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SUMMARY: The biological basis for meat production in livestock animals is localized in the muscles, where lean meat production is under the genetic control of tissue-specific and more ubiquitously operating genes. The muscle tissue-specific MyoD gene family is at the centre of the genetic regulation of myoblast proliferation and differentiation into myofibres. The regulation of embryonic muscle tissue formation (development) by the MyoD genes is duscussed in the context of livestock animals used in meat production. The possibility that the MyoD genes could be useful candidate genes for breeding is discussed. It is concluded that marker assisted selection (MAS) using markers in functional genes is advantageous over MAS using associated markers. ZUSAMMENFASSUNG: Genetische Regulierung der Fleischproduktion bei der embryonalen Muskelbildung - Ein Literaturüberblick Die biologische Grundlage für Fleischproduktion, lokalisiert in den Muskeln, steht unter genetischer Kontrolle durch gewebsspezifische una mehr ubiquit?r arbeitende Gene. Die gewebsspezifische MyoD Genfamilie in den Muskeln befindet sich im Zentrum der genetischen Regulierung des Prozesses der Myoblastteilung und Differenzierung zu Myofasern. Die Ubersicht betrifft Regulierung der Bildung des embryonalen Muskelgewebes (Entwicklung) mit Hilfe der MyoD Gene. Die M?glichkeit, da? MyoD Gene erfolgreiche Kandidatengene für Tierzüchtung sein k?nnen, wird besprochen. 'Marker-assisted selection' (MAS) mit Hilfe von Markern funktioneller Gene sollte vorteilhafter sein als MAS mit gekoppelten DNA-Sequenzen. RéSUMé: Régulation génétique de la production de viande par la formation embryologique des muscles - un résumé La base biologique de la production de viande dans les animaux d'élevage se situe dans les muscles, là où la production de viande maigre est sous contr?le génétique de gènes générals et tissu-spécifiques. La famille des gènes muscle-spécifiques MyoD forme le centre de la régulation des procès de prolifération des myoblastes et de différenciation vers les myofibres. Le but de cet article rétrospectif est de situer la discussion sur la régulation de la formation embryologique des muscles par les gènes MyoD dans le cadre de l'élevage. La possibilité que les gènes MyoD soient des gènes candidats utiles pour l'élevage sera discutée. La conclusion faite est que 'marker assisted selection' (MAS) en employant des marquers situés dans des gènes fonctionnels a plus d'avantages que MAS avec des marquers associés. 相似文献
3.
A survey of northern Victorian dairy farmers to investigate dairy calf management: colostrum feeding and management
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Objectives
To describe colostrum management practices carried out in northern Victorian dairy herds and to identify weaknesses in these areas that may affect calf health and welfare by comparing the results with the current industry recommendationsMethods
A questionnaire to obtain information about colostrum management and calf‐rearing practices was sent to commercial dairy farming clients of Rochester Veterinary Practice between June and September 2013. The questionnaire consisted of a general herd overview and colostrum harvesting practices.Results
The response rate was 39% (58/150). Many dairy producers were not meeting the current industry recommendations in the following areas: (1) time of removal calf from the dam, (2) relying on calf suckling colostrum from the dam to achieve adequate passive transfer, (3) failing to supplement calves with colostrum, (4) feeding inadequate volumes of colostrum, (5) delayed colostrum harvesting, (6) pooling of colostrum, (7) failing to objectively assess colostrum quality or relying on visual assessment and (8) storing colostrum for a prolonged periods of time at ambient temperatures.Conclusion
The results from this survey highlight the need for greater awareness of industry standards for colostrum management and feeding hygiene.4.
The effect of adipocyte and heart fatty acid-binding protein genes on intramuscular fat and backfat content in Meishan crossbred pigs 总被引:46,自引:0,他引:46
Gerbens F de Koning DJ Harders FL Meuwissen TH Janss LL Groenen MA Veerkamp JH Van Arendonk JA te Pas MF 《Journal of animal science》2000,78(3):552-559
Effects of genetic variation in porcine adipocyte and heart fatty acid-binding protein genes, A-FABP and H-FABP, respectively, on intramuscular fat (IMF) content and backfat thickness (BFT) were examined in F2 crossbreds of Meishan and Western pigs. The involvement of each FABP gene in IMF accretion was studied to confirm previous results for Duroc pigs. The F2 crossbred pigs were genotyped for various markers including microsatellite sequences situated within both FABP genes. Linkage analysis assigned the A-FABP and H-FABP genes to marker intervals S0001-S0217 (20 cM) on SSC4 and Sw316-S0003 (16.6 cM) on SSC6, respectively, refining previous chromosomal assignments. Next, the role of both chromosome regions/genes on genetic variation in IMF content and BFT was studied by 1) screening SSC4 and SSC6 for QTL affecting both traits by performing a line-cross analysis and 2) estimation of the effect of individual A-FABP and H-FABP alleles on both traits. In the first analysis, suggestive and chromosome-wise significant evidence for a QTL affecting IMF was detected on SSC6. The H-FABP gene is a candidate gene for this effect because it resides within the large region containing this putative QTL. The second analysis showed a considerable but nonsignificant effect of H-FABP microsatellite alleles on IMF content. Suggestive evidence for a QTL affecting BFT was found on SSC6, but H-FABP was excluded as a candidate gene. In conclusion, present and previous results support involvement of H-FABP gene polymorphisms in IMF accretion independently from BFT in pigs. Therefore, implementation of these polymorphisms in marker-assisted selection to control IMF content independently from BFT may be considered. In contrast to previous findings for Duroc pigs, no evidence was found for an effect of the A-FABP gene on IMF or BFT in this population. 相似文献
5.
Morphometry,Morphology and Ultrastructure of Ring‐tailed Coati Sperm (Nasua nasua Linnaeus, 1766)
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HVR Silva FF Magalhães LR Ribeiro ALP Souza CIA Freitas MF de Oliveira AR Silva LDM Silva 《Reproduction in domestic animals》2015,50(6):945-951
The ring‐tailed coati (Nasua nasua) is a procyonid whose population is in sharp decline. Therefore, studies are needed to better understand the reproduction of this animal. For this reason, this study aimed to evaluate the morphology, morphometry and sperm ultrastructure of ring‐tailed coati sperm. Four captive adult males were used for this study. Slides stained with Bengal Rose were used for the morphometric and morphologic analyses. The length and width of the head were measured, as well as the length of the midpiece and tail and the total length of the sperm. Scanning electron microscopy and transmission electron microscopy were used for the ultrastructural analyses. The most obvious morphological abnormalities observed were coiled tails (6.1 ± 8.7%) and the lack of acrosomes (5.4 ± 4.4%). Regarding the morphometry, the measurements of the head (length × width), midpiece (length) and tail (length) were (mean ± SD) 6.2 ± 0.4 × 8.1 ± 0.6 μm, 14.1 ± 0.5 and 63.9 ± 4.1 μm, respectively, and the total length of the sperm was 86.1 ± 4.3 μm. Through electron microscopy, the presence of electron‐lucent points in the nucleus and the presence of approximately 55 mitochondrial spirals in the midpiece were identified. The data obtained in this study provide detailed information on the sperm characteristics of coatis and may inform future research on germplasm conservation, both for this species and other threatened procyonids. 相似文献
6.
The effect of footrot on body weight and wool growth of sheep 总被引:1,自引:0,他引:1
Body weight and traits associated with production of wool were measured over a 2-year period between 1985 and 1987 in south-western New South Wales in a flock of Merino wethers experimentally infected with footrot. The disease was allowed to spread freely amongst 150 of the flock but kept at very low prevalence in the remaining 50 by preventive footbathing during transmission periods. Severe, underrunning footrot had a significant adverse effect on body weight, for each year of the trial. Body weight was most severely reduced at times of the year when footrot was spreading among animals and lesions were severe. The mean body weight of the infected group at the end of the 2 years of observation was 7.3 kg (11.6%) below that of the control group. Footrot also depressed wool growth, with the mean clean fleece weight of the infected group being 0.4 kg (8%) lighter than that of the controls at each of the 2 annual shearings. There were no consistent differences between the groups for the other wool characteristics measured. 相似文献
7.
The local effects of isolated magnetic adatoms on the electronic properties of the surface of a superconductor were studied with a low-temperature scanning tunneling microscope. Tunneling spectra obtained near magnetic adsorbates reveal the presence of excitations within the superconductor's energy gap that can be detected over a few atomic diameters around the impurity at the surface. These excitations are locally asymmetric with respect to tunneling of electrons and holes. A model calculation based on the Bogoliubov-de Gennes equations can be used to understand the details of the local tunneling spectra. 相似文献
8.
Pasławska U Noszczyk-Nowak A Kungl K Bioły K Popiel J Nicpoń J 《Polish journal of veterinary sciences》2006,9(4):253-257
Disorders of the thyroid gland activity are the most commonly encountered disturbances of endocrine origin in the dog. Hypo- or hyperthyroidism may disturb the function of the cardiovascular system and cause arrhythmias. The aim of this study was to evaluate the influence of thyroid gland activity on electrocardiogram (ECG) picture in the dog by comparing ECG curves of healthy dogs, dogs with hypothyroidism and dogs with cardiac insufficiency caused by endocardiosis of the mitral valve. The study was performed on 38 dogs, patients of the Department of Internal and Parasitic Diseases with Clinic for Horses, Dogs and Cats in Wroc?aw. The animals were assigned to 3 groups: Group I--control group, 13 clinically healthy dogs; Group II--14 dogs with diagnosed cardiac insufficiency caused by endocardiosis of the mitral valve; Group III--11 dogs with hypothyroidism. Clinical examination of the animals was conducted according to the following pattern: anamnesis, general clinical examination, cardiological examination (ECG, USG of the heart) and laboratory analysis (triacylglycerydes, cholesterol, T3, T4, FT4). In this study, the significant influence of thyroid gland activity on ECG picture of the evaluated dogs was found. In the dogs with hypothyroidism a decrease in the sino-atrial node activity was observed, which led to decreased heart rate. In dogs with hypothyroidism, the innerheart conduction was reduced, which was demonstrated by prolongation of the P wave, QRS complex and the QT interval. 相似文献
9.
M F te Pas J W Freriksen A J van Bijnen C L Gerritsen T J van den Bosch F H Harders F J Verburg A H Visscher K H de Greef 《Domestic animal endocrinology》2001,20(3):165-184
Selection for increased growth rate or decreased back fat thickness results in concomitant changes in endocrine and metabolic status. Growth hormone (GH) changes in blood plasma concentration related to selection for growth rate and fat deposition were reported in pigs. The molecular mechanisms regulating selection-induced changes in GH plasma concentration remain largely unknown. We investigated selection-associated changes in GH axis parameters in 2 pig lines selected for increased growth rate (F-line), or decreased back fat thickness (L-line), respectively. First, we investigated selection-associated changes in GH pulse parameters. In both selection lines we found each generation a declining GH peak maximum concentration and area under the GH curve. GH pulse width was not associated with generation number. In both lines generation number was associated with a declined pulse interval, indicating that the number of pulses per day increased on average with 1 pulse per 24 h per generation. Second, plasma concentration of GH axis related Insulin-like growth factor-I (IGF-I) and insulin were investigated. Plasma IGF-I concentration was not associated with generation number in the F-line. Mean plasma insulin concentration declined each generation in both lines. Third, we investigated changes in GH and Pit-1 mRNA levels. In both selection lines GH and Pit-1 mRNA levels increased approximately 50% each generation. The high SD of the GH mRNA levels in both lines may suggest that the GH mRNA levels are pulsatile in vivo. We postulate a molecular mechanism that may explain how selection is associated with increased GH mRNA levels and GH pulse numbers, while lowering GH release per pulse. 相似文献
10.