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1.
Int J Mol Sci ; 21(5)2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32111034

RESUMO

Fibroblast growth factors (FGF) play an important role during embryo development. To date, the role of FGF and the respective receptors (FGFR) during the preimplantation phase in cattle are not fully characterized. We examined FGF1, FGF2, FGFR1, FGFR2, and FGFR3 in cyclic and early pregnant heifers at Days 12, 15, and 18 after insemination (Day 0). Endometrial FGF1 mRNA transcript abundance in heifers varied significantly with respect to the day after insemination, the pregnancy status, and their interaction. The expression was higher in nonpregnant than in pregnant heifers at Day 18. The conceptus transcripts abundance of FGFR2 and FGFR3 were significantly lower at Day 15 than 18. In the endometrium, FGF1 protein abundance significantly decreased from Day 12 onwards and FGF2 protein abundance showed a minor, but a significant increase at Day 15 in comparison to Days 12 and 18. We concluded that the decrease in FGF1 mRNA expression in pregnant heifers at Day 18 points towards a potential contribution of FGF1 in the preimplantation process. Additionally, successful embryo elongation might require a spatiotemporal FGF2 protein increase in the endometrium.


Assuntos
Embrião de Mamíferos/metabolismo , Endométrio/metabolismo , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/metabolismo , Animais , Bovinos , Desenvolvimento Embrionário/genética , Desenvolvimento Embrionário/fisiologia , Endométrio/citologia , Epitélio/metabolismo , Epitélio/patologia , Feminino , Fator 1 de Crescimento de Fibroblastos/genética , Fator 1 de Crescimento de Fibroblastos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/genética , Receptor Tipo 3 de Fator de Crescimento de Fibroblastos/metabolismo
2.
Int J Mol Sci ; 21(2)2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31952188

RESUMO

Vascular endothelial growth factor A (VEGFA) plays a critical angiogenic role in the endometrium of placentalia during preimplantation. The role of VEGFA and its receptors is not fully characterised in bovine reproduction. We analysed the mRNA expression of VEGFA isoforms 121, 165 and 189, and VEGF receptors 1 and 2 in three experimental settings (A, B and C). We compared intercaruncular endometrium of cyclic to pregnant heifers at Days 12, 15 and 18 post insemination (Day 0), and between Day 15 and Day 18 conceptuses (A). We further compared caruncular versus intercaruncular endometrium at Day 15 (B), and endometrium of heifers carrying embryos originating from somatic cell nuclear transfer (SCNT) versus in vitro fertilisation (IVF) at Day 18 (C). Endometrial VEGFA protein was localised and quantified. Pregnant heifers displayed lower intercaruncular endometrial mRNA expression of VEGFA-121 (p = 0.045) and VEGFA-189 (p = 0.009) as well as lower VEGFA protein abundance (p < 0.001) at Day 15. The VEGFA protein was localised in intercaruncular luminal, glandular epithelium and in tunica muscularis of blood vessels. At Day 15, caruncular endometrium displayed higher VEGFA mRNA expression than intercaruncular endometrium (p < 0.05). Intercaruncular endometrial VEGFA protein at Day 18 was higher in abundance in SCNT than in IVF (p = 0.038). Therefore, during preimplantation in cattle, there may be a need for timely physiological reduction in intercaruncular endometrial VEGFA expression in favour of the caruncular area to facilitate a gradient towards the implantation sites. A higher expression of VEGFA in SCNT may predispose for later placentation abnormalities frequently observed following SCNT.


Assuntos
Blastocisto/metabolismo , Endométrio/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Animais , Bovinos , Desenvolvimento Embrionário/genética , Endométrio/embriologia , Estradiol/sangue , Feminino , Fertilização in vitro/métodos , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Transferência Nuclear , Gravidez , Progesterona/sangue , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo
3.
Trop Anim Health Prod ; 49(2): 251-258, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27826688

RESUMO

Milk production in Malawi is stagnating while steadily increasing in neighboring countries. We performed a literature review to identify factors negatively affecting milk production in Malawi and propose potential solutions to overcome the particular constraints. We structured the analysis along the value chain with three major components: upstream providers, on-farm production, and downstream providers. It is shown that the literature strongly focuses on on-farm constraints and most prominently on animal health, breed choice, and milk yield. The literature research did not reveal any reasons specific to Malawi that would hinder an increase in milk production as experienced in neighboring countries. We suggest a focus on crossbreeds accompanied by local breeding programs, which would reduce dependence on imported semen and strengthen the currently unreliable artificial insemination services. In addition, crossbreeds may be better suited than pure breeds for current feeding practices and climate conditions and thus come close to reaching their genetic potential. We conclude that cost advantages of crossbreeds clearly compensate for the lower revenues compared with exotic breeds such as Holstein-Friesian or Jersey.


Assuntos
Bovinos/fisiologia , Indústria de Laticínios/métodos , Leite/economia , Animais , Indústria de Laticínios/economia , Malaui
4.
J Dairy Res ; 80(1): 45-50, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23164053

RESUMO

The objective was to identify predisposing factors for increased risk of involuntary culling in adult Holstein-Friesian dairy cows. Data were sourced from Scotland's Rural College (SRUC) Dairy Research Centre. Between September 2003 and August 2010 175 cows were culled, a herd culling rate of 33.7%. The major reasons for involuntary culling were fertility (27.4%) and udder problems (26.9%). In the analysis, the culled cows were matched with their cohorts that survived to a later lactation. To identify predisposing factors, a binary logistic model was applied. Cows with higher than average body condition score (BCS) at last service were five times [Odds Ratio (OR) = 4.8] more likely to be culled due to infertility. Cows with low protein yield on day 60 ± 5 in lactation were ten times less likely (OR = 0.1) to be culled. In first lactation heifers, only BCS at last service increased the risk of involuntary culling due to infertility (OR = 13.0). A high milk yield acceleration was a significant (P = 0.04) factor in increasing the risk, five times (OR = 5.2) more, of culling cows due to udder problems. In conclusion, a high BCS at last service, high milk protein yield at around day 60 in lactation and acceleration of milk yield after calving exposed cows to a risk of being culled involuntarily. In practice, monitoring of traits that indicate metabolic imbalance could assist identifying cows at high risk of being culled and contribute to reducing the associated risk through a more effective timely decision.


Assuntos
Doenças dos Bovinos , Indústria de Laticínios/métodos , Lactação , Animais , Composição Corporal , Bovinos , Doenças dos Bovinos/metabolismo , Feminino , Infertilidade Feminina/veterinária , Mastite Bovina , Leite/química , Proteínas do Leite/análise , Escócia
5.
Sci Afr ; 20: e01686, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37192885

RESUMO

Coronavirus disease 2019 (COVID-19) was a global health crisis. Its effects did not spare the smallholder farmers. This study aimed at assessing smallholder farmers' perceived potential impact of COVID-19 on their livelihood in Malawi. During the first wave of the COVID-19, 606 smallholder farmers residing in 12 districts in Malawi were interviewed through an online survey. Farmers' knowledge, attitudes, and practices on COVID-19 were evaluated. Results showed that 81% of the farmers had knowledge on transmission, prevention, signs and symptoms, groups which were at high risk, and that there was no availability of COVID-19 treatment. The majority of the farmers (96%) reported that the measures which the Government of Malawi instituted to contain the spread of the disease were effective. All the farmers interviewed reported practicing at-least one of the preventive measures as advised by the Government through the Ministry of Health. Ninety nine percent of the farmers reported that they would report using the channels designated by the Government through the Ministry of Health if they suspected that one has symptoms of COVID-19. The critical sources of COVID-19 information for the farmers were radio and television stations (80%), and digital platforms (73%). Based on the farmers' views, the first wave of the disease negatively impacted their income (85%) and food (63%) sources. These results pinpoint the need for COVID-19 inclusive programming in existing and new developmental initiatives targeting smallholder farmers.

6.
Theriogenology ; 144: 174-184, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31972461

RESUMO

Evaluation of dietary interventions with regard to fertility problems often observed in ruminant livestock is of global interest. Though the effects of polyphenol supplementation in ruminants on digestion and food quality are well described, the impact on reproductive tissues and fluids remains scarcely investigated. These compounds protect dietary unsaturated fatty acids (FA) from oxidation and biohydrogenation and thus saturation. In addition, modification of the expression of genes associated with FA metabolism may occur. Therefore, we characterized for the first time the FA profiles of reproductive tissues and fluids and investigated their potential modification by dietary polyphenols in 22 cyclic ewes. The animals were randomly divided into four groups and fed a basal diet of meadow hay and one of four concentrate types either non-supplemented (control) or supplemented with grape seed extract, Acacia mearnsii bark extract (13 g/kg dry matter (DM) each) or a combination of both (26 g/kg DM). After 10 weeks of feeding, the animals were slaughtered. Samples of reproductive (oviduct, uterus) and metabolically differently active tissues (liver, muscle, adipose) as well as of plasma and fluids from oviduct and uterus were analysed for their FA composition. In addition, the expression of lipid metabolic and antioxidant genes was analysed in all tissues except the adipose tissue. Fatty acid profiles in tissues and fluids as well as gene expression in tissues significantly differed between the different fluids and tissues. In contrast, only a few diet and matrix (fluid or tissue) × diet interactions were observed. Still, the FA profile of the uterus was the only one not at all affected by the diet. The mRNA expression was not affected by the diet for most of the genes investigated, which might in part be explained by the similar plasma polyphenol concentrations found at slaughter. Overall, our findings contribute to an improved understanding of the characteristic FA composition of reproductive tissues and fluids in sheep. In addition, the effect of polyphenols on different tissues, fluids and tissue gene expression has been confirmed as described in other animal species.


Assuntos
Dieta/veterinária , Ácidos Graxos/metabolismo , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Ovinos/fisiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Feminino , Extratos Vegetais/química , Polifenóis/administração & dosagem , Polifenóis/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Distribuição Tecidual
7.
Anim Reprod Sci ; 213: 106268, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31987321

RESUMO

An alpine environment is unique due to pasture biodiversity, with an abundant content of natural antioxidant polyphenols. The present study investigated the effects of lowland and alpine grazing on the oviduct and uterine tissue redox status and amino acid concentrations in plasma and reproductive fluids. In the first experiment, heifers grazed on lowland (H-LOW: n = 13) and on alpine (H-ALP: n = 15) pastures. In the second experiment, heifers grazed on the same lowland (HS-LOW: n = 6) and on a different alpine (HS-ALP: n = 6) pasture. The abundance of mRNA transcripts for antioxidant enzymes in the oviduct (glutathione S-transferase alpha 2, glutathione synthetase (GSS)) and the endometrium (catalase, glutathione-disulfide reductase, GSS) was less (P <  0.05), and for glutathione peroxidase 4 in the endometrium greater (P =  0.006) in the H-LOW than in the H-ALP group. The abundance of mRNA transcript for catalase was less in the endometrium in the H-LOW than in the H-ALP (P =  0.001) group. Catalase and NAD(P)H quinone dehydrogenase 1 concentrations in the oviduct were greater in the HS-LOW than in the HS-ALP group (P <  0.05). Of 32 amino acids analysed, there were differences in concentrations in the H-LOW and H-ALP group of 13, seven and 15 in plasma, oviduct and uterine fluids, respectively (P <  0.05). Comparing the HS-LOW to the HS-ALP groups, there were 13, one and three amino acids in the plasma, oviduct and uterine fluids, respectively, that were differentially abundant (P <  0.05). The grazing systems had some effect on the redox status and amino acid patterns in reproductive tissues.


Assuntos
Aminoácidos/metabolismo , Criação de Animais Domésticos , Bovinos/fisiologia , Genitália Feminina/metabolismo , Altitude , Aminoácidos/química , Animais , Feminino , Genitália Feminina/química , Oxirredução
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