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1.
Microb Ecol ; 81(1): 67-77, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32561945

RESUMO

Shiga toxin-producing Escherichia coli (STEC) are foodborne bacterial pathogens, with cattle a significant reservoir for human infection. This study evaluated environmental reservoirs, intermediate hosts and key pathways that could drive the presence of Top 7 STEC (O157:H7, O26, O45, O103, O111, O121 and O145) on pasture-based dairy herds, using molecular and culture-based methods. A total of 235 composite environmental samples (including soil, bedding, pasture, stock drinking water, bird droppings and flies and faecal samples of dairy animals) were collected from two dairy farms, with four sampling events on each farm. Molecular detection revealed O26, O45, O103 and O121 as the most common O-serogroups, with the greatest occurrence in dairy animal faeces (> 91%), environments freshly contaminated with faeces (> 73%) and birds and flies (> 71%). STEC (79 isolates) were a minor population within the target O-serogroups in all sample types but were widespread in the farm environment in the summer samplings. Phylogenetic analysis of whole genome sequence data targeting single nucleotide polymorphisms revealed the presence of several clonal strains on a farm; a single STEC clonal strain could be found in several sample types concurrently, indicating the existence of more than one possible route for transmission to dairy animals and a high rate of transmission of STEC between dairy animals and wildlife. Overall, the findings improved the understanding of the ecology of the Top 7 STEC in open farm environments, which is required to develop on-farm intervention strategies controlling these zoonoses.


Assuntos
Infecções por Escherichia coli/transmissão , Doenças Transmitidas por Alimentos/microbiologia , Escherichia coli Shiga Toxigênica/isolamento & purificação , Animais , Animais Selvagens/microbiologia , Bovinos , Indústria de Laticínios , Fazendas , Fezes/microbiologia , Tipagem Molecular/métodos , Filogenia , Polimorfismo de Nucleotídeo Único/genética , Escherichia coli Shiga Toxigênica/genética
2.
Lett Appl Microbiol ; 68(2): 112-119, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30411807

RESUMO

Shiga toxin-producing Escherichia coli strains (STEC) are food-borne pathogens. While E. coli O157:H7 is commonly associated with cattle, less is known about the prevalence of non-O157 STEC serogroups in bovines. This study evaluated the prevalence and virulence status of O157:H7 and six E. coli O-serogroups (O26, O103, O45, O145, O121, O111) in New Zealand dairy farms using molecular as well as culture-based methods. Fresh farm dairy effluent (FDE) (n = 36) and composite calf faeces (n = 12) were collected over three samplings from 12 dairy farms. All seven target serogroups were detected through molecular techniques. Of the 202 isolates which were serologically confirmed following traditional culturing and immunomagnetic separation (IMS), O103, O26, O45 and O121 were the most common serogroups, being found in 81, 47, 42 and 32% of the FDE and in 17, 33, 25 and 9% of the calf faeces respectively. The majority (157/202) of the isolates were negative for stx and eae virulence genes. The prevalence of the seven target STEC was low, and only nine O26 isolates (4%) were recovered from four of the farms. The study has highlighted the need for improving the isolation of Top 7 STEC from the stx-negative populations present in fresh dairy effluent and calf faeces. SIGNIFICANCE AND IMPACT OF THE STUDY: Shiga toxin-producing Escherichia coli (STEC) are important food-borne pathogens that can cause severe illness in humans. Cattle are asymptomatic reservoirs for STEC, and transmission to humans can be by consumption of food products or water contaminated with cattle faeces. Our study investigated the prevalence of O157:H7 and six E. coli serogroups of STEC (O26, O103, O45, O145, O121, O111) over time in the dairy reservoir and increases the knowledge and understanding of these pathogens on pasture-based farms. Such information is required to develop risk-assessment models aiming at limiting transmission of these STEC to human.


Assuntos
Adesinas Bacterianas/genética , Infecções por Escherichia coli/veterinária , Escherichia coli O157/isolamento & purificação , Escherichia coli O157/patogenicidade , Proteínas de Escherichia coli/genética , Toxina Shiga/genética , Animais , Bovinos , Indústria de Laticínios , Escherichia coli O157/classificação , Fazendas , Fezes/microbiologia , Doenças Transmitidas por Alimentos/microbiologia , Humanos , Separação Imunomagnética , Nova Zelândia , Prevalência , Sorogrupo , Virulência
3.
J Dairy Sci ; 100(3): 2148-2156, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28109608

RESUMO

The objective of this study was to compare the health, physiology, and behavior of group-housed calves reared on wood shavings with those reared on alternative surfaces. At 1 wk of age, 80 calves were moved into 1 of 20 experimental pens (n = 4 calves/pen) where they remained until 6 wk of age. Pens had floors covered with pea gravel (PG), rubber chip (RC), sand (SA), or wood shavings (WS; n = 5 pens/substrate). Body weight, cleanliness, health, and skin surface and vaginal temperature were recorded at 1, 3, and 6 wk of age. Escherichia coli numbers were assessed on the skin surface of the shoulder and in the feces of calves at 3 and 6 wk of age. Blood samples were taken at 1, 3, and 6 wk of age to measure hematological values and cortisol, IgG, and lactate concentrations. Behaviors (lying, running, and self-grooming) were recorded in the home pen at 1, 3, and 6 wk of age using video recorders and accelerometer data loggers. At 6 wk of age, calves were tested individually in an arena test and behavior was recorded continuously for 20 min. Body weight did not differ among calves reared on PG, RC, SA, or WS, regardless of age. All calves were clean and no calves displayed any signs of lameness, leg lesions, or injuries at wk 1, 3, or 6, regardless of substrate. The number of E. coli recovered from a surface area of 100 cm2 on the shoulder of each calf was affected by rearing substrate, with more E. coli recovered from calves reared on WS than PG, RC, or SA at 3 and 6 wk of age. Fecal E. coli counts were not affected by rearing substrate at 3 or 6 wk of age. Over the entire study period, calves reared on PG and SA had lower skin temperatures than calves reared on RC or WS, but skin temperature was similar between calves reared on PG and SA. However, vaginal temperature did not differ among calves reared on different substrates at 1, 3, or 6 wk of age. Hematology values and cortisol, IgG, and lactate concentrations of calves were similar among rearing substrates over the 6-wk study period. In the home pen, rearing substrate did not influence time spent lying; however, calves reared on WS performed more lying bouts than calves reared on PG or SA. In addition, rearing substrate did not influence the time calves spent running; however, calves reared on WS spent more time self-grooming than calves reared on PG, RC, and SA. During a 20-min arena test, running, bucks, jumps, and kicks performed by calves was not affected by rearing substrate. In conclusion, the physiology and behavior of calves reared on PG, RC, and SA was similar to WS, which is considered the preferred rearing substrate to use when rearing calves. Therefore, PG, RC, and SA may be acceptable substrate options when rearing group-housed dairy calves.


Assuntos
Escherichia coli , Abrigo para Animais , Animais , Comportamento Animal , Peso Corporal , Bovinos , Comportamento Social
4.
J Appl Microbiol ; 116(4): 1035-43, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24372778

RESUMO

AIM: To determine the faecal excretion of Campylobacter jejuni by dairy cows that used housing in combination with outdoor grazing. METHODS AND RESULTS: Campylobacter jejuni prevalence and concentration were measured in a total of 990 cow faecal samples collected from seven herd home farms (HH), seven stand-off pad farms (SOP) and seven pasture farms (P) over a 2-year period. On all the farms, cows had access to pasture but were restricted to narrow grazing strips in winter. The overall Camp. jejuni prevalence was 55, 49 and 54% on HH, SOP and P farms, respectively. The Camp. jejuni concentration ranged from 0 to 6·7 log10 g(-1) faeces and was not statistically different among the farm systems. However, Camp. jejuni prevalence (P = 0·014) and concentration (P = 0·0001) were significantly greater in winter and early spring after intensive use of HH, SOP and strip-grazing. Typing of 30 Camp. jejuni isolates revealed a dominance of ruminant types (MLST CC-61, CC-21, CC-42 and CC-48), which are associated with human disease. CONCLUSION: No overall difference was observed among systems, but seasonal management practices that force cows close together increased the prevalence and concentration of Camp. jejuni in faeces. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings are important when identifying farm practices that reduce Camp. jejuni excretion and the associated risk to human health.


Assuntos
Campylobacter jejuni/isolamento & purificação , Bovinos/microbiologia , Indústria de Laticínios , Animais , Campylobacter jejuni/genética , Fezes/microbiologia , Feminino , Genótipo , Abrigo para Animais
6.
J Appl Microbiol ; 108(5): 1485-93, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19912432

RESUMO

There is an increasing interest in the detection and enumeration of micro-organisms pathogenic for human and present in bovine faeces. This interest is because pollution of the environment by animal faeces may affect the safety of food and of drinking or recreational water. Detection and quantification of microbial pathogens carried out using DNA extracted from the faecal matrix are affected by the quality and the quantity of the DNA extracts, which are critical factors that limit the accuracy and sensitivity of molecular studies. This review compares published methods on DNA extraction from bovine faeces, focusing on the extent to which the success of DNA amplification is affected by issues related to the faeces. Following a general discussion on the DNA extraction methods used for faeces, we focus particularly on issues related to the faecal environment itself. The objective is to identify information that can be used to improve the sensitivity of those PCR methods used after direct DNA extraction.


Assuntos
DNA Bacteriano/isolamento & purificação , Fezes/microbiologia , Técnicas Genéticas , Animais , Bovinos , DNA Bacteriano/genética , Técnicas Genéticas/tendências , Reação em Cadeia da Polimerase
7.
Minerva Urol Nefrol ; 60(2): 93-103, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18500224

RESUMO

In the last decade we have seen the emergence of botulinum toxin (BTX) as a successful treatment of patients with neurogenic and idiopathic detrusor overactivity that are refractory to antimuscarinic medication. The success of BTX in this patient population has led to use BTX in patients with other causes of lower urinary tract symptoms such as benign prostatic hyperplasia (BPH) and urethral sphincter anomalies. Despite this success, the protocol for BTX injection has not yet been standardized. Various studies are on the way in order to determine the best injection protocol for bladder injection of BTX. The use of BTX in patients with BPH is in its early stages. Further large randomized controls trials in patients with BPH are needed to determine the efficacy of BTX in this patient population.


Assuntos
Toxinas Botulínicas/uso terapêutico , Prostatismo/tratamento farmacológico , Administração Intravesical , Toxinas Botulínicas/administração & dosagem , Humanos , Masculino , Bexiga Urinária Hiperativa/tratamento farmacológico
8.
NPJ Prim Care Respir Med ; 27(1): 28, 2017 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-28432297

RESUMO

Clinical experience has shown that allergic and non-allergic respiratory, metabolic, mental, and cardiovascular disorders sometimes coexist with bronchial asthma. However, no study has been carried out that calculates the chance of manifestation of these disorders with bronchial asthma in Saarland and Rhineland-Palatinate, Germany. Using ICD10 diagnoses from health care institutions, the present study systematically analyzed the co-prevalence and odds ratios of comorbidities in the asthma population in Germany. The odds ratios were adjusted for age and sex for all comorbidities for patients with asthma vs. without asthma. Bronchial asthma was strongly associated with allergic and with a lesser extent to non-allergic comorbidities: OR 7.02 (95%CI:6.83-7.22) for allergic rhinitis; OR 4.98 (95%CI:4.67-5.32) allergic conjunctivitis; OR 2.41 (95%CI:2.33-2.52) atopic dermatitis; OR 2.47 (95%CI:2.16-2.82) food allergy, and OR 1.69 (95%CI:1.61-1.78) drug allergy. Interestingly, increased ORs were found for respiratory diseases: 2.06 (95%CI:1.64-2.58) vocal dysfunction; 1.83 (95%CI:1.74-1.92) pneumonia; 1.78 (95%CI:1.73-1.84) sinusitis; 1.71 (95%CI:1.65-1.78) rhinopharyngitis; 2.55 (95%CI:2.03-3.19) obstructive sleep apnea; 1.42 (95%CI:1.25-1.61) pulmonary embolism, and 3.75 (95%CI:1.64-8.53) bronchopulmonary aspergillosis. Asthmatics also suffer from psychiatric, metabolic, cardiac or other comorbidities. Myocardial infarction (OR 0.86, 95%CI:0.79-0.94) did not coexist with asthma. Based on the calculated chances of manifestation for these comorbidities, especially allergic and respiratory, to a lesser extent also metabolic, cardiovascular, and mental disorders should be taken into consideration in the diagnostic and treatment strategy of bronchial asthma. BRONCHIAL ASTHMA: PREVALENCE OF CO-EXISTING DISEASES IN GERMANY: Patients in Germany with bronchial asthma are highly likely to suffer from co-existing diseases and their treatments should reflect this. Quoc Thai Dinh at Saarland University Hospital in Homburg, Germany, and co-workers conducted a large-scale study of patients presenting with bronchial asthma in the Saarland region between 2009 and 2012. Patients with asthma made up 5.4% of the region's total population, with a higher prevalence occurring in females. They found that bronchial asthma was strongly associated with allergic comorbidities such as rhinitis. Indeed, asthmatic patients had a seven times higher chance to suffer from allergic rhinitis than the rest of the population, and were at higher risk of respiratory diseases like pneumonia and obstructive sleep apnea syndrome. Further associations included cardiovascular, metabolic and mental disorders. Dinh's team call for asthma treatments to take such comorbidities into account.


Assuntos
Asma/epidemiologia , Cardiopatias/epidemiologia , Hipersensibilidade/epidemiologia , Transtornos Mentais/epidemiologia , Doenças Metabólicas/epidemiologia , Doenças Respiratórias/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Comorbidade , Conjuntivite Alérgica/epidemiologia , Estudos Transversais , Bases de Dados Factuais , Dermatite Atópica/epidemiologia , Hipersensibilidade a Drogas/epidemiologia , Feminino , Hipersensibilidade Alimentar/epidemiologia , Alemanha/epidemiologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Nasofaringite/epidemiologia , Razão de Chances , Pneumonia/epidemiologia , Aspergilose Pulmonar/epidemiologia , Embolia Pulmonar/epidemiologia , Rinite Alérgica/epidemiologia , Sinusite/epidemiologia , Apneia Obstrutiva do Sono/epidemiologia , Disfunção da Prega Vocal/epidemiologia , Adulto Jovem
9.
Water Sci Technol ; 54(6-7): 477-84, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17120683

RESUMO

Highway runoff can cause a number of water quantity and quality problems. Stormwater management systems for highways have been developed based on a fast drainage for large storm situations. Non-point source pollution from highway runoff is a growing water quality concern. Stormwater quality control needs to be integrated into highway drainage design and operation to reduce the stormwater impacts on the receiving water. A continuous simulation/optimisation model for analysing integrated highway best management practices (BMPs) is presented. This model can evaluate the life cycle performance of infiltration and/or storage oriented highway BMPs. It can be directly integrated with spreadsheet optimisation tools to find the least cost options for implementing BMPs throughout a specified life cycle.


Assuntos
Drenagem Sanitária , Chuva , Movimentos da Água , Abastecimento de Água , Benchmarking , Cidades , Simulação por Computador , Veículos Automotores
10.
Water Sci Technol ; 51(10): 291-300, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16104433

RESUMO

The 'H2S test' is being advanced for microbiological water quality testing where conventional coliform based methods are impractical or too expensive. It involves ambient temperature incubation of water samples with nutrient formulated to generate hydrogen sulphide when 'faecal' bacteria are present. Recently a WHO review identified several concerns including the limited number of comparative studies, formulation variability, and false positives and negatives. In response we have compared the H2S test's ability to detect and quantify faecal contamination in an aquifer impacted by septic tank leachfields with measurements obtained concurrently using conventional bacterial indicators, coliphages, faecal sterol biomarkers, Cryptosporidium and Giardia. Like these other analytes, H2S testing detected a contamination gradient ranging from high (septic liquid) to moderate (exfiltration zones), to background (e.g. domestic bores), corresponding to indicator removal + dilution by factors > 10(6). Presence/absence tests could not distinguish between heavily and slightly contaminated waters, whereas multi-tube testing (e.g. 10 x 10 mL arrays) did. It was concluded that while the WHO review concerns are justified, the H2S test performance shows promise in sanitary survey work, can be improved by employing an mpn approach and has potential to aid in the protection of source water and identifying contaminated groundwater.


Assuntos
Fezes , Sulfeto de Hidrogênio/análise , Esgotos , Monitoramento Ambiental , Filtração , Saneamento , Sensibilidade e Especificidade , Poluentes do Solo/análise , Microbiologia da Água , Poluentes da Água/análise
11.
Psychopharmacology (Berl) ; 51(1): 91-100, 1976 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-827781

RESUMO

The effects of d-amphetamine on temporal discrimination in the rat were studied. Rats were trained on a two-manipulandum task involving the discrimination between two tones differing only in duration. d-Amphetamine (0.1 - 1.6 mg/kg) disrupted performance on this task, although not in an obvious dose-related manner. Lever biases were enhanced by the drug, but inconsistenly among rats. Enhanced lever bias did not necessarily correlate with deterioration of performance. The drug lengthened both response latency and the performance of terminal components of the operant chain. However the characteristic pattern of response latencies produced by the two tones was not altered significantly by the drug. The results are discussed in terms of whether the drug disrupts discrimination performance by a direct effect on processes of temporal discrimination or indirectly, by its other effects on behavior.


Assuntos
Dextroanfetamina/farmacologia , Percepção do Tempo/efeitos dos fármacos , Animais , Condicionamento Operante/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Ratos , Tempo de Reação/efeitos dos fármacos
12.
Brain Res ; 872(1-2): 262-5, 2000 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-10924706

RESUMO

The enriched environment (EC) causes morphological plasticity in striatal cells that express D1 and D2 receptors. We used radioligand binding assays to examine whether EC produces plasticity in striatal receptor density and receptor density ratios. After 30 days of EC, 2-year-old rats had a higher ratio of D1 to muscarinic receptors in striatum relative to singly housed rats. Assays also showed trends for a greater ratio of D1 to cannabinoid receptors and a greater density of D1 receptors in striatum after EC. D2 receptor density was unaffected by the EC condition.


Assuntos
Envelhecimento/metabolismo , Corpo Estriado/metabolismo , Meio Ambiente , Receptores de Dopamina D1/metabolismo , Receptores Muscarínicos/metabolismo , Análise de Variância , Animais , Química Encefálica/fisiologia , Corpo Estriado/química , Masculino , Ensaio Radioligante , Ratos , Ratos Endogâmicos F344 , Receptores de Canabinoides , Receptores de Dopamina D1/análise , Receptores de Dopamina D2/análise , Receptores de Dopamina D2/metabolismo , Receptores de Droga/análise , Receptores de Droga/metabolismo , Receptores Muscarínicos/análise
13.
Physiol Behav ; 70(5): 425-9, 2000 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11110995

RESUMO

Previous studies indicate that the hippocampus is active during exercise, and that neurotrophin expression, receptor density, and survival of dentate gyrus granule cells in the hippocampus can be modified by moderate voluntary exercise. The present study was designed to test the consequences of voluntary exercise on a hippocampal-related behavior. Exercising and control rats were tested on the standard and delayed nonmatch-to-position (DNMTP) version of the eight-arm radial maze, both of which are sensitive to hippocampal damage. Voluntarily exercising rats ran in running wheels attached to their home cage for 7 weeks prior to and throughout testing, and took 30% fewer trials to acquire criterion performance than sedentary controls. Both groups spent the same average time per arm. Once the eight-arm maze had been learned to criterion, group differences were not apparent. Exercise can facilitate acquisition of a hippocampal-related spatial learning task, but does not affect performance following acquisition. Further work will be necessary to link these effects to hippocampal-related variables shown to be influenced by exercise.


Assuntos
Hipocampo/fisiologia , Aprendizagem em Labirinto/fisiologia , Atividade Motora/fisiologia , Percepção Espacial/fisiologia , Análise de Variância , Animais , Feminino , Ratos , Ratos Long-Evans , Tempo de Reação/fisiologia
14.
Ann Clin Lab Sci ; 23(6): 423-32, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8291897

RESUMO

T-cell receptor antibodies (TCR alpha beta and TCR gamma delta) were used for a flow cytometric study of 114 specimens of lymphoid neoplasms and normal controls in order to find out whether or not the expression of TCR proteins differs in between normal and neoplastic tissues. It was found that TCR alpha beta population was predominant in all categories except T gamma lymphoproliferative disorder (TGLD), T-cell lymphoblastic leukemia (T-ALL), and natural killer-like T-cell lymphoma (NKTL), in which three of 18, one of three, and two of two specimens, respectively, showed a predominant TCR gamma delta population. Natural killer cell lymphoma (NKL) showed essentially absence of either TCR alpha beta or TCR gamma delta protein. Therefore, TCR antibodies can be selectively used in cases of TGLD, T-ALL, and NKTL to substantiate their diagnoses. Furthermore, the absence of TCR protein is characteristic of NKL and helps to distinguish it from NKTL. Without the TCR antibodies, TCR gene analysis is sometimes needed to separate these two entities. When comparing with genotyping, 11 of 12 cases with TCR beta gene rearrangement and one of two cases with TCR alpha gene rearrangement expressed TCR alpha beta protein. One of four cases with TCR gamma gene rearrangement and both cases with TCR delta gene rearrangement expressed TCR gamma delta protein. Thus, TCR antibody phenotyping can reliably predict TCR genotypes under most circumstances.


Assuntos
Expressão Gênica , Genótipo , Linfoma/genética , Fenótipo , Receptores de Antígenos de Linfócitos T/genética , Diagnóstico Diferencial , Citometria de Fluxo , Rearranjo Gênico do Linfócito T , Humanos , Imunofenotipagem , Leucemia/diagnóstico , Leucemia/genética , Leucemia/imunologia , Leucemia Linfocítica Crônica de Células B/genética , Leucemia-Linfoma de Células T do Adulto/genética , Linfoma/diagnóstico , Linfoma/imunologia , Linfoma de Células B/genética , Linfoma de Células T/genética
15.
Acta Astronaut ; 39(1-4): 229-38, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-11540763

RESUMO

The Suess-Urey (S-U) mission has been proposed as a NASA Discovery mission to return samples of matter from the Sun to the Earth for isotopic and chemical analyses in terrestrial laboratories to provide a major improvement in our knowledge of the average chemical and isotopic composition of the solar system. The S-U spacecraft and sample return capsule will be placed in a halo orbit around the L1 Sun-Earth libration point for two years to collect solar wind ions which implant into large passive collectors made of ultra-pure materials. Constant Spacecraft-Sun-Earth geometries enable simple spin stabilized attitude control, simple passive thermal control, and a fixed medium gain antenna. Low data requirements and the safety of a Sun-pointed spinner, result in extremely low mission operations costs.


Assuntos
Astronomia/instrumentação , Meio Ambiente Extraterreno , Sistema Solar , Voo Espacial/instrumentação , Astronave/instrumentação , Contenção de Riscos Biológicos , Elementos Químicos , Desenho de Equipamento , Isótopos , Monitoramento de Radiação/instrumentação , Projetos de Pesquisa , Telecomunicações
16.
J Anim Sci ; 90(1): 27-36, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21873535

RESUMO

Two selection methods, 1-stage selection (OSS) and 2-stage selection (TSS), for improving efficiency and profitability of selective breeding of yellow perch were evaluated, through examining the genetic and phenotypic parameters for BW of F(1) fish using microsatellite parentage assignment in this study. Approximately 94% of the sampled yellow perch progeny were assigned to single parental pairs using 8 microsatellite markers, which confirmed the applicability of the communal rearing technique in yellow perch breeding. Within OSS, the genetic correlation between 1-yr-BW and 2-yr-BW was high (0.98), indicating that the growth of yellow perch recorded at yr 1 could predict their growth for yr 2. Also mean family BW and family EBV for BW between yr 1 and 2 were found to be significantly correlated, suggesting yr 1 fast-growing yellow perch families continued to be the fast growing families in yr 2. Two-year random fish undergoing TSS were significantly heavier (P < 0.01) than those undergoing OSS. In addition, top males and females with TSS were heavier (P < 0.01) than those with OSS. Based on these results we concluded that the TSS was more desirable and effective for yellow perch breeding compared with OSS in terms of improving selection efficiency and reducing costs.


Assuntos
Aquicultura/métodos , Repetições de Microssatélites , Percas/genética , Seleção Genética , Animais , Aquicultura/economia , Tamanho Corporal , Cruzamento/economia , Cruzamento/métodos , Feminino , Genótipo , Masculino , Ohio , Linhagem , Percas/crescimento & desenvolvimento , Percas/fisiologia , Fenótipo , Reprodução
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