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1.
Reprod Domest Anim ; 59(8): e14701, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39109447

RESUMO

This study aimed to evaluate the effect of chemical gasification and HEPES as alternative systems to pH control during in vitro maturation on bovine oocytes competence. Groups of 20 bovine cumulus oocytes complexes (COCs) were randomly distributed and cultured for 24 h in one of the following experimental groups: (i) chemical reaction (ChRG) system: CO2 generated from sodium bicarbonate and citric acid reaction (ii) culture media TCM-HEPES (HEPES-G); and (iii) control group (CNTG) in conventional incubator. After in vitro maturation (IVM), the COCs were in vitro fertilized (IVF), and in vitro cultivated (IVC) in a conventional incubator. We evaluated oocyte nuclear maturation, cleavage and blastocyst rates, in addition to the relative mRNA expression of BAX, BMP-15, AREG and EREG genes in oocytes and cumulus cells. The proportion of oocytes in metaphase II was higher in CNTG and ChRG (77.57% and 77.06%) than in the HEPES-G (65.32%; p = .0408 and .0492, respectively). The blastocyst production was similar between CNTG and ChRG (26.20% and 28.47%; p = .4232) and lower (p = .001) in the HEPES-G (18.71%). The relative mRNA expression of BAX gene in cumulus cells was significantly higher (p = .0190) in the HEPES-G compared to the CNTG. Additionally, the relative mRNA expression of BMP-15 gene was lower (p = .03) in oocytes from HEPES-G compared to the CNTG. In conclusion, inadequate atmosphere control has a detrimental effect on oocyte maturation. Yet, the use of chemical gasification can be an efficient alternative to bovine COCs cultivation.


Assuntos
Fertilização in vitro , Técnicas de Maturação in Vitro de Oócitos , Oócitos , Animais , Bovinos , Técnicas de Maturação in Vitro de Oócitos/veterinária , Técnicas de Maturação in Vitro de Oócitos/métodos , Oócitos/efeitos dos fármacos , Fertilização in vitro/veterinária , Feminino , Meios de Cultura , Blastocisto/efeitos dos fármacos , Células do Cúmulo/efeitos dos fármacos , Dióxido de Carbono/farmacologia , Bicarbonato de Sódio/farmacologia , Ácido Cítrico/farmacologia , Técnicas de Cultura Embrionária/veterinária
2.
PeerJ ; 7: e8129, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31844569

RESUMO

BACKGROUND: Drones are reliable tools for estimating colonial seabird numbers. Although most research has focused on methods of improving the accuracy of bird counts, few studies have evaluated the impacts of these methods on bird behavior. In this study, we examined the effects of the DJI Phantom 3 drone approach (altitude, horizontal and vertical descent speeds) on changes in the intensity of behavioral response of guano birds: guanay cormorants (Phalacrocorax bougainvilli), Peruvian boobies (Sula variegata) and Peruvian pelicans (Pelecanus thagus). The breeding and non-breeding condition was also evaluated. METHODS: Eleven locations along the Peruvian coast were visited in 2016-2017. Drone flight tests considered an altitude range from 5 to 80 m from the colony level, a horizontal speed range from 0.5 to 15 m/s, and a vertical descent speed range from 0.5 to 3 m/s. The intensity of the behavioral response of birds was scored and categorized as: 0-no reacting, 1-head pointing to the drone (HP), 2-wing flapping (WF), 3-walking/running (WR) and 4-taking-off/flying (TK). Drone noise at specific altitudes was recorded with a sound meter close to the colony to discriminate visual from auditory effects of the drone. RESULTS: In 74% of all test flights (N = 507), guano birds did not react to the presence of the drone, whereas in the remaining flights, birds showed a sign of discomfort: HP (47.7%, N = 130), WF (18.5%), WR (16.9%) and TK (16.9%). For the drone approach tests, only flight altitude had a significant effect in the intensity of the behavioral response of guano birds (intensity behavioral response <2). No birds reacted at drone altitudes above 50 m from the colony. Birds, for all species either in breeding or non-breeding condition, reacted more often at altitudes of 5 and 10 m. Chick-rearing cormorants and pelicans were less sensitive than their non-breeding counterparts in the range of 5-30 m of drone altitude, but boobies reacted similarly irrespective of their condition. At 5 m above the colony, cormorants were more sensitive to the drone presence than the other two species. Horizontal and vertical flights at different speeds had negligible effects (intensity behavioral response <1). At 2 m above the ground, the noise of the cormorant colony was in average 71.34 ± 4.05 dB (N = 420). No significant differences were observed in the drone noise at different flight altitudes because the background noise of the colony was as loud as the drone. CONCLUSIONS: It is feasible to use the drone DJI Phantom 3 for surveys on the guano islands of Peru. We recommend performing drone flights at altitudes greater than 50 m from guano bird colonies and to select take-off spots far from gulls. Likewise, this study provides a first step to develop guidelines and protocols of drone use for other potential activities on the Peruvian guano islands and headlands such as surveys of other seabirds and pinnipeds, filming and surveillance.

3.
Environ Pollut ; 252(Pt B): 1709-1718, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31284213

RESUMO

A Fenton like advanced oxidation process (AOP) employing scrap zerovalent iron (SZVI) and hydrogen peroxide (H2O2) was studied for industrial textile wastewater treatment from a textile manufacturing plant located at Medellín, Colombia (South America). The wastewater effluent studied contains a mixture of organic compounds resistant to conventional treatments. The effect of initial pH and SZVI concentration and H2O2 concentration were studied by a response surface methodology (RSM) Box-Behnken design of experiment (BBD). The combined SZVI/H2O2 process led to reductions of 95% color, 76% of chemical oxygen demand (COD) and 71% of total organic carbon (TOC) at optimal operating conditions of pH = 3, SZVI = 2000 mg/L and [H2O2] = 24.5 mM. Molecular weight distribution measurement (MWD), ultraviolet-visible (UV-Vis) spectroscopy, HPLC, biodegradability and toxicity were used to characterize the pollutants after the treatment process finding that the resulting effluent was polluted mostly by low molecular weight carboxylic acids. A remarkable biodegradability enhancement of the effluent was evidenced by a BOD5/COD ratio increase from 0.22 to 0.4; also, the SZVI/H2O2 process successfully reduced the toxicity from 60% to 20% of dead A. Salina crustaceans.


Assuntos
Ácidos Carboxílicos/análise , Peróxido de Hidrogênio/química , Ferro/química , Indústria Têxtil , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Biodegradação Ambiental , Análise da Demanda Biológica de Oxigênio , Ácidos Carboxílicos/toxicidade , Colômbia , Concentração de Íons de Hidrogênio , Modelos Teóricos , Oxirredução , Poluentes Químicos da Água/toxicidade
4.
Vet J ; 205(1): 101-3, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26021888

RESUMO

The aim of the present study was to characterize single nucleotide polymorphisms (SNPs) in the promoter region of the bovine paraoxonase 1 (PON1) gene and determine their relationship with PON1 serum activity. Blood samples were collected from 47 Holstein cows during the periparturient period. Serum PON1 was measured and DNA extracted for PCR and sequencing of the promoter region of the PON1 gene. Seven novel SNPs were identified and of these, five SNPs, at positions -105, -221, -392, -611 and -674, upstream of the start of the published mRNA sequence (NM_001046269.2), were found to be associated with variability in serum PON1 activity (P < 0.05). The SNPs at positions -221 and -611 were located in regions predicted to bind to transcription factors linked to the acute phase response.


Assuntos
Arildialquilfosfatase/genética , Bovinos/metabolismo , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Animais , Arildialquilfosfatase/sangue , Indústria de Laticínios , Feminino , Período Pós-Parto
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