cellular
functions, including apoptosis. Increased intracellular nitric oxide (NO) promotes nuclear translocation of GAPDH that is
associated with increased apoptosis in mammals. If GAPDH protein is associated with apoptosis in rainbow trout, it could potentially
be used as a biomarker of cellular stress in liver of teleost fish species. The purpose of this study was to determine whether
increased GAPDH protein expression in liver of starved rainbow trout is associated with NO-induced apoptosis. Targeted proteomic
analysis using multiple reaction monitoring (MRM) was used to determine the level of GAPDH in nuclear and cytoplasmic fractions
and inducible nitric oxide synthase (iNOS) in cell lysates. Dot blot and DNA fragmentation analyses were conducted to evaluate
protein S-nitrosylation and apoptosis, respectively. Results showed that cytoplasmic GAPDH was 3.4-fold higher in liver of
starved versus fed rainbow trout but could not be detected in nuclear fractions. Starvation significantly reduced hepato-somatic
index but had no effect on iNOS protein expression, protein S-nitrosylation, or apoptosis. Our results indicate that starvation
promoted significant reduction in liver mass that was not associated with increased apoptosis or NO-induced stress and that
greater GAPDH concentration in liver of starved rainbow trout was located primarily in the cytoplasm. 相似文献
58.
59.
Alex Bukoski PhD DVM Matthew Winter DVM DACVR Carsten Bandt DVM DACVECC Mary Wilson RT CV MR CT Andre Shih DVM DACVA 《Journal of Veterinary Emergency and Critical Care》2010,20(4):393-397
Objective – To compare the placement feasibility and amount of bone trauma induced by 3 intraosseous (IO) access techniques in cats: an automatic impact penetration device (A), an automatic rotary insertion device (B), and a manual IO needle (C). Design – Prospective ex vivo study. Setting – University. Animals – Eighteen adult mixed breed feline cadavers. Interventions – Cadavers provided 72 total IO insertion locations divided equally between the right and left humerus and tibia. The 3 IO techniques were randomly allocated to these locations. Time to successful insertion, ease of insertion, and success rate were recorded. Each insertion site was analyzed for the number of bone fragments and defect diameter by computed tomography. Measurements and Main Results – Device B had lower time of insertion (P=0.01) compared with devices A and C. Device B had better ease of insertion scores (P<0.01) compared with devices A and C. No differences were detected between insertion sites (tibia versus humerus). No differences in the number of bone fragments, defect diameter, or success rate were detected among devices (P=0.06, 0.31, and 0.14, respectively). Conclusions – All 3 IO access methods evaluated yield acceptable results. Device B is significantly faster and easier to place in cat cadavers when compared with other methods. 相似文献
60.