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1.
J Reprod Immunol ; 163: 104214, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38508038

RESUMO

Although several testicular alterations promoted by coronavirus infection have been demonstrated, the extent, causes, and players of testicular pathogenesis are not totally understood. The present study aimed to investigate the short-term effects on male fertility of intranasally administered murine hepatitis virus strain 3 (MHV-3), a member of the genus Betacoronavirus, which causes a severe systemic acute infection. This mouse model might be used as a in vivo prototype for investigating the impact of betacoronavirus on the endocrine and exocrine testicular functions with the advantage to be performed in a biosafety level 2 condition. Herein, we performed virological, histopathological, and molecular studies regarding the testicular spermatogenesis and the spermatic quality analyses in an MHV-3-infected C57BL/6 mice. The main outcomes showed that MHV-3 infects mouse testis and induces a testicular inflammatory state, impairing the steroidogenic pathway. The infection led to several alterations in the testicular parenchyma, such as: seminiferous epithelium sloughing, retention of residual bodies, germ cell apoptosis, alterations in intercellular junction proteins, and worse spermatogenic parameters. Moreover, the levels of plasmatic testosterone as well as the quality of sperm production reduced. Therefore, the present data suggest that the viral/inflammatory impairment of the steroidogenic pathway and the consequent imbalance of androgen levels is critical in testicular pathology, disturbing the SC barrier function and the germ cell differentiation. Our study is important for comprehending the effects of beta coronavirus infections on testis function in order to develop treatments that could prevent virus-mediated male infertility.


Assuntos
Camundongos Endogâmicos C57BL , Vírus da Hepatite Murina , Espermatogênese , Espermatozoides , Testículo , Animais , Masculino , Camundongos , Testículo/virologia , Testículo/patologia , Testículo/imunologia , Espermatozoides/virologia , Espermatozoides/imunologia , Espermatozoides/patologia , Modelos Animais de Doenças , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Infecções por Coronavirus/imunologia , Infertilidade Masculina/virologia , Infertilidade Masculina/imunologia , Infertilidade Masculina/patologia , Infertilidade Masculina/etiologia , Testosterona/sangue , Humanos
2.
Trop Anim Health Prod ; 54(1): 34, 2022 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-34978613

RESUMO

The objective of this study was to contribute to genetic improvement for carcass quality in Nellore cattle by estimating genetic parameters for carcass characteristics measured by traditional and novel ultrasound adjusted for body weight. Records of 19,910 Nellore breed animals born between 2001 and 2015 as part of a genetic improvement program were evaluated for this purpose. The (co)variance components and genetic parameters for yearling weight (YW), slaughter conformation at yearling age (SCY), ribeye area (REA), REA adjusted for 100 kg of body weight (REA100), REA adjusted for 450 kg of body weight (REA450), subcutaneous fat thickness over the loin (SFTL) and the rump (SFTR), intramuscular fat (IF), and height × width ratio of the sirloin steak (RATIO) were estimated using the restricted maximum likelihood (REML) method and the three-trait animal model. The estimated heritability values were 0.39 (YW), 0.33 (SCY), 0.31 (REA), 0.42 (REA100), 0.38 (REA450), 0.31 (RATIO), 0.17 (SFTL), 0.27 (SFTR), and 0.41 (MAR). The genetic correlations between REA and YW (0.43) and SCY and YW (0.78), respectively, suggested that selecting for REA or SCY could result in an increase in body weight. Because of its moderate and negative correlation with YW, REA100 was ineffective as a muscling indicator (- 0.38). The indicators REA450 and RATIO had a - 0.12 and 0.11 low correlation with YW, respectively. Thus, it is concluded that REA450 and RATIO were the best indicators of muscling, with heritability of medium magnitude, making the selection viable, as well as having a low correlation with body weight.


Assuntos
Modelos Genéticos , Músculos , Animais , Peso Corporal , Bovinos/genética , Fenótipo , Ultrassonografia/veterinária
3.
Cell Tissue Res ; 386(1): 173-190, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34296344

RESUMO

The monocyte chemoattractant protein 1 (MCP-1) belongs to the CC chemokine family and acts in the recruitment of C-C motif chemokine receptor 2 (CCR2)-positive immune cell types to inflammation sites. In testis, the MCP-1/CCR2 axis has been associated with the macrophage population's functional regulation, which presents significant functions supporting germ cell development. In this context, herein, we aimed to investigate the role of the chemokine receptor CCR2 in mice testicular environment and its impact on male sperm production. Using adult transgenic mice strain that had the CCR2 gene replaced by a red fluorescent protein gene, we showed a stage-dependent expression of CCR2 in type B spermatogonia and early primary spermatocytes. Several parameters related to sperm production were reduced in the absence of CCR2 protein, such as Sertoli cell efficiency, meiotic index, and overall yield of spermatogenesis. Daily sperm production decreased by almost 40%, and several damages in the seminiferous tubules were observed. Significant reduction in the expression of important genes related to the Sertoli cell function (Cnx43, Vim, Ocln, Spna2) and meiosis initiation (Stra8, Pcna, Prdm9, Msh5) occurred in comparison to controls. Also, the number of macrophages significantly decreased in the absence of CCR2 protein, along with a disturbance in Leydig cell steroidogenic activity. In summary, our results show that the non-activation of the MCP-1/CCR2 axis disturbs the testicular homeostasis, interfering in macrophage population, meiosis initiation, blood-testis barrier function, and androgen synthesis, leading to the malfunction of seminiferous tubules, decreased testosterone levels, defective sperm production, and lower fertility index.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Macrófagos/metabolismo , Receptores de Quimiocinas/metabolismo , Espermatogênese/fisiologia , Testículo/fisiologia , Animais , Feminino , Humanos , Masculino , Camundongos
5.
Animal ; 15(3): 100160, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33546982

RESUMO

Improving feed efficiency is a key breeding goal in the beef cattle industry. In this study, we estimated the genetic parameters for feed efficiency and carcass traits in Senepol cattle raised in tropical regions. Various indicators of feed efficiency [gain to feed ratio (G:F), feed conversion ratio (FCR), residual weight gain (RG), residual intake and body weight gain (RIG), and residual feed intake (RFI)] as well as growth [final BW, average daily gain (ADG), and DM intake (DMI)], and carcass [rib-eye area (REA), backfat thickness (BF), intramuscular fat score, and carcass conformation score] traits were included in the study. After data editing, records from 1 393 heifers obtained between 2009 and 2018 were used for the analyses. We fitted an animal model that included contemporary group (animals from the same farm that were evaluated in the same test season) as the fixed effect, and a linear effect of animal age at the beginning of the test as a covariate; in addition to random direct additive genetic and residual effects. The (co)variance components were estimated by Bayesian inference in uni- and bivariate analyses. Our results showed that feed efficiency indicators derived from residual variables such as RG, RIG, and RFI can be improved through genetic selection (h2 = 0.14 ± 0.06, 0.13 ± 0.06, and 0.20 ± 0.08, respectively). Variables calculated as ratios such as G:F and FCR were more influenced by environmental factors (h2 = 0.08 ± 0.05 and 0.09 ± 0.05), and were, therefore, less suitable for use in breeding programs. The traits with the greatest and impact on genetic progress in feed efficiency were ADG, REA, and BF. The traits with the greatest and least impact on growth and carcass traits were RG and RFI, respectively. Selection for feed efficiency will result in distinct overall effects on the growth and carcass traits of Senepol heifers. Direct selection for lower RFI may reduce DMI and increase carcass fatness at the finishing stage, but it might also result in reduced growth and muscle deposition. Residual BW gain is associated with the highest weight gain and zero impact on REA and BF, however, it is linked to higher feed consumption. Thus, the most suitable feed efficiency indicator was RIG, as it promoted the greatest decrease in feed intake concomitant with faster growth, with a similar impact on carcass traits when compared to the other feed efficiency indicators.


Assuntos
Ingestão de Alimentos , Aumento de Peso , Ração Animal , Animais , Teorema de Bayes , Bovinos/genética , Feminino , Fenótipo
6.
Animal ; 15(3): 100142, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33573956

RESUMO

Growing concerns regarding sustainability in agriculture include the availability of drinking water, which is putting pressure on livestock production, especially the beef sector, for more efficient practices. Thus, genetic parameters were estimated for traits related to water intake and water use efficiency in Senepol cattle. Senepol females (n = 925) and males (n = 191) were evaluated in performance tests carried out from 2014 to 2019. Daily dry matter intake (DMI) and water intake (WI) were recorded by electronic feed and water bunks (Intergado Ltd.). Other traits assessed included average daily gain (ADG); mid-test metabolic BW (BW0.75); residual water intake based on ADG (RWIADG), estimated as the residual of the linear regression equation of WI on ADG and BW0.75; residual water intake based on DMI (RWIDMI), estimated as the residual of the linear regression equation of WI on DMI and BW0.75 (RWIDMI); water conversion ratio (= WI/ADG); gross water efficiency (GWE = ADG/WI); residual feed intake estimated as the residual of the linear regression equation of DMI on ADG and BW0.75 (RFI); feed conversion ratio (= DMI/ADG) and gross feed efficiency. Genetic (co)variances were estimated with bivariate analyses. The heritabilities for WI, RWIADG and RWIDMI were 0.38, 0.36 and 0.33, respectively. Water conversion ratio, RWIADG and RWIDMI showed positive genetic and phenotypic correlations with WI, whereas GWE was negatively correlated with WI, suggesting that traits related to water use efficiency may be useful to identify cattle with reduced WI. Water intake showed positive genetic (r = 0.79) and phenotypic (r = 0.60) correlations with DMI, suggesting the use of WI to estimate DMI in future studies. Both RWIADG and RWIDMI were genetically correlated with RFI (0.67 and 0.57, respectively) and ADG (0.49 and 0.44, respectively), showing that RWI is positively associated with feed efficiency, but has an antagonistic relationship with growth. This antagonism, however, may be managed using selection indexes. Genetic improvement of water use efficiency in Senepol cattle is possible through selection and may reduce the water requirements of beef production systems.


Assuntos
Ingestão de Líquidos , Ingestão de Alimentos , Ração Animal , Animais , Bovinos/genética , Feminino , Masculino , Fenótipo , Seleção Genética , Água
7.
Arq. bras. med. vet. zootec. (Online) ; 71(6): 1889-1895, Nov.-Dec. 2019. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-1055129

RESUMO

A utilização da gema de ovo dificulta a padronização de meios diluidores e apresenta riscos biológicos. Assim, este estudo avaliou diferentes concentrações da lipoproteína de baixa densidade (LDL), em substituição à gema de ovo, para a confecção de diluentes para criopreservação espermática em ovinos. Foram utilizados um diluidor controle (CTR= 20% de gema de ovo) e cinco tratamentos, substituindo-se a gema pelas diferentes proporções de LDL (T1=6%; T2=8%; T3=12%; T4=16%; T5=20%), todos à base de TRIS-glicerol. Para o estudo, utilizaram-se dois ejaculados, de seis reprodutores da raça Santa Inês. Sessenta dias após a criopreservação, as amostras foram descongeladas e avaliadas subjetivamente quanto à motilidade total (MT, %) e progressiva (MP, %), ao vigor (1-5) e à integridade funcional (choque hisposmótico com água destilada, %) e estrutural (corante supravital eosina, %) das membranas espermáticas. As avaliações de vigor e funcionalidade de membrana não diferiram (P>0,05) entre os grupos. Entretanto, os grupos T4 (P<0,01) e T5 (P<0,05) foram superiores ao CTR para os parâmetros MT, MP e integridade estrutural de membrana, o que confirma que as LDLs podem ser alternativas eficientes para substituição da gema de ovo em diluidores para criopreservação de sêmen ovino.(AU)


The use of egg yolk makes it difficult to standardize extenders and presents biological hazards. Thus, this study evaluated different concentrations of low-density lipoprotein (LDL) to replace yolk extenders for production of sperm for cryopreservation in ovine. A control extender was used (CTR= 20% yolk) and five treatments, replacing the yolk by different ratios of LDL (T1= 6%; T2= 8%, T3= 12%; T4= 16%; T5= 20%) all based on TRIS-glycerol. For the study, two ejaculates from six Santa Ines breeding were used. Sixty days after cryopreservation, the samples were thawed and evaluated for total motility (MT, %) and progressive motility (MP, %), vigor (1-5) and the functional integrity (hyposmotic shock with distilled water, %) and structural (supravital dye eosin, %) of the sperm membranes. The evaluations of strength and membrane functionality didn't differ (P> 0.05) between groups. However, T4 (P< 0.01) and T5 (P< 0.05) groups were superior to the CTR for the MT, MP, and membrane structural integrity parameters, which confirms that LDLs can be efficient alternatives for yolk replacement in extenders for cryopreservation of ovine semen.(AU)


Assuntos
Animais , Masculino , Preservação do Sêmen/métodos , Ovinos , Criopreservação/veterinária , Lipoproteínas LDL/administração & dosagem
8.
Animal ; 13(11): 2679-2686, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31064578

RESUMO

Crossbreeding represents an important technique to improve growth, beef quality and adaptability in beef production systems in tropical countries. The aim of this study was to evaluate sire and dam breed effects on performance and carcass traits of crossbred cattle produced in a tropical environment. Heifers and steers were evaluated during the pre-weaning, the post-weaning (n = 173) and the finishing phase (n = 123). Animals were produced by mating Nellore (N_N), Angus × Nellore (A_N) and Caracu × Nellore (C_N) dams with Braford, Charbray and Caracu sires. After weaning, animals were raised grazing on Marandu grass for 12 months; thereafter they were housed in individual pens and finished in a feedlot, receiving a total mixed ration. Ultrasound carcass evaluations were performed to determine ribeye area (R_A), backfat thickness (B_T) and rump fat thickness (R_T). A_N progeny were heavier at birth than N_N (P < 0.05), and Braford progeny had greater birth BW than Caracu (P < 0.05). Greater weaning BW was observed in the A_N and C_N offspring compared to N_N (P < 0.01). Greater average daily gain during the post-weaning period was verified in the N_N progeny compared to C_N (P < 0.05). No dam or sire breed effects were observed for BW at the end of the post-weaning period (P > 0.05). Progeny of N_N cows had greater B_T (P < 0.05) and R_T (P < 0.01) at the end of the post-weaning period in relation to C_N. Greater R_A was observed in the Caracu progeny than in the Braford (P < 0.05), which showed greater R_T than the Charbray progeny at the end of the post-weaning period (P < 0.05). No dam or sire breed effects were verified for final BW at the feedlot or for feed efficiency traits (P > 0.05). A_N progeny were superior in final B_T compared to C_N (P < 0.01), and Braford progeny had greater R_T at the end of finishing than Charbray (P = 0.05). The use of crossbred dams allows an increase in productivity until weaning, but this is not maintained in the post-weaning and finishing periods. The use of Braford sires produces similar growth performance in the different stages of the production system to those seen with Charbray and Caracu sires but generates animals with higher fat thickness at the end of finishing, which may improve carcass quality and commercial value.


Assuntos
Bovinos/fisiologia , Hibridização Genética , Carne Vermelha/normas , Animais , Composição Corporal , Cruzamento , Bovinos/genética , Bovinos/crescimento & desenvolvimento , Feminino , Masculino , Parto , Fenótipo , Gravidez , Ultrassonografia/veterinária , Desmame
9.
Dev Psychopathol ; 30(3): 725-742, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30068420

RESUMO

This article extends the research focusing on the early origins of psychopathology into the prenatal period, by exploring the association between maternal prenatal depression and offspring (fetal and infant) neurobehavior. The sample is recruited from a rural population in South India where women in the third trimester of pregnancy were assessed for depression and the heart rate responses of their fetuses to extrinsically applied vibroacoustic stimuli were studied. At 2 months postbirth, infant temperament and cortisol responsivity to immunization were assessed. The association between maternal prenatal depression and fetal responsivity to vibroacoustic stimulation, and infant responsivity to immunization, was U shaped with higher levels of responsivity noted in the offspring of mothers with very high and very low depression scores, and lower levels noted in the offspring of mothers with moderate depression scores. Maternal prenatal depression was not associated with infant temperament. The findings highlight the importance of environmental influences in the developmental origins of neurobehavior, suggesting that such differences, not evident at baseline, may emerge upon exposure to stressors. The study also emphasizes the need for further investigation in low- and middle-income contexts by providing preliminary evidence of the differing patterns of association observed between high- and low-income populations.


Assuntos
Transtorno Depressivo/fisiopatologia , Transtornos do Neurodesenvolvimento/fisiopatologia , Complicações na Gravidez/fisiopatologia , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Temperamento/fisiologia , Populações Vulneráveis , Adulto , Estudos de Coortes , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/psicologia , Feminino , Humanos , Hidrocortisona/sangue , Índia , Lactente , Recém-Nascido , Transtornos do Neurodesenvolvimento/diagnóstico , Transtornos do Neurodesenvolvimento/psicologia , Pobreza/psicologia , Gravidez , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/psicologia , Efeitos Tardios da Exposição Pré-Natal/psicologia , População Rural , Populações Vulneráveis/psicologia
10.
Lett Appl Microbiol ; 67(3): 235-243, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29856469

RESUMO

Streptococcus agalactiae is among the most relevant aetiologic agent of bovine clinical and subclinical mastitis, a major problem for the dairy industry. In Brazil, clonal diversity, capsular typing and multidrug resistance profiles of S. agalactiae related to human and bovine infections need further investigation. Presently, S. agalactiae isolates of bovine subclinical mastitis, from Brazilian Northeastern region, were submitted to capsular and pulsed-field gel electrophoresis (PFGE)-typing, antimicrobial susceptibility and assays of biofilm formation at different time incubation and pH levels. Sixteen bovine isolates were characterized by polymerase chain reaction assay as S. agalactiae capsular type II (CTII) and classified by PFGE in A1/A2 (n = 06), B1/B2 (n = 06), C (n = 03) and D (n = 01) patterns. Bovine S. agalactiae CTII strains were classified as 25% multidrug-resistant (MDR) with susceptibility to penicillin, linezolid and vancomycin. Biofilm formation on abiotic surface was strain- and time-dependent with significantly higher rates at pH 6·5. In conclusion, S. agalactiae capsular type II isolates recovered from bovine subclinical mastitis produced different pH-dependent biofilm levels. Our findings suggest that biofilm production is modulated by environmental factors and provides S. agalactiae advantageous in colonizing mammary gland during mastitis development, including MDR strains. SIGNIFICANCE AND IMPACT OF THE STUDY: Streptococcus agalactiae is among the most relevant aetiologic agent of bovine clinical and subclinical mastitis, a major problem for the dairy industry. The disease may cause significant economic loss due to decreased production and milk quality and increased use of medicaments. Presently, data demonstrated that biofilm formation favours the establishment of infectious process in health mammary tissue by S. agalactiae and emphasizes that an acidic pH promotes adhesion by biofilm-forming bacterial strains. S. agalactiae strains (25%) showed resistance to tetracycline, azithromycin, erythromycin and clindamycin, and consequently were classified as multidrug-resistant strains.


Assuntos
Biofilmes , Mastite Bovina/microbiologia , Leite/microbiologia , Streptococcus agalactiae/fisiologia , Animais , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Brasil , Bovinos , Farmacorresistência Bacteriana Múltipla , Feminino , Leite/química , Streptococcus agalactiae/efeitos dos fármacos , Streptococcus agalactiae/genética , Streptococcus agalactiae/isolamento & purificação
11.
BMC Cancer ; 18(1): 262, 2018 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-29514651

RESUMO

BACKGROUND: The aim of this study was to estimate the total economic and health related burden of breast cancer in the Netherlands. METHODS: Data on incidence, prevalence, mortality and survival were extracted from the Dutch National Cancer Registry and were used to calculate the economic and health related burden of breast cancer for overall, DCIS (stage 0), early- (stage I), locally advanced- (stage II-III) and metastatic- (stage IV) breast cancer by age groups and by year (if applicable). RESULTS: The overall incidence of breast cancer increased from 103.4 up to 153.2 per 100,000 women between 1990 and 2014. The increase was driven by DCIS and early breast cancer as the incidence of locally advanced and metastatic breast cancer remained stable. Between 1990 and 2014, ten-year overall survival rates increased from 87% to 93% for early breast cancer, 41% to 62% for locally advanced- and from 6% to 9% for metastatic disease. Annually, breast cancer in the Netherlands is responsible for approximately 3100 deaths, 26,000 life years lost, 65,000 Disability Adjusted Life Years (DALYs) and an economic burden of €1.27 billion. CONCLUSIONS: This study provides a comprehensive assessment of the burden of breast cancer and subsequent trends over time in the Netherlands.


Assuntos
Neoplasias da Mama/epidemiologia , Carcinoma Ductal de Mama/epidemiologia , Carcinoma Intraductal não Infiltrante/epidemiologia , Anos de Vida Ajustados por Qualidade de Vida , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/economia , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/economia , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/economia , Carcinoma Intraductal não Infiltrante/patologia , Efeitos Psicossociais da Doença , Feminino , Seguimentos , Humanos , Incidência , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Prevalência , Prognóstico , Sistema de Registros , Taxa de Sobrevida , Carga Tumoral , Adulto Jovem
12.
Animal ; 12(9): 1807-1814, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29268814

RESUMO

Longer-lived cows tend to be more profitable and the stayability trait is a selection criterion correlated to longevity. An alternative to the traditional approach to evaluate stayability is its definition based on consecutive calvings, whose main advantage is the more accurate evaluation of young bulls. However, no study using this alternative approach has been conducted for Zebu breeds. Therefore, the objective of this study was to compare linear random regression models to fit stayability to consecutive calvings of Guzerá, Nelore and Tabapuã cows and to estimate genetic parameters for this trait in the respective breeds. Data up to the eighth calving were used. The models included the fixed effects of age at first calving and year-season of birth of the cow and the random effects of contemporary group, additive genetic, permanent environmental and residual. Random regressions were modeled by orthogonal Legendre polynomials of order 1 to 4 (2 to 5 coefficients) for contemporary group, additive genetic and permanent environmental effects. Using Deviance Information Criterion as the selection criterion, the model with 4 regression coefficients for each effect was the most adequate for the Nelore and Tabapuã breeds and the model with 5 coefficients is recommended for the Guzerá breed. For Guzerá, heritabilities ranged from 0.05 to 0.08, showing a quadratic trend with a peak between the fourth and sixth calving. For the Nelore and Tabapuã breeds, the estimates ranged from 0.03 to 0.07 and from 0.03 to 0.08, respectively, and increased with increasing calving number. The additive genetic correlations exhibited a similar trend among breeds and were higher for stayability between closer calvings. Even between more distant calvings (second v. eighth), stayability showed a moderate to high genetic correlation, which was 0.77, 0.57 and 0.79 for the Guzerá, Nelore and Tabapuã breeds, respectively. For Guzerá, when the models with 4 or 5 regression coefficients were compared, the rank correlations between predicted breeding values for the intercept were always higher than 0.99, indicating the possibility of practical application of the least parameterized model. In conclusion, the model with 4 random regression coefficients is recommended for the genetic evaluation of stayability to consecutive calvings in Zebu cattle.


Assuntos
Cruzamento , Bovinos , Animais , Bovinos/genética , Bovinos/fisiologia , Feminino , Modelos Lineares , Modelos Genéticos , Parto , Fenótipo , Gravidez
13.
Arq. bras. med. vet. zootec. (Online) ; 70(3): 722-730, maio-jun. 2018. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-911194

RESUMO

Objetivou-se, com este estudo, caracterizar o efeito do microclima proporcionado por dois ambientes distintos, sobre as respostas fisiológicas de vacas F1 HxZ em fase de lactação, durante o verão. Foram avaliadas 34 vacas oriundas de quatro diferentes grupos genéticos F1 HxZ. Durante o período experimental, foram feitas medições diárias das variáveis ambientais: temperatura do ar, umidade relativa do ar e temperatura de globo negro, para cálculo dos valores de ITGU. Os parâmetros fisiológicos frequência respiratória, batimento cardíaco, temperatura de superfície corporal, temperatura retal e taxa de sudação foram obtidos às 7h e às 14 horas. A pesagem do leite foi feita semanalmente. Os animais F1 avaliados não apresentaram alterações fisiológicas, e não houve redução na produção láctea em função dos ambientes de criação. O ITGU atingiu valores considerados estressantes (87,7), porém os ambientes de criação não proporcionaram estresse nem redução na produção dos animais.(AU)


The objective of this study was to characterize the effect of microclimate provided by two distinct environments on the physiological responses of F1 HxZ cows lactating during the summer, where 34 cows were evaluated originating from 4 different genetic groups F1 HxZ. During the trial period, daily measurements of environmental variables were determined: dry bulb temperature, relative humidity and black globe temperature, to calculate the BGT values. The physiological parameters respiratory rate, heart rate, body surface temperature, rectal temperature, and sweat rate were obtained at 07:00 and 14:00h. Weighing of milk was done weekly. The F1 animals evaluated did not present physiological changes, nor was there a reduction in milk production as a function of breeding environments. The BGT reached levels considered stressful (87.7), but the breeding environments provided no stress or reduced production of animals.(AU)


Assuntos
Animais , Feminino , Bovinos , Transtornos de Estresse por Calor/veterinária , Bem-Estar do Animal/tendências , Bovinos/fisiologia , Microclima
14.
J Fish Biol ; 91(4): 1109-1122, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28884814

RESUMO

A comparison of the genetic structure of Chimaera monstrosa populations from the Atlantic Ocean and the Mediterranean Sea was carried out using mitochondrial DNA analysis. Results indicate high and significant pairwise ΦST values with no shared haplotypes between the two areas. Furthermore, migration rate estimates suggested absence of gene flow between the two basins. These findings, coupled with the species vertical distribution, suggest that the shallow depth of the Strait of Gibraltar may act as a barrier limiting the dispersal capabilities of these populations, which likely became separated at the end of the middle Pleistocene.


Assuntos
DNA Mitocondrial/química , Peixes/genética , Fluxo Gênico , Variação Genética , Migração Animal , Animais , Oceano Atlântico , Peixes/fisiologia , Haplótipos , Mar Mediterrâneo , Filogenia , Isolamento Reprodutivo , Análise de Sequência de DNA
16.
Arq. bras. med. vet. zootec ; 68(6): 1563-1572, nov.-dez. 2016. tab
Artigo em Português | LILACS, VETINDEX | ID: biblio-827925

RESUMO

Com o objetivo de avaliar matrizes da raça Nelore (NE) e cruzadas 1/2 Angus + 1/2 Nelore (AN), 1/2 Caracu + 1/2 Nelore (CN) e 1/2 Senepol + 1/2 Caracu (SC) quanto à precocidade sexual em sistemas de recria a pasto, eficiência reprodutiva e desempenho produtivo das matrizes em cada grupo genético (GG), matrizes desses grupos foram produzidas por três safras. Foram avaliadas 40 matrizes AN, 37 CN, 51 NE e 43 SC. Para prenhez precoce, matrizes AN apresentaram taxa de prenhez de 92,2% contra 29,1% para CN, 22,6% para SC e 1,1% para NE. Na prenhez convencional, matrizes AN obtiveram 99,4%, 98,8% para CN, 84,4% para SC e 80,0% para NE. A reconcepção das matrizes AN foi 86,3%, 75,1% de CN, 49,6% de NE e 43,6% de SC. Matrizes AN tiveram menor média de idade ao primeiro parto em meses, 26,36±0,79, contra 31,33±0,86 para CN, 33,51±0,98 para SC e 38,08±0,74 para NE. Para peso ao desmame, crias three-cross das AN pesaram mais que as F1 das NE, por volta de 19%. Para relação de peso ao desmame, não houve diferenças estatísticas entre GG. Matrizes AN foram superiores às demais nos aspectos reprodutivos e produtivos, seguidas das matrizes CN.(AU)


With the aim of evaluating Nelore (NE), 1/2 Angus + 1/2 Nelore (AN), 1/2 Caracu + 1/2 Nelore (CN), and 1/2 Senepol + 1/2 Caracu (SC) females for sexual precocity on pasture backgrounding, reproductive efficiency and productive performance of cows and their calves of each genetic group (GG), animals of these groups were produced for three years. A total of 40 AN, 37 CN, 51 NE and 43 SC cows were evaluated. For early heifer pregnancy, AN cows had pregnancy rate of 92.2% compared to 29.1% for CN, 22.6% for SC and 1.1% for NE. For conventional heifer pregnancy AN obtained 99.4%, CN with 98.8%, SC with 84.4% and NE with 80.0%. The first reconception of AN cows were 86.3%, 75.1% for CN, 49.6% for NE and 43.6% for SC. AN cows also had lower age at first calving in months, 26.36±0.79, compared to 31.33±0.86 for CN, 33.51±0.98 for SC and 38.08±0.74 for NE. For weaning weigth the three-cross from AN were heavier than the F1s from NE, by a margin of 19%. For calf:cow weight ratio there was no statistical difference among GG. AN cows were superior to the others in both productive and reproductive aspects, followed by the CN cows.(AU)


Assuntos
Animais , Feminino , Bovinos , Coeficiente de Natalidade , Fertilidade , Reprodução , Maturidade Sexual , Desmame
17.
J Anim Breed Genet ; 133(6): 523-533, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27194586

RESUMO

The productivity of herds may be negatively affected by inbreeding depression, and it is important to know how intense is this effect on the livestock performance. We performed a comprehensive analysis involving five Zebu breeds reared in Brazil to estimate inbreeding depression in productive and reproductive traits. Inbreeding depression was estimated for 13 traits by including the individual inbreeding rate as a linear covariate in the standard genetic evaluation models. For all breeds and for almost all traits (no effect was observed on gestation length), the performance of the animals was compromised by an increase in inbreeding. The average inbreeding depression was -0.222% and -0.859% per 1% of inbreeding for linear regression coefficients scaled on the percentage of mean (ßm ) and standard deviation (ßσ ), respectively. The means for ßm (and ßσ ) were -0.269% (-1.202%) for weight/growth traits and -0.174% (-0.546%) for reproductive traits. Hence, inbreeding depression is more pronounced in weight/growth traits than in reproductive traits. These findings highlight the need for the management of inbreeding in the respective breeding programmes of the breeds studied here.


Assuntos
Bovinos/classificação , Bovinos/genética , Endogamia , Carne , Leite , Animais , Brasil , Bovinos/fisiologia
18.
Indian J Med Microbiol ; 34(2): 222-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27080779

RESUMO

Enteric fever is a public health problem with the upsurge in the occurrence of Salmonella isolates that are resistant to ciprofloxacin. In this study, a total of 284 blood culture isolates of S. Paratyphi A were investigated. Of these isolates, 281 (98.9%) were nalidixic acid resistant. A high rate (6.3%) of high-level resistance (≥ 4 µg/mL) was found to ciprofloxacin. The isolates with ciprofloxacin minimum inhibitory concentrations (MICs) of ≥ 12 µg/mL had 4 mutations, 2 mutations within the quinolone resistance-determining region of gyrA and 2 mutations also in parC. According to the Clinical Laboratory Standards Institute 2012 MIC breakpoints, 75.0% of isolates were resistant to ciprofloxacin. Finally, 3 major pulsed-field gel electrophoresis patterns were observed among the S. Paratyphi A isolates. The spread of fluoroquinolone resistant S. Paratyphi A necessitates a change toward 'evidence-based' treatment for enteric fever. The research provides a perspective on the increasing prevalence of antimicrobial resistant S. Paratyphi A isolates in this region of India.


Assuntos
Antibacterianos/farmacologia , Sangue/microbiologia , Farmacorresistência Bacteriana , Febre Paratifoide/microbiologia , Salmonella paratyphi A/efeitos dos fármacos , Salmonella paratyphi A/isolamento & purificação , Adolescente , Adulto , Idoso , Hemocultura , Criança , Pré-Escolar , Ciprofloxacina/farmacologia , DNA Girase/genética , DNA Topoisomerase IV/genética , Feminino , Fluoroquinolonas/farmacologia , Humanos , Índia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mutação , Ácido Nalidíxico/farmacologia , Prevalência , Adulto Jovem
19.
Br J Surg ; 103(6): 644-655, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26990850

RESUMO

BACKGROUND: With the increasing use of neoadjuvant chemotherapy and minimally invasive ablative therapy in breast cancer, pretreatment assessment of tumour grade on core needle biopsy (CNB) is increasingly needed. However, grading on CNB is possibly less accurate than grading based on the surgical excision specimen. A systematic review and meta-analysis of the literature was conducted to derive a reliable estimate of the agreement in tumour grading between CNB and subsequent surgical excision. METHODS: Following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) criteria, Embase, PubMed and the Cochrane Library were searched. Pooled proportions of agreement in grading between CNB and the excision specimen, Cohen's κ and percentages of overestimation and underestimation were calculated. Random-effects models were applied because of substantial heterogeneity, assessed by I2 test. Determinants of the level of agreement in grading were explored with meta-regression. RESULTS: Thirty-four articles were included in the systematic review (6029 patients) and 33 in the meta-analysis (4980 patients). Pooled agreement and κ were 71·1 (95 per cent c.i. 68·8 to 73·3) per cent and 0·54 (0·50 to 0·58) respectively. Underestimation and overestimation occurred in 19·1 (17·1 to 21·3) and 9·3 (7·7 to 11·4) per cent respectively. Meta-regression showed associations between agreement of histological type (positive association) and proportion of patients with oestrogen receptor-positive disease (negative association) and grade agreement. CONCLUSION: Grading on CNB corresponds moderately with grading based on excision specimens, with underestimation in about one in five patients. Incorrect CNB tumour grading has limited clinical implications, as multiple factors influence decision-making for adjuvant systemic therapy.


Assuntos
Biópsia com Agulha de Grande Calibre/métodos , Neoplasias da Mama/patologia , Mama/patologia , Feminino , Humanos , Mastectomia/métodos , Gradação de Tumores
20.
Cell Death Dis ; 6: e1632, 2015 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-25675292

RESUMO

Eosinophils are effector cells that have an important role in the pathogenesis of allergic disease. Defective removal of these cells likely leads to chronic inflammatory diseases such as asthma. Thus, there is great interest in understanding the mechanisms responsible for the elimination of eosinophils from inflammatory sites. Previous studies have demonstrated a role for certain mediators and molecular pathways responsible for the survival and death of leukocytes at sites of inflammation. Reactive oxygen species have been described as proinflammatory mediators but their role in the resolution phase of inflammation is poorly understood. The aim of this study was to investigate the effect of reactive oxygen species in the resolution of allergic inflammatory responses. An eosinophilic cell line (Eol-1) was treated with hydrogen peroxide and apoptosis was measured. Allergic inflammation was induced in ovalbumin sensitized and challenged mouse models and reactive oxygen species were administered at the peak of inflammatory cell infiltrate. Inflammatory cell numbers, cytokine and chemokine levels, mucus production, inflammatory cell apoptosis and peribronchiolar matrix deposition was quantified in the lungs. Resistance and elastance were measured at baseline and after aerosolized methacholine. Hydrogen peroxide accelerates resolution of airway inflammation by induction of caspase-dependent apoptosis of eosinophils and decrease remodeling, mucus deposition, inflammatory cytokine production and airway hyperreactivity. Moreover, the inhibition of reactive oxygen species production by apocynin or in gp91(phox-/-) mice prolonged the inflammatory response. Hydrogen peroxide induces Eol-1 apoptosis in vitro and enhances the resolution of inflammation and improves lung function in vivo by inducing caspase-dependent apoptosis of eosinophils.


Assuntos
Eosinófilos/citologia , Eosinófilos/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Peróxido de Hidrogênio/uso terapêutico , Inflamação/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Asma , Western Blotting , Linhagem Celular , Eosinófilos/metabolismo , Humanos , Inflamação/induzido quimicamente , Inflamação/metabolismo , Leucócitos , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pleurisia , Espécies Reativas de Oxigênio/metabolismo
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