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91.
92.
This work addresses to the genetic analysis and selection in populations where the whole genotypic value is transmitted through generations, using grapevine yield data as a case study. Several models were applied to different types of data sets. The individual and mean year yield and the balanced and unbalanced data resulting from various experimental designs (completely randomized, randomized complete block and row–column) were used. The aims of present work were to study: (1) the applicability of a generalised measure of broad-sense heritability to evaluate the success of the genotypic selection and compare it with the classical approach; and (2) the effect of different models on the accuracy and precision of the genotypic variance component and on the generalised broad-sense heritability estimates. The results showed that the computation of a measure of generalised broad-sense heritability is very feasible and useful for evaluating the efficiency of genotypic selection. In this study, 88 % of the fitted models did not comply with the standards for applying the classical concept of heritability. The differences between both the classical and generalised broad-sense heritability estimates increased with the complexity of the model. Higher broad-sense heritability estimates were consistently obtained with the mean years. The most accurate and precise estimates of the genetic parameters were obtained with the spatial models. Finally, the genotypic variance component of yield and the generalised broad-sense heritability were consistently significant for all grapevine varieties. 相似文献
93.
Fábio Raphael Pascoti Bruhn Débora Oliveira Daher Edna Lopes Jonata Mello Barbieri Christiane Maria Barcellos Magalhães da Rocha Antônio Marcos Guimarães 《Tropical animal health and production》2013,45(5):1093-1098
Neosporosis is an infectious disease caused by Neospora caninum, an obligate intracellular cyst-forming protozoan considered a major cause of miscarriage in dairy cattle in many parts of the world. This cross-sectional study evaluated the relationship between reproductive abnormalities and seropositivity to N. caninum in 1,204 dairy cows from 40 farms located in the state of Minas Gerais, southeastern Brazil. Producers were interviewed, and blood samples were collected to perform indirect immunofluorescence tests (IFAT 1:200). Association between reproductive abnormalities and seropositivity in cattle was evaluated with generalized estimating equations. The true herd-level seroprevalence of N. caninum was 95 % (83.3–99.1), while the individual-level true seroprevalence was 21.6 % (19.2–24.2). Several reproductive abnormalities were significantly associated with seropositivity to N. caninum: occurrence of repeated estrus (p?=?0.02; OR?=?3.84; 95 % CI?=?1.239–11.893), repeated miscarriages (p?=?0.001; OR?=?2.54; 95 % CI?=?1.423–5.402), and temporary anestrus (p?=?0.001; OR?=?3.44; 95 % CI?=?1.976–5.994). Furthermore, loose dogs (p?=?0.041; OR?=?2.20; 95 % CI?=?1.033–4.672) when fed raw meat (p?=?0.001; OR?=?1.91; 95 % CI?=?1.443–2.519) are risk factors for N. caninum infection. We observed that seropositivity to N. caninum in cattle increases risk of miscarriage by almost twice throughout the reproductive life of cows (p?=?0.004; OR?=?1.978; 95 % CI?=?1.249–3.131). Serologic evidence in this study indicates that N. caninum infection is widely distributed among dairy herds and significantly associated with reproductive disorders, especially miscarriage, repeated estrus, and temporary anestrus. 相似文献
94.
Patrícia Aparecida Cardoso da LUZ Paulo Ramos da Silva SANTOS Cristiana ANDRIGHETTO André Mendes JORGE Ant?nio Chaves de ASSIS NETO 《The Journal of reproduction and development》2013,59(1):14-17
Buffalo are an economically important source for meat and milk production, especially in
Brazil. However, important aspects of their biology remain unknown thus far. Herein, we
describe the reproductive characteristics of male Murrah buffalo (Bubalus
bubalis) raised under extensive management conditions by applying biometrics
associated with testicular weight. We analyzed seven males, divided into two groups: G1,
which consisted of four 18-month-old animals, and G2, which consisted of three
24-month-old animals. Testicular development occurs slowly in Murrah buffalo, suggesting a
delay of sexual maturity. The biometric testicular parameters analyzed were scrotal
circumference, testicular weight, testicular length, testicular width, testicular
thickness and testicular circumference. Our data indicate strong correlations between SC,
age and body weight, and additional significant relationships were identified between body
weight, age and other testicular parameters. Thus, these parameters are suitable
indicators when selecting bulls for breeding purposes. 相似文献
95.
Barbarella Matos de Macchi Farlen José Bebber Miranda Fernanda Silva de Souza Eulógio Carlos Queiroz de Carvalho Ant?nio Peixoto Albernaz José Luiz Martins do Nascimento Renato Augusto DaMatta 《Veterinary research》2013,44(1):8
Malaria is a serious infectious disease caused by parasites of the Plasmodium genus that affect different vertebrate hosts. Severe malaria leads to host death and involves different pathophysiological phenomena such as anemia, thrombocytopenia and inflammation. Nitric oxide (NO) is an important effector molecule in this disease, but little is known about its role in avian malaria models. Plasmodium gallinaceum- infected chickens were treated with aminoguanidine (AG), an inhibitor of inducible nitric oxide synthase, to observe the role of NO in the pathogenesis of this avian model. AG increased the survival of chickens, but also induced higher parasitemia. Treated chickens demonstrated reduced anemia and thrombocytopenia. Moreover, erythrocytes at different stages of maturation, heterophils, monocytes and thrombocytes were infected by Plasmodium gallinaceum and animals presented a generalized leucopenia. Activated leukocytes and thrombocytes with elongated double nuclei were observed in chickens with higher parasitemia; however, eosinophils were not involved in the infection. AG reduced levels of hemozoin in the spleen and liver, indicating lower inflammation. Taken together, the results suggest that AG reduced anemia, thrombocytopenia and inflammation, explaining the greater survival rate of the treated chickens. 相似文献
96.
Sousa C Fernandes F Valentão P Rodrigues AS Coelho M Teixeira JP Silva S Ferreres F Guedes de Pinho P Andrade PB 《Journal of agricultural and food chemistry》2012,60(21):5380-5387
Brassica oleracea L. var. costata DC leaves and Pieris brassicae L. larvae aqueous extracts were assayed for their potential to prevent/induce DNA damage. None of them was mutagenic at the tested concentrations in the Ames test reversion assay using Salmonella His(+) TA98 strains, with and without metabolic activation. In the hypoxanthine-guanine phosphoribosyltransferase mutation assay using mammalian V79 fibroblast cell line, extracts at 500 μg/mL neither induced mutations nor protected against the mutagenicity caused by methyl methanesulfonate (MMS). In the comet assay, none of the extracts revealed to be genotoxic by itself, and both afforded protection, more pronounced for larvae extracts, against MMS-induced genotoxicity. As genotoxic/antigenotoxic effects of Brassica vegetables are commonly attributed to isothiocyanates, the extracts were screened for these compounds by headspace-solid-phase microextraction/gas chromatography-mass spectrometry. No sulfur compound was detected. These findings demonstrate that both extracts could be useful against damage caused by genotoxic compounds, the larvae extract being the most promising. 相似文献
97.
António Alves Soares Maria Teresa Pinho José Tomás Albergaria Valentina Domingues Maria da Concei??o M. Alvim-Ferraz Paolo De Marco Cristina Delerue-Matos 《Water, air, and soil pollution》2012,223(5):2601-2609
Soil vapor extraction (SVE) is an efficient, well-known and widely applied soil remediation technology. However, under certain conditions it cannot achieve the defined cleanup goals, requiring further treatment, for example, through bioremediation (BR). The sequential application of these technologies is presented as a valid option but is not yet entirely studied. This work presents the study of the remediation of ethylbenzene (EB)-contaminated soils, with different soil water and natural organic matter (NOMC) contents, using sequential SVE and BR. The obtained results allow the conclusion that: (1) SVE was sufficient to reach the cleanup goals in 63% of the experiments (all the soils with NOMC below 4%), (2) higher NOMCs led to longer SVE remediation times, (3) BR showed to be a possible and cost-effective option when EB concentrations were lower than 335?mg?kg soil ?1 , and (4) concentrations of EB above 438?mg?kg soil ?1 showed to be inhibitory for microbial activity. 相似文献
98.
Sampaio Fernando Antônio Rebouças Teixeira Filho Marcelo Carvalho Minhoto da Silva Oliveira Carlos Eduardo Jalal Arshad Boleta Eduardo Henrique Marcandalli de Lima Bruno Horschut Rosa Poliana Aparecida Leonel Galindo Fernando Shintate de Souza Jeferson Silva 《Journal of Crop Science and Biotechnology》2021,24(4):429-439
Journal of Crop Science and Biotechnology - The rhizobacteria of genus Azospirillum and Bacillus are effective at fixing atmospheric nitrogen, promote plant growth and can largely contribute to... 相似文献
99.
Benjamín Costas Cláudia Aragão Jorge Dias António Afonso Luís E. C. Conceição 《Fish physiology and biochemistry》2013,39(5):1141-1151
Amino acids (AA) regulate key metabolic pathways, including some immune responses. Therefore, this study aimed to assess whether an increased availability of dietary AA can mitigate the expected increase in plasma cortisol and metabolites levels due to high stocking density and its subsequent immunosuppression. Senegalese sole (Solea senegalensis) were maintained at low stocking density (LSD; 3.5 kg m?2) or high stocking density (HSD; 12 kg m?2) for 18 days. Additionally, both treatments were fed a control or a high protein (HP) diet (LSD, LSD HP, HSD and HSD HP). The HP diet slightly increased the levels of digestible indispensable AA, together with tyrosine and cysteine. HSD was effective in inducing a chronic stress response after 18 days of treatment since fish held at HSD presented higher plasma cortisol, glucose and lactate levels. Moreover, this increase in stress indicators translated in a decrease in plasma lysozyme, alternative complement pathway (ACP) and peroxidase activities, suggesting some degree of immunosuppression. Interestingly, while plasma glucose and lactate levels in HSD HP specimens decreased to similar values than LSD fish, plasma lysozyme, ACP and peroxidase activities increased, with even higher values than LSD groups for ACP activity. It is suggested that the HP diet may be used as functional feed since it may represent a metabolic advantage during stressful events and may counteract immunosuppression in sole. 相似文献
100.
Paula S. Coelho Luísa Valério António A. Monteiro 《European journal of plant pathology / European Foundation for Plant Pathology》2009,125(2):179-188
Downy mildew caused by the oomycete Hyaloperonospora parasitica (formerly Peronospora parasitica) is a worldwide foliar disease of Brassica vegetables, which may cause seedling loss in the nurseries and damage to adult
plants in the field. Disease symptoms start from the lower leaves and progress upwards. Three experiments were conducted under
controlled environment conditions, using inoculated leaf discs, to determine the influence of leaf position, plant age, and
leaf age on the expression of resistance to downy mildew in various Brassica oleracea genotypes. The upper leaves were more resistant than the lower leaves when 7–19 week-old plants of broccoli and Tronchuda
cabbage were tested. Broccoli lines ‘PCB21.32’ and ‘OL87123-2’ were fully susceptible at the cotyledon stage, showed a clear
resistance increase from lower to upper leaves at 6 weeks and ‘PCB21.32’ was fully resistant 16 weeks after sowing. Immature
leaves were more resistant than adjacent fully expanded mature leaves. Susceptibility increased with leaf age when the same
leaf was tested at two to 4-week intervals. Leaf age and upper-leaf position on the stem had opposite effects on disease score,
since younger leaves collected from lower positions and older leaves collected from upper positions tended to score similarly
in compatible interactions. The progression of downy mildew from the base of the plant upwards on B. oleracea in the field could be due to differences in leaf resistance in addition to environmental variation. To maximise the expression
of a compatible reaction in adult plants lower leaves of Brassica plants that are at least 12 weeks-old should be used. 相似文献