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91.
Matias Bermann Daniela Lourenco Vivian Breen Rachel Hawken Fernando Brito Lopes Ignacy Misztal 《Journal of animal science》2021,99(4)
The introduction of animals from a different environment or population is a common practice in commercial livestock populations. In this study, we modeled the inclusion of a group of external birds into a local broiler chicken population for the purpose of genomic evaluations. The pedigree was composed of 242,413 birds and genotypes were available for 107,216 birds. A five-trait model that included one growth, two yield, and two efficiency traits was used for the analyses. The strategies to model the introduction of external birds were to include a fixed effect representing the origin of parents and to use unknown parent groups (UPG) or metafounders (MF). Genomic estimated breeding values (GEBV) were obtained with single-step GBLUP using the Algorithm for Proven and Young. Bias, dispersion, and accuracy of GEBV for the validation birds, that is, from the most recent generation, were computed. The bias and dispersion were estimated with the linear regression (LR) method,whereas accuracy was estimated by the LR method and predictive ability. When fixed UPG were fit without estimated inbreeding, the model did not converge. In contrast, models with fixed UPG and estimated inbreeding or random UPG converged and resulted in similar GEBV. The inclusion of an extra fixed effect in the model made the GEBV unbiased and reduced the inflation. Genomic predictions with MF were slightly biased and inflated due to the unbalanced number of observations assigned to each metafounder. When combining local and external populations, the greatest accuracy can be obtained by adding an extra fixed effect to account for the origin of parents plus UPG with estimated inbreeding or random UPG. To estimate the accuracy, the LR method is more consistent among scenarios, whereas the predictive ability greatly depends on the model specification. 相似文献
92.
Mastrodi Salgado J Baroni Ferreira TR de Oliveira Biazotto F Dos Santos Dias CT 《Plant foods for human nutrition (Dordrecht, Netherlands)》2012,67(1):39-43
Antioxidants are compounds responsible for free radical scavenging in the body. They protect the organism from oxidative modification
of cells and tissues. These modifications have been associated with degenerative diseases, atherosclerosis and carcinogenesis.
Punica granatum displays high antioxidant potential due to the presence of phenolic compounds, which are capable of disease prevention. The
present study showed the highest antioxidant activity in pomegranate peel than in seeds and pulp. Based on these results,
pomegranate peel was used to produce dried extract that was added to commercial tomato juice and orange juice with strawberries.
Analysis to determine the content of phenolic compounds and antioxidant activity was performed on pomegranate pulp, seeds
and peel and in juices enriched with dried extract of pomegranate peel. The dried extract was responsible for a significant
increase in antioxidant activity of the juices, proportional to the concentrations added. However, although both flavors of
enriched juices displayed high antioxidant levels, the samples with higher dried extract concentrations received the lowest
scores from sensory analysis participants due to the characteristic astringent flavor of pomegranate peels. Therefore, to
obtain greater acceptance in the consumer market, we concluded that the maximum addition of dried pomegranate peel extract
is 0.5% in tomato juice and orange juice with strawberries. 相似文献
93.
Valerie J. Stull Mukata Wamulume Mwangala I. Mwalukanga Alisad Banda Rachel S. Bergmans Michael M. Bell 《Agriculture and Human Values》2018,35(4):867-883
Entomophagy—the practice of eating insects—has been touted as a means to combat undernutrition and food insecurity globally. Insects offer a nutritious, environmentally friendly alternative to resource-intensive livestock. But the benefits of edible insects cannot be realized if people do not choose to eat them. We therefore examine the social acceptability of edible insects in rural Zambia, where entomophagy is common but underexplored. Through a village case study, we show that edible insects are not valued equally, are understood socially, and seem to reflect and reinforce social values. We utilize grounded theory and ethnographic methods, including semi-structured interviews, focus groups, and observation to examine collective entomophagy beliefs. While we expected to see differentiation in perceptions across groups based on kinship, we demonstrate that social values related to class, urbanism, gender, and age emerge as more germane explanations for entomophagy perceptions, reflecting their social weight. By expanding on current apperception of entomophagy behavior, our findings inform future research and efforts to promote entomophagy through minilivestock farming. Systems designed to maximize output, minimize labor, and highlight benefits are more likely to be widely accepted. We do not anticipate tribal association will be the primary limitation on minilivestock adoption in this context. 相似文献
94.
Rachel C. Hector Marlis L. Rezende Khursheed R. Mama Eugene P. Steffey Heather K. Knych Ann M. Hess Juhana M. Honkavaara Marja R. Raekallio Outi M. Vainio 《Veterinary anaesthesia and analgesia》2017,44(4):755-765
Objective
To determine the effects of low and high dose infusions of dexmedetomidine and a peripheral α2-adrenoceptor antagonist, MK-467, on sevoflurane minimum alveolar concentration (MAC) in dogs.Study design
Crossover experimental study.Animals
Six healthy, adult Beagle dogs weighing 12.6 ± 0.9 kg (mean ± standard deviation).Methods
Dogs were anesthetized with sevoflurane in oxygen. After a 60-minute instrumentation and equilibration period, the MAC of sevoflurane was determined in triplicate using the tail clamp technique. PaCO2 and temperature were maintained at 40 ± 5 mmHg (5.3 ± 0.7 kPa) and 38 ± 0.5 ºC, respectively. After baseline MAC determination, dogs were administered two incremental loading and infusion doses of either dexmedetomidine (1.5 μg kg?1 then 1.5 μg kg?1 hour?1 and 4.5 μg kg?1 then 4.5 μg kg?1 hour?1) or MK-467 (90 μg kg?1 then 90 μg kg?1 hour?1 and 180 μg kg?1 then 180 μg kg?1 hour?1); loading doses were administered over 10 minutes. MAC was redetermined in duplicate starting 30 minutes after the start of drug administration at each dose. End-tidal sevoflurane concentrations were corrected for calibration and adjusted to sea level. A repeated-measures analysis was performed and comparisons between doses were conducted using Tukey's method. Statistical significance was considered at p < 0.05.Results
Sevoflurane MAC decreased significantly from 1.86 ± 0.3% to 1.04 ± 0.1% and 0.57 ± 0.1% with incremental doses of dexmedetomidine. Sevoflurane MAC significantly increased with high dose MK-467, from 1.93 ± 0.3% to 2.29 ± 0.5%.Conclusions and clinical relevance
Dexmedetomidine caused a dose-dependent decrease in sevoflurane MAC, whereas MK-467 caused an increase in MAC at the higher infusion dose. Further studies evaluating the combined effects of dexmedetomidine and MK-467 on MAC and cardiovascular function may elucidate potential benefits of the addition of a peripheral α2-adrenergic antagonist to inhalation anesthesia in dogs. 相似文献95.
96.
Matyas F Sreenivasan V Marbach F Wacongne C Barsy B Mateo C Aronoff R Petersen CC 《Science (New York, N.Y.)》2010,330(6008):1240-1243
Classical studies of mammalian movement control define a prominent role for the primary motor cortex. Investigating the mouse whisker system, we found an additional and equally direct pathway for cortical motor control driven by the primary somatosensory cortex. Whereas activity in primary motor cortex directly evokes exploratory whisker protraction, primary somatosensory cortex directly drives whisker retraction, providing a rapid negative feedback signal for sensorimotor integration. Motor control by sensory cortex suggests the need to reevaluate the functional organization of cortical maps. 相似文献
97.
In this study, 5/6 commercially available fungal culture media were comparable with respect to first growth, first colour change, and first sporulation when inoculated with three strains of Microsporum canis, one strain of Microsporum gypseum, and one strain of Trichophyton species when incubated at either 25°C or 30°C. Five of six plates showed 100% growth at both temperatures. Five of six plates showed 100% growth when inoculated with naturally infective M canis hairs and spores. One commercial product packaged as a self-sealing incubation plate showed growth in only 65.4% of times and the plates were prone to desiccation. M canis inoculated plates were incubated under four different light exposures (24h of light, 24h of dark, 12h light/12h dark, and room lighting) and no differences in growth or sporulation were noted. 相似文献
98.
99.
Rachel P. Atherton Martin O. Furr Harold C. McKenzie Anne M. Desrochers 《Journal of Equine Veterinary Science》2011,31(1):19-25
Colitis in the adult horse is a life-threatening clinical condition that can be caused by any of several enteric pathogens. This study was conducted to determine whether treating horses with plasma obtained from donors that were hyperimmunized against the common equine diarrheal pathogens Clostridium difficile, Clostridium perfringens, and Salmonella sp shortens the duration of diarrhea in acute colitis. To evaluate the efficacy of plasma treatment, 42 horses with acute onset of diarrhea were studied. Horses were enrolled if they were of age >1 year, duration of diarrhea at presentation was <72 hours, and they had not received equine plasma within the last 3 months. In addition, the serum cortisol concentrations of horses with acute diarrhea were studied.Horses were randomized to receive hyperimmunized plasma, control plasma (collected from nonimmunized horses), or no plasma therapy. Clinical parameters and fecal consistency were observed until resolution, discharge, or death, and complete blood counts (CBCs) and biochemical profiles were collected throughout the study. A total of 38 horses completed the study. The mean duration of diarrhea was 40.7 ± 9.8 (mean ± SEM) hours, 119.2 ± 56.1 hours, and 72.0 ± 24.5 hours for the hyperimmunized plasma, normal plasma (NP), and control groups, respectively. Using survival analysis techniques, this difference did not achieve statistical significance (P = .374). Serum cortisol was found to be increased in all horses at presentation and to decrease with time in all treatment groups. There was no difference in cortisol concentrations between the three treatment groups studied (P = .237). 相似文献
100.
Hayashi K Bhandal J Kim SY Rodriguez CO Entwistle R Naydan D Kapatkin A Stover SM 《Veterinary surgery : VS》2011,40(2):192-197
Objectives: To (1) describe vascular distribution in the grossly intact canine cranial cruciate ligament (CCL) using immunohistochemical techniques specific to 2 components of blood vessels (factor VIII for endothelial cells, laminin for basement membrane); and (2) compare the vascularity in different areas of interest (craniomedial versus caudolateral bands; core versus epiligamentous regions; and proximal versus middle versus distal portions) in the intact normal canine CCL. Study Design: In vitro study. Animals: Large, mature dogs (n=7) of breeds prone to CCL disease that were euthanatized for nonorthopedic conditions. Methods: Intact CCL were collected from fresh canine cadavers free from stifle pathology. CCL tissue was processed for immunohistochemistry and stained for factor VIII and laminin. Vascular density was determined by histomorphometric analysis. Results: Specific vascular staining was sparsely identified throughout the CCL; however, the proximal portion of the CCL appears to have a greater number of vessels than the middle or distal portion of the ligament. Conclusions: The CCL is a hypovascular tissue and its vascular distribution is not homogeneous. 相似文献