Sperm subpopulations influence the pregnancy rates in cattle     

Myrian Megumy Tsunokawa Hidalgo  Ana Beatriz Marques de Almeida  Fábio Lucas Zito de Moraes  Rodrigo Yudi Palhaci Marubayashi  Fabiana Ferreira de Souza  Thales Ricardo Rigo Barreiros  Maria Isabel Mello Martins 《Reproduction in domestic animals》2021,56(8):1117-1127

This study aimed to study the characteristics and subpopulations of spermatozoa from bulls with low and high reproductive performance based on pregnancy rates. Based on historical records of pregnancy rate from four farms, 24 bulls were selected. Two groups were established, with low pregnancy rates (n = 12; LOW), including bulls that presented pregnancy rates <52.27% (33.33% to 51.81%); and a group with high pregnancy rates (n = 12; HIGH), with pregnancy rates >52.27% (52.27% to 69.64%), after fixed-time artificial insemination (FTAI). The thawed sperm straws were analysed to sperm kinetics, morphology, plasma membrane integrity and sperm subpopulations. The LOW group exhibited a higher proportion of static cells (p < .05). In contrast, the HIGH group showed greater percentages for membrane integrity and total and progressive motility, and cells with fast and medium velocity (p < .05). In the cluster procedures, four sperm subpopulations were established. The low-fertility bulls presented the highest percentage of subpopulation 2 (41.46%), characterized by slow and progressive spermatozoa. The high-fertility bulls exhibited the highest percentage of subpopulation 3 (37.17%), characterized by fast and nonlinear spermatozoa. Results from this study indicated that bulls with greater percentages of fast and nonlinear spermatozoa seem to have greater fertilization capacity and the subpopulations analysis can be considered a tool to identify ejaculates with high fertility.  相似文献   

Anti-enteropathogenic Escherichia coli immunoglobulin Y isolated from eggs laid by immunised Leghorn chickens     

Amaral JA  Tino De Franco M  Carneiro-Sampaio MM  Carbonare SB 《Research in veterinary science》2002,72(3):229-234

IgY, the egg yolk immunoglobulin, equivalent to the IgG from mammals, has been used in veterinary practice for passive immunisation against bacterial or viral infectious diseases. Enteropathogenic Escherichia coli (EPEC) is the main etiological agent of infantile diarrhoea in Brazil and other developing countries. Our aims were to isolate immunoglobulin IgY from egg yolk laid by EPEC -immunised Leghorn chickens and to study its reactivity to the antigens from this pathogen, including some virulence factors. Leghorn chickens were immunised with a bacterial suspension intramuscularly (three hens) or intravenously (three hens) or with PBS (two hens). Eggs were collected over a period of 17 weeks. IgY isolation procedures were carried out by salt precipitation (ammonium sulphate, in solid form) followed by centrifugations and dialysis. Final preparations were submitted to sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS - PAGE), enzyme-linked immunosorbent assay (ELISA) and immunoblotting. All immunised animals developed good levels of antibodies reactive to whole bacteria or lipopolysaccharide (LPS), in contrast to the control ones. Immunoblottings allowed the recognition of several antigenic fractions of bacterial antigens, some of which had a molecular weight compatible with bacterial virulence factors, confirming the efficacy of the immunisation and the adequacy of the method.  相似文献   

Effects of progestagen exposure duration on estrus synchronization and conception rates of crossbreed ewes undergoing fixed time artificial insemination     

Wanessa Blaschi  Paula A. Lunardelli  Luciana S.R. Marinho  Marilu C. Max  Gustavo M.G. Santos  Katia C. Silva-Santos  Fabiana A. Melo-Sterza  Hernan Baldassarre  Thales R. Rigo  Marcelo M. Seneda 《Journal of veterinary science (Suw?n-si, Korea)》2014,15(3):433-437

Synchronization of estrus and ovulation are of paramount importance in modern livestock improvement programs. These methods are critical for assisted reproduction technologies, including artificial insemination and embryo transfer, that can increase productivity. In the current study, subcutaneous implants containing norgestomet were placed for long (14 days), medium (9 days), and short (5 days) periods of time in 70 crossbred ewes undergoing fixed-time artificial insemination. The resulting effects on estrus synchronization and conception rates were subsequently evaluated. Among the synchronized ewes, 85.7% (60/70) underwent estrus over a period of 72 h after progestagen treatment ceased. The shortest mean interval between withdrawal of the device and onset of estrus (34.2 ± 8.9 h) was observed in the G14 days of P4 group (p < 0.05). The conception rate of the G14 days of P4 group was statistically higher than that of the other groups (83.3% vs. 60.9% vs. 47.8%; p < 0.05). In conclusion, 14 days of norgestomet treatment produced higher conception rates and a greater number of pregnancies at the beginning of the breeding season.  相似文献   

Agronomic characterization of autotetraploid banana plants derived from ‘Pisang Lilin’ (AA) obtained through chromosome doubling     

Cícera Maria do Amaral  Janay de Almeida dos Santos-Serejo  Sebastião de Oliveira e Silva  Carlos Alberto da Silva Ledo  Edson Perito Amorim 《Euphytica》2015,202(3):435-443

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Yield and nitrogen use efficiency of bell pepper grown in SLAB fertigated with different nitrogen rates     

Jose Maria da Silva  Paulo Cezar Rezende Fontes  Carla do Carmo Milagres  July Anne Amaral de Abreu 《Journal of plant nutrition》2020,43(18):2833-2843

Abstract

Adequate plant nutrition is important to reduce costs and increase the crop yield. This study tried to verify the influence of Nitrogen (N) on plant biomass production and the yield of bell pepper grown in SLAB; quantify the N use efficiency (NUE), and to quantify the residual N concentration in the substrate after the end of the crop cycle. The experiment was carried out in a protected environment. Pepper seedlings were transplanted to SLAB bags containing 40?dm³ of substrate. The treatments consisted of six N rates (0, 1.5, 3.0, 4.5, 6.0, and 7.5?g plant^?1) split into 10 fortnightly applications, in a randomized block design with four replications. The fruit yield was evaluated throughout the experiment and after the final harvest, the dry mass of leaves, stem, and root of the plant, the N content and accumulated, the residual nitrate and ammonium in the substrate, and the NUE were evaluated. The rate of 5.51?g plant^?1 of N, corresponding to 355.5?kg ha^?1, provided the maximum yield of commercial fruits of 1.57?kg plant^?1 or 101.2 t ha^?1. With increasing N rate, the residual nitrate concentration in the substrate increased and the NUE decreased.  相似文献   

Vitamin E composition of walnuts (Juglans regia L.): a 3-year comparative study of different cultivars     

Amaral JS  Alves MR  Seabra RM  Oliveira BP 《Journal of agricultural and food chemistry》2005,53(13):5467-5472

The tocopherol and tocotrienol composition of walnuts (Juglans regia L.) was determined for nine cultivars (cvs. Arco, Franquette, Hartley, Lara, Marbot, Mayette, Mellanaise, Parisienne, and Rego). Walnuts were harvested over three consecutive years from two different geographical origins (Bragan?a and Coimbra, Portugal), for a total of 26 samples. The methodology employed was a normal-phase high-performance liquid chromatography coupled to a series arrangement of a diode array detector followed by a fluorescence detector, allowing the simultaneous analysis of all tocopherols and tocotrienols. The analyses showed that all samples presented a similar qualitative profile composed of five compounds: alpha-tocopherol, beta-tocopherol, gamma-tocopherol, delta-tocopherol, and gamma-tocotrienol. gamma-Tocopherol was the major compound in all samples, ranging from 172.6 to 262.0 mg/kg, followed by alpha- and delta-tocopherols, ranging from 8.7 to 16.6 mg/kg and from 8.2 to 16.9 mg/kg, respectively. Multivariate analysis of the data obtained showed the existence of significant differences in composition among cultivars. These differences were also significant when cultivars were grouped by year of production, showing that besides genetic factors, the vitamin E composition was influenced by environmental factors.  相似文献   

Efficacy of topically applied ivermectin against Boophilus microplus (Canestrini, 1887) in cattle     

L G Cramer  L A Carvalho  A A Bridi  N K Amaral  R A Barrick 《Veterinary parasitology》1988,29(4):341-349

Systemic efficacy of ivermectin applied topically was evaluated against the cattle tick, Boophilus microplus. Twenty cattle with induced infestations were randomly allocated to five groups of equal size based on the numbers of engorged female ticks which fell through the slatted floor of individual pens during the 3 days prior to treatments. Control cattle were non-medicated. Cattle in three groups were given ivermectin at 200, 500 or 1000 mcg kg-1 in a topical formulation applied along the backline from the withers to the rump; cattle in the fifth group were given ivermectin in an injectable formulation subcutaneously at 200 mcg kg-1. Individual 24-h tick collections were made three times weekly for 5 weeks after treatment. Engorged female B. microplus were incubated to determine effects on reproduction. Based on the numbers of engorged female B. microplus collected following treatments, overall efficacy of ivermectin applied topically at 200, 500 and 1000 mcg kg-1 was 50, 85 and 91%, respectively, whereas ivermectin given at 200 mcg kg-1 subcutaneously was 80% effective. The index of reproduction for ivermectin given topically was reduced by 84, 94 and 95%, respectively, and that for ivermectin subcutaneously was 94%. No significant differences (P greater than 0.05) were found for these variables between ivermectin given topically at 500 or 1000 mcg kg-1 versus 200 mcg kg-1 given subcutaneously.  相似文献   

Variable number of tandem aminoacid repeats in adhesion-related CDS products in Mycoplasma hyopneumoniae strains     

de Castro LA  Rodrigues Pedroso T  Kuchiishi SS  Ramenzoni M  Kich JD  Zaha A  Henning Vainstein M  Bunselmeyer Ferreira H 《Veterinary microbiology》2006,116(4):258-269

The Mycoplasma hyopneumoniae genome contains at least 22 regions with a variable number of tandem nucleotide repeats (VNTRs) within coding DNA sequences (CDSs). In this work, the VNTR-containing CDSs were analysed in order to evaluate their degree of variation, possible correlations with antigenic properties, and their potential to be used as a basis for a strain typing PCR assay. We have analysed the VNTRs in five M. hyopneumoniae strains (J, 7448, 7422, PMS, and 232), based on published genomic sequences and on amplified and sequenced DNA segments. These VNTRs are distributed among 12 genes, most of which encode putative surface proteins, including known adhesins. The number of repeat units in any of the VNTRs is highly variable among the analysed strains, but they are, without exception, translationally in frame, and, therefore, code for a variable number of aminoacid repeats (VNTARs). These VNTARs determine putative structural, physicochemical and antigenic variations in the corresponding proteins, with potential implications for aspects associated to M. hyopneumoniae pathogenicity, such as cell adhesion and interactions with the host immune system. Considering that the characterized VNTARs are relatively stable, at least in vitro, and their sizes are strain-specific, we have developed a VNTR-based PCR assay for M. hyopneumoniae strain identification, useful for enzootic pneumonia (EP) diagnosis, strain typing, and distinction of circulating field isolates from vaccine strains in animals vaccinated against EP.  相似文献   

Critical disease components of common bacterial blight to effectively evaluate resistant genotypes of snap bean     

Roberto dos Santos Trindade  Rosana Rodrigues  Ant?nio Teixeira do Amaral Júnior  Leandro Sim?es Azeredo Gon?alves  Rogério Figueiredo Daher  Cláudia Pombo Sudré 《Journal of General Plant Pathology》2012,78(3):201-206

Common bacterial blight (CBB) caused by Xanthomonas axonopodis pv. phaseoli (Xap) is the main bacterial disease of snap bean. The present work aimed to select snap bean genotypes that are resistant to CBB based on three components of resistance: area under the disease progress curve, latent period, and lesion diameter on pods (DL). A completely randomized two-factor factorial design with six replications was used to evaluate leaves and pods of 14 snap bean and three common bean genotypes (PI 207262, BAC-6 and A-794) with high resistance to CBB. Two Xap isolates, 1394-98 and 775-90, were used to inoculate leaves and pods. Data were analyzed using nonparametric statistics. Significant differences were observed among the evaluated genotypes for all of the components of resistance, except for DL. The snap bean UENF 1482 demonstrated good performance in two disease resistance components. For this reason, this genotype can be recommended for use in breeding programs that aim to generate snap bean genotypes resistant to Xanthomonas axonopodis pv. phaseoli.  相似文献   

Forty years of soil research funded by the European Commission: Trends and future. A systematic review of research projects     

Cristina Arias-Navarro  P. Panagos  A. Jones  M. J. Amaral  A. Schneegans  M. Van Liedekerke  P. Wojda  L. Montanarella 《European Journal of Soil Science》2023,74(5):e13423

The European Green Deal with its high ambition has set the European Union (EU) on a promising path towards greater soil protection. The EU Soil Strategy 2030, the Biodiversity Strategy 2030, the Farm to Fork Strategy, the Zero Pollution, the Nature Restoration Law and the European Climate Law, among others, include actions to protect our soils. Research and Innovation (R&I) will play a key role in developing new knowledge and tools enabling the transition to healthy soils. The main aim of this paper is to analyse past and near-future trends in EU's funding for R&I on soil-related issues. For this purpose, a review of EU-funded soil projects was conducted based on the data available in the Community Research and Development Information Service and the official portal for European data. Our analysis shows that over the past 40 years, the EU has invested significantly in developing integrated knowledge about the relationships between soil functions and ecosystem services and how human-induced pressures affect soil health. Following the adoption of the EU Soil Thematic Strategy in 2006, there was an increase in research funding for soil-related research. Furthermore, our analysis also illustrates an interesting interplay of permanent and changing soil themes. The Horizon Europe Mission ‘A Soil Deal for Europe’, which aims to establish a network of 100 living labs and lighthouses to lead the transition towards healthy soils and safeguard human and planetary health by 2030, provides a further incentive for soil research. Together with the EU Soil Strategy 2030 and the new proposal for a Directive on Soil Monitoring and Resilience (Soil Monitoring Law), and the EU Soil Observatory (EUSO), the three instruments set up the political framework, concrete measures, and a monitoring system needed for the protection, restoration and sustainable use of soils.  相似文献