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排序方式: 共有102条查询结果,搜索用时 18 毫秒
1.
Josiane C. Panisson Nathália C. Oliveira Cristina M. Sá-Fortes Adsos A. Passos Claudia C. da Silva Wagner A. G. Araújo Idael M. G. Lopes Gleison M. S. Costa Iara Q. Ataíde Bruno A. N. Silva 《Animal Science Journal》2021,92(1):e13592
Improvements in sow productivity have raised questions regarding dietary vitamin D recommendations. The present study aimed to evaluate the effects of the housing system with access to sunlight exposure and supplementation of 25-hydroxicholecalciferol on performance and serum levels of 25(OH)D3 in sows during gestation and lactation. Sows were distributed in an experimental design with two housing systems: gestation crates or gestation free-range system with external area for sunlight exposure; and two diets: 0 or 50 μg of 25-hydroxicholecalciferol kg−1. The use of 25-hydroxicholecalciferol tended (P = 0.052) to improve total born and influenced (P = 0.046) on number of born alive. Litter weight at birth was also increased (P = 0.01) by 25-hydroxicholecalciferol supplementation; 25-hydroxicholecalciferol supplementation and housing system (free-range with sunlight exposure) tended to increase weaning weight (P = 0.07) and litter daily gain (P = 0.051) during lactation. Exposure to sunlight and 25-hydroxicholecalciferol supplementation increased 25(OH)D3 serum levels when compared with control treatment during gestation (136.95 vs. 113.92 ng mL−1; P = 0.035) and lactation (120.29 vs. 88.93 ng mL−1; P = 0.026). In conclusion, the association of 25-hydroxicholecalciferol supplementation with exposure to sunlight during gestation improved significantly 25(OH)D3 serum levels and consequently performance traits in gestation and lactation. 相似文献
2.
RR Moura ES Lopes‐Junior DIA Teixeira IA Serova LE Andreeva LM Melo VJF Freitas 《Reproduction in domestic animals》2010,45(5):e101-e106
The objective of this study was to examine the effect of donor breed on pronuclear‐stage embryo yield to be used for DNA microinjection in a transgenesis goat program. Twelve Canindé and twelve Saanen goats were heat synchronized using a progestagen‐cloprostenol treatment. Forty‐eight hours before the sponge removal, superovulation was induced with a total administration of 4.4 mg/kg bodyweight NIH‐FSH‐P1, given twice daily in decreasing doses over 3 days. In addition, goats received 100 μg of GnRH and they were hand‐mated at 36 and 48 h after progestagen removal. Embryo recovery was performed by oviduct flushing at 72 h after sponge removal. Embryos were microinjected with a DNA construct and noticeable swelling of the nuclei was the criterion for successful microinjection. The total diameter, cytoplasm diameter, zona pellucida thickness and pronuclei diameter were measured for each microinjected embryo. A higher (p < 0.05) percentage of fertilized ova was observed in Canindé (89.9%) than Saanen (36.2%) goats. In addition, Canindé donors produced a higher percentage of pronuclear embryos when compared with Saanen: 72.5% vs 20.6% (p < 0.05), respectively. Successful microinjection was verified in 96.7% and 73.3% of times in Canindé and Saanen embryos, respectively (p < 0.05). Significant differences were observed for all morphometric parameters except for cytoplasm diameter. In conclusion, under our study experimental conditions, Canindé were more efficient than Saanen goats concerning the pronuclear embryo yield and manipulation. The use of Canindé goats in transgenesis programs could be increase the interest in their breeding and could be contribute to saving them from extinction. 相似文献
3.
Carvalho R Passos LM Martins AS 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2000,47(5):351-359
In this study, a multiplex polymerase chain reaction (PCR) procedure was developed for differentiation of strains and field isolates of equine herpesvirus type 1 (EHV-1) and type 4 (EHV-4). Specific oli-gonucleotide primers were combined to amplify the thymidine kinase (TK) gene region of EHV-1 and EHV-4, which would yield fragments of different lengths for each virus in the same amplification reaction. The specificity of the largest PCR amplicon for EHV-4 was confirmed by restriction digestion with HindIII. The multiplex PCR proved to be a fast and sensitive method for typing EHV-1 and EHV-4 isolates and for detection and differentiation of both viruses in field samples in which infectious virus is no longer available. The sensitivity was improved by combining cycling optimization and visualization of PCR products in ethidium bromide and silver-stained acrylamide gels. 相似文献
4.
Figueiredo JF Martins MS Ribeiro MF Passos LM 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2000,47(2):121-126
A panel of monoclonal antibodies was produced and characterized by an indirect fluorescent antibody test (IFAT), an enzyme-linked immunosorbent assay (ELISA) and Western blotting with the aim of identifying antigens of Babesia bovis. After fusion, the resultant hybrids were selected by the IFAT, cloned, maintained in culture in vitro, and cryopreserved in liquid nitrogen. Ten clones producing monoclonal antibodies were found to react against the entire merozoites, three reacted on the surface of the merozoites, and one clone reacted against the polar region of the merozoites. All monoclonal antibodies reacted in ELISA, with the optical density varying from 0.368 to 0.502 (cut off = 0.022). The bands recognized by the monoclonal antibodies in Western blotting had molecular weights ranging from 162 to 19 kDa. Four clones recognized a single band of 73 kDa, and another four did not react in Western blotting. 相似文献
5.
D.T. Passos D. Hepp J.C.F. Moraes & T.A. Weimer 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2007,124(3):157-162
In cattle, genetic markers at the leptin (LEP) gene and at those linked to the gene have been described as affecting calving interval (markers LEPSau3AI and IDVGA51), or daily weight gain (BMS1074 and BM1500). This work investigated the effect of these alleles on LEP mRNA levels in cattle subcutaneous and omental adipose tissues. A sample of 137 females of a Brangus‐Ibage beef cattle herd was analysed to evaluate the distribution of the polymorphisms; then, animals having at least one of the IDVGA51*181 (allele 181 at marker IDVGA51; six animals), LEPSau3AI*2 (four), BMS1074*151 (13), BM1500*135 (six) alleles and a control group composed of animals without any of these alleles (four animals) were submitted to surgery to obtain omental and subcutaneous adipose tissues. Leptin mRNA expression was quantified by TaqMan RT‐PCR, using 18S rRNA as internal control and adjusted for the effect of body condition score, through regression analysis. Omental fat had LEP gene expression 33% lower than the subcutaneous tissue. Carriers of IDVGA*181 and BMS1074*151 showed subcutaneous fat leptin mRNA levels higher than the controls. Leptin controls feed intake and coordinates reproduction; therefore, animals with higher LEP gene expression will probably have lower daily weight gain than others with similar forage offer and nutritional condition and probably will also have longer calving interval. 相似文献
6.
This study examined germination and dormancy in Galeopsis speciosa (Lamiaceae), a common summer annual weed in cold‐temperate areas. Seeds collected in southern Sweden were subjected to several experiments. The seeds were dormant at maturity. Seeds sown outdoors after collection produced a small number of seedlings that emerged early in the spring. After long cold stratification or stratification outdoors over two winters, the maximum germination was 40–50%; germination occurring over a wide range of temperatures. Warm stratification preceding cold stratification had no effect on germination, but repeated warm and cold periods seemed to promote germination. Gibberellic acid (GA) stimulated germination, but full germination was only achieved after more than 2 months of incubation at the most suitable temperature regime tested. Excised embryos grew and developed into normal seedlings. With these results, the species does not fit into the currently used system for seed dormancy classifications. The response to GA and the growth of excised embryos indicate non‐deep or intermediate physiological dormancy, but dormancy alleviation by stratification was not in line with the guiding principles for these classifications. Galeopsis speciosa has a strong dormancy that is sufficiently alleviated during the winter to allow germination of only part of a seed batch each year; hence a stepwise germination pattern occurs over a period of several years. 相似文献
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Cesar Ricardo Arruda Fernanda Ramiro Vanessa Faria Roberto Barcelos Daniel Pontes Fernanda Passos Fabiano Kaiser Karoline dos Santos Teixeira Aline Maria Serrano Aline Abreu Leticia Siqueira Danielle Teixeira Matheus Vezzone Mariana Polivanov Helena Castilhos Zuleica 《Journal of Soils and Sediments》2022,22(2):547-558
Journal of Soils and Sediments - This study consists of the evaluation of metals acute toxicity levels taking into consideration a hypothetic scenario of dam breaking and land deposition of two... 相似文献
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