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1.
Animals (Basel) ; 11(6)2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34203615

RESUMO

Two of the most important problems in high-yielding dairy goat farms are early and accurate pregnancy diagnosis and the appropriate dry off of lactating does before the next kidding. The hypothesis posits that it could be possible to identify pregnant does through maximum progesterone milk levels at any time during the pregnancy, and that there is an optimal time to apply a lactation inhibitor to help dry off lactating does. Therefore, 114 Murciano-Granadina breed goats were used, from which 74 goats were inseminated at week 20 of lactation and samples of milk from pregnant and non-pregnant goats were taken at two-week intervals. The average maximum progesterone milk levels were higher outside the natural breeding season (40° latitude) than in the breeding season (11.6 ± 1.13 vs. 8.6 ± 1.02 ng/mL), although the levels from pregnant and non-pregnant goats were similar (10.85 ± 1.3 vs. 9.74 ± 1.6 ng/mL), except in the case of pregnancy with four foetuses (12.5 ± 1.3 ng/mL). Milk yield at mating does not affect fertility until a value of at least 3250 mL/day. Pregnancy started to affect milk yield up to the +7th week and was 59.9% lower in the +10th week after mating, so the use of lactation inhibitors could be more effective from this latter week. In conclusion, the results show that it is not possible to detect gestation in goats reliably through the maximum concentration of progesterone in milk at any time during lactation, except in the case of goats gestating four foetuses, that the milk yield of goats at mating does not affect fertility until a value of at least 3250 mL/day, and that from the 10th week post-mating, the application of lactation inhibitors would be optimal.

2.
Reprod Biol Endocrinol ; 14(1): 27, 2016 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-27170005

RESUMO

BACKGROUND: During cytoplasmic oocyte maturation, Ca(2+) currents are vital for regulating a broad range of physiological processes. Recent studies have demonstrated that DMSO and EG cause large transient increases in intracellular Ca(2+) in mouse oocytes. The CP used in vitrifying protocols also increases the intracellular calcium transient. The aim of this study is to evaluate the effects of vitrifying time (before and after IVM) and exposure to the vitrification solutions and ionomycin on oocyte quality and embryonic development. METHODS: 221 GV-oocytes unsuitable for IVF-ICSI cycles were randomly distributed into one of the following three groups. G1 (control group): 41 GV-oocytes IVM until MII; G2: 43 oocytes vitrified at GV stage and IVM until MII stage; and G3: 53 GV-oocytes IVM until MII and then vitrified. In order to clarify the effect of vitrification solutions (VS) on human oocyte IVM through the intracellular Ca(2+) oscillation, the following two groups were also included. G4: 43 GV-oocytes exposed to VS and IVM until MII; and G5: 41 GV-oocytes exposed to ionomycin and IVM until MII. All GV-oocytes that reached MII-stage were parthenogenetically activated to assess oocyte viability. IVM was performed in IVF-medium (24-48 h). Chemical treatment (ionomycin) and osmotic treatment (vitrification solutions) were performed without liquid-N2 immersion. The following rates were evaluated: survival (SR), in-vitro maturation (IVMR), activation (AR), development to 2-cell (DRC), development to morula (DRCM) and development to blastocyst (DRB). Ratios between the different treatment groups were compared using contingency tables analysis (chi-square test). RESULTS: A high survival rate was obtained in G2 (95.5 %) and G4 (96.6 %). In-vitro maturation rate was significantly higher for G4 (86 %) and G2 (83.7 %) compared to G1 (63.4 %), G3 (56.6 %) and G5 (48.8 %). DRCM was significantly higher for G1 and G2 compared to G3 (G1: 15.8 %, G2: 20.7 % and G3: 0 %). DRB was only obtained for the oocytes vitrified before IVM (G2: 3.4 %). AR was also significantly higher for G2 and G4 compared to G5 (G2: 80.5 %, G4: 86.5 % and G5: 55 %). DRCM and DRB were only obtained in G2 and G4. DRCM was significantly higher for oocytes vitrified at GV stage (G2) and for oocytes exposed to the VS in G4 compared to the oocytes exposed to the ionomycin in G5 (G2: 20.7 %; G4: 37.5 % and G5: 0 %). CONCLUSIONS: Vitrifying GV-oocytes improves their IVM. Further investigation could look to increase the oocyte pool and improve fertility preservation options.


Assuntos
Técnicas de Maturação in Vitro de Oócitos/métodos , Oócitos/crescimento & desenvolvimento , Pressão Osmótica , Vitrificação , Adulto , Cálcio/metabolismo , Sobrevivência Celular , Meios de Cultura , Desenvolvimento Embrionário , Feminino , Preservação da Fertilidade , Humanos
3.
Fertil Steril ; 102(4): 1022-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25064404

RESUMO

OBJECTIVE: To demonstrate the usefulness of image analysis in designing objective embryonic morphometric variables. DESIGN: Retrospective study of 214 top-quality day-2 embryo photographs from 50 double-embryo transfers resulting in no pregnancy (group 0) and 57 resulting in twin pregnancy (group 1). SETTING: Human reproduction unit. PATIENT(S): Study of 107 in vitro fertilization-intracytoplasmic sperm injection (IVF-ICSI) cycles in women age <36 years with double-embryo transfer of top-quality embryos. Only the first cycle of IVF-ICSI was included. INTERVENTION(S): Standard IVF-ICSI protocols. MAIN OUTCOME MEASURE(S): The embryo photographs were analyzed using the ImageJ program. The effects of the embryo variables and the clinical variables on embryo implantation were evaluated using a stepwise dichotomous logistic regression. RESULT(S): Significant differences were observed, owing to the women's ages, internal perimeter, roundness factor, and zona pellucida thickness. Embryos with smaller internal perimeter, circular shape, and thinner zona pellucida were more likely to implant. CONCLUSION(S): Morphometric variables lower the subjectivity of the current embryo grading systems. These variables are nonsubjective factors to consider when predicting implantation. Embryo image analysis is an accurate tool that can improve IVF-ICSI outcomes and reduce the number of twin pregnancies.


Assuntos
Implantação do Embrião , Transferência Embrionária , Embrião de Mamíferos/citologia , Fertilização in vitro , Adulto , Fatores Etários , Feminino , Humanos , Modelos Logísticos , Razão de Chances , Valor Preditivo dos Testes , Gravidez , Gravidez de Gêmeos , Estudos Retrospectivos , Injeções de Esperma Intracitoplásmicas , Fatores de Tempo
4.
Sensors (Basel) ; 12(5): 5752-74, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22778611

RESUMO

The rearing of poultry for meat production (broilers) is an agricultural food industry with high relevance to the economy and development of some countries. Periodic episodes of extreme climatic conditions during the summer season can cause high mortality among birds, resulting in economic losses. In this context, ventilation systems within poultry houses play a critical role to ensure appropriate indoor climatic conditions. The objective of this study was to develop a multisensor system to evaluate the design of the ventilation system in broiler houses. A measurement system equipped with three types of sensors: air velocity, temperature and differential pressure was designed and built. The system consisted in a laptop, a data acquisition card, a multiplexor module and a set of 24 air temperature, 24 air velocity and two differential pressure sensors. The system was able to acquire up to a maximum of 128 signals simultaneously at 5 second intervals. The multisensor system was calibrated under laboratory conditions and it was then tested in field tests. Field tests were conducted in a commercial broiler farm under four different pressure and ventilation scenarios in two sections within the building. The calibration curves obtained under laboratory conditions showed similar regression coefficients among temperature, air velocity and pressure sensors and a high goodness fit (R(2) = 0.99) with the reference. Under field test conditions, the multisensor system showed a high number of input signals from different locations with minimum internal delay in acquiring signals. The variation among air velocity sensors was not significant. The developed multisensor system was able to integrate calibrated sensors of temperature, air velocity and differential pressure and operated successfully under different conditions in a mechanically-ventilated broiler farm. This system can be used to obtain quasi-instantaneous fields of the air velocity and temperature, as well as differential pressure maps to assess the design and functioning of ventilation system and as a verification and validation (V&V) system of Computational Fluid Dynamics (CFD) simulations in poultry farms.


Assuntos
Criação de Animais Domésticos , Clima , Aves Domésticas , Animais , Calibragem , Temperatura
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