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1.
Animal ; 12(9): 1799-1806, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29191252

RESUMO

Until recently, the main selection focus in UK dairy goats has been on milk yield. To develop a selection index suitably weighted for a variety of traits, it is important to understand the genetic relationships between production, health and fertility traits. This study focussed on three aspects of reproduction that are of interest to goat breeders. (1) Out of season (OOS) kidding ability: goats are highly seasonal breeders so achieving consistent, year-round dairy production presents a challenge. It may be possible to select for extended or shifted breeding cycles, however, there are no published studies on the genetic basis of seasonal kidding ability, and a genetic correlation with milk production in dairy goats; (2) age at first kidding (AFK): a reduced AFK offers the opportunity for more rapid genetic improvement, as well as reducing the amount of time and resources required to raise the animals to producing age; (3) pseudopregnancy (PPG): as it is difficult to diagnose pregnancy within 30 days of mating, high herd levels of PPG could add a significant delay in breeding replacement animals, or commencing a new lactation. Using records from 9546 goats, the objective of this study was to investigate the genetic relationships between the reproductive traits described above, and the production traits 520-day milk yield (MY520), lifetime milk yield (MYLife) and lifetime number of days in milk (DIMLife). The 'out of season' phenotype was defined as week of kidding relative to the 4 weeks of the year where the highest average number of births occur. Incidences of PPG that occurred during the first lactation were used as cases, while goats with none were assigned as controls. Relevant fixed and random effects were fitted in the models. In line with other reproduction traits, heritability estimates were low ranging from 0.08 to 0.11. A negative genetic correlation was found between AFK and MY520 (-0.22±0.10), whereas a positive genetic correlation was found between PPG and DIMLife (0.58±0.11). Pseudopregnancy and OOS were positively genetically correlated (0.36±0.15). All other genetic correlations were very low. The results of this study indicate that selection for the reproductive traits analysed is feasible, without adversely affecting MYLife.


Assuntos
Cruzamento , Cabras , Pseudogravidez , Animais , Indústria de Laticínios , Feminino , Fertilidade , Cabras/genética , Cabras/fisiologia , Lactação , Leite , Fenótipo , Gravidez
2.
Animal ; 10(8): 1243-53, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26857289

RESUMO

Aggression at regrouping is a common issue in pig farming. Skin lesions are genetically and phenotypically correlated with aggression and have been shown to have a significant heritable component. This study predicts the magnitude of reduction in complex aggressive behavioural traits when using lesion numbers on different body regions at two different time points as selection criteria, to identify the optimum skin lesion trait for selection purposes. In total, 1146 pigs were mixed into new social groups, and skin lesions were counted 24 h (SL24h) and 3 weeks (SL3wk) post-mixing, on the anterior, centre and posterior regions of the body. An animal model was used to estimate genetic parameters for skin lesion traits and 14 aggressive behavioural traits. Estimated breeding values (EBVs) and phenotypic values were scaled and standardised to allow direct comparison across multiple traits. Individuals with SL24h and SL3wk EBVs in the least aggressive 10% of the population were compared with the population mean to predict the expected genetic and phenotypic response in aggressive behaviour to selection. At mixing, selection for low anterior lesions was predicted to affect substantially more behavioural traits of aggressiveness than lesions obtained on other body parts, with EBVs between -0.21 and -1.17 SD below the population mean. Individuals with low central SL24h EBVs also had low EBVs for aggressive traits (-0.33 to -0.55). Individuals with high SL3wk EBVs had low EBVs for aggression at mixing (between -0.24 and -0.53 SD below the population mean), although this was predicted to affect fewer traits than selection against SL24h. These results suggest that selection against anterior SL24h would result in the greatest genetic and phenotypic reduction in aggressive behaviour recorded at mixing. Selection for increased SL3wk was predicted to reduce aggression at mixing; however, current understanding about aggressive behaviour under stable social conditions is insufficient to recommend using this trait for selection purposes.


Assuntos
Agressão , Pele/lesões , Sus scrofa/fisiologia , Animais , Cruzamento , Feminino , Masculino , Sus scrofa/genética
3.
J Anim Sci ; 93(7): 3303-12, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26439999

RESUMO

The objective of this study was to investigate the genetic relationships between skin lesion traits in group housed growing pigs as a measure of short- (in a newly mixed group) and long- (in a socially stable group) term aggression and commonly used commercial performance measures: growth, feed intake, feed efficiency, and carcass traits. Data on 2,413 growing pigs (138 groups) were available. Pigs were mixed into new social groups of 18 animals, and skin lesions were counted 24 h (SL24h) and 5 wk (SL5wk) postmixing. The animal model was used to estimate genetic parameters for skin lesion traits, test daily gain, lifetime daily gain, daily feed intake, feed efficiency (calculated as test daily gain divided by daily feed intake), loin depth, back fat, and HCW. Skin lesions had a heritable component, ranging from 0.08 for anterior SL24h to 0.22 for central SL5wk and would, therefore, be suitable as a method of phenotyping aggression for selection purposes. Significant positive genetic correlations were found between SL24h and SL5wk (0.46 to 0.81). Positive genetic correlations were also found between SL24h (central and posterior body regions) or SL5wk (all body regions) and the production traits lifetime daily gain, test daily gain, and HCW (0.29 to 0.54). Central SL24h, anterior SL5wk, and posterior SL5wk were found to correlate positively with feed efficiency (0.39 to 0.50), suggesting that pigs with more lesions convert feed more efficiently. Where significant, the magnitude of phenotypic correlations was low but positive (0.07 to 0.10). These results suggest that, genetically, animals that receive many lesions show improved performance compared to those with few lesions, except for anterior SL24h, which had previously been shown to be genetically positively correlated with the initiation of nonreciprocal attacks. It may, therefore, be possible, via selection against anterior skin lesions at mixing, to reduce this form of 1-sided aggression without adversely affecting production traits.


Assuntos
Agressão/fisiologia , Comportamento Animal/fisiologia , Doenças dos Suínos/patologia , Aumento de Peso/genética , Ferimentos e Lesões/veterinária , Envelhecimento , Animais , Composição Corporal/genética , Composição Corporal/fisiologia , Suínos
4.
J Black Psychol ; 41(6): 540-564, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26778866

RESUMO

The current study examined body image concerns among African American women. In recent years, there has been an attempt to include ethnic minority samples in body image studies (e.g., Grabe & Hyde, 2006; Hrabosky & Grilo, 2007; Lovejoy, 2001) but few specifically examine unique issues pertaining to beauty and body image for African American college age women. A total of 31 African American women participated in one of five focus groups on the campus of a large Southwestern University to examine beauty and body image. Data were analyzed using a thematic approach and several themes were identified. The majority of themes pertained to issues related to hair, skin tone, body type, and message sources. Themes included: sacrifice, ignorance/racial microaggressions, and validation and invalidation by others, thick/toned/curvy as optimal, hypersexualization, and being thin is for White women. Findings of the current study suggest a reconceptualization of body image for African American women where relevant characteristics such as hair and skin tone are given more priority over traditional body image concerns often associated with European American women.

5.
Bone Marrow Transplant ; 47(9): 1178-85, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22231460

RESUMO

CY in combination with BU is a widely used conditioning regimen for haematopoietic SCT (HSCT). The aim of this study was to evaluate the pharmacokinetics (PK) of CY and its major metabolite 4-hydroxyCY (HCY) in patients with thalassemia undergoing HSCT. A total of 55 patients received BU (16 mg/kg) followed by CY (160-200 mg/kg) both over 4 days before HSCT. A population PK model was developed to describe the disposition of CY and HCY and the inter-individual (IIV) and inter-occasion variability (IOV). The model was also used to determine the effects covariates including: demographics, Lucarelli classification and polymorphisms in enzymes involved in the metabolism or biotransformation of CY had on CY and HCY disposition. Overall, 17-114% IIV and 12-103% IOV in CY and HCY PK parameters were observed. Body weight and age were the main covariates, which explained the largest portion of the IIV. In addition, CYP2C9*2 explained a significant portion of the IIV in the clearance (P<0.002) and thus the area under the concentration curve (P<0.05) of CY. This covariate model may be used to design and plan targeted dose therapy in this group of pediatric patients, if clinical outcome association with CY PK are proved and target range established.


Assuntos
Ciclofosfamida/farmacocinética , Transplante de Células-Tronco Hematopoéticas/métodos , Condicionamento Pré-Transplante/métodos , Talassemia beta/metabolismo , Talassemia beta/terapia , Adolescente , Criança , Pré-Escolar , Ciclofosfamida/administração & dosagem , Feminino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Masculino , Talassemia beta/tratamento farmacológico , Talassemia beta/cirurgia
7.
Rev Neurol (Paris) ; 151(1): 63-6, 1995 Jan.
Artigo em Francês | MEDLINE | ID: mdl-7676134

RESUMO

We report the case of a 64 year old woman treated for 10 years by DOPA for Parkinson's disease and displaying brown urine. Homogentisic acid was found in urine, establishing the diagnosis of alkaptonuria. Clinical and radiological studies demonstrated ochronosis and ochronotic arthropathy, blue pigmentation of ear cartilage and calcification of the intervertebral lumbar disc giving the classical "inverted spine". Interrelation between this metabolic abnormality and Parkinson's disease is discussed. The recent cloning and mapping of the human gene for alkaptonuria to chromosome 3q should bring some clarification among relationships between these two diseases.


Assuntos
Alcaptonúria/etiologia , Ocronose/etiologia , Doença de Parkinson/complicações , Alcaptonúria/diagnóstico , Antiparkinsonianos/uso terapêutico , Diagnóstico Diferencial , Feminino , Humanos , Levodopa/metabolismo , Levodopa/uso terapêutico , Pessoa de Meia-Idade , Ocronose/diagnóstico , Doença de Parkinson/tratamento farmacológico
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