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Archives Animal Breeding | 2013

Seasonal changes in scrotal circumference, the quantity and quality of ram semen in hungary

János Oláh; Szilvia Kusza; Sándor Harangi; János Posta; András Kovács; Anna Pécsi; Csilla Budai; András Jávor

Abstract. In this study, the quantitative and qualitative traits of semen were studied in seven rams of different breeds (Prolific Merino, Cokanski Tsigai, Barbados Blackbelly, Babolna Tetra, Awassi, Ile de France and Suffolk), bred in Hungary. The semen parameters (density, volume, pH, mass motility, % motility, thawing and heat resistance), freezability of semen and the factors influencing these parameters were evaluated with respect to breed and season. The fresh and post-thawing quality of semen varied greatly with the breed and the season. The postthawing motility of semen cells was outstandingly high for Awassi rams in three seasons. During the test period, the smallest scrotal circumference was measured for Barbados Blackbelly, except for the summer when it increased by 12.5 cm. The reintroduction of artificial insemination could lead to a significant advancement of the sheep sector in Hungary. To promote this, we have provided useful and new information for breeders and organisations.


Acta Biologica Hungarica | 2017

Changes in expression of neuropeptides and their receptors in the hypothalamus and gastrointestinal tract of calorie restricted hens

Ádám Simon; János Oláh; István Komlósi; András Jávor; József Németh; Zoltán Szilvássy; Dóra Reglődi; Andrea Tamas; Levente Czeglédi

The list of orexigenic and anorexigenic peptides, those are known to alter feed intake, is continuously growing. However, most of them are studied in mammalian species. We aimed to investigate plasma level and mRNA expression of the pituitary adenylate cyclase-activating polypeptide (PACAP), gene expression of its receptor (PAC1), furthermore the gene expression of galanin (GAL), neuromedin U (NMU), and its two receptors (NMUR1 and NMUR2) in the hypothalamus, proventriculus, and jejunum of hens exposed to 40% calorie restriction. Feed restriction resulted in a 88% increase in mRNA and a 27% increase in peptide level of PACAP in proventriculus measured with qPCR and RIA, respectively. Increases were found in the gene expression of PAC1 (49%) and NMUR1 (63%) in the hypothalamus. Higher expressions of peptide encoding genes (76% for PACAP, 41% for NMU, 301% for NMUR1 and 308% for GAL, P < 0.05) were recorded in the jejunum of hens exposed to restricted nutrition. The results indicate that PACAP level responds to calorie restriction in the proventriculus and jejunum, but not in the hypothalamus and plasma.


Acta Biochimica Polonica | 2018

Feeding state and age dependent changes in melanin-concentrating hormone expression in the hypothalamus of broiler chickens

Ádám Simon; József Németh; András Jávor; István Komlósi; Péter Bai; János Oláh; Bela Juhasz; Rita Kiss; Zoltán Szilvássy; Levente Czeglédi

We aimed to quantify the gene expression changes of the potent orexigenic melanin-concentrating hormone (MCH) in chicken (Gallus gallus) hypothalamus with quantitative real-time polymerase chain reaction (qPCR), and for the first time determine peptide concentrations with a novel radioimmunoassay (RIA) under different feeding status. Three different experimental conditions, namely ad libitum feeding; fasting for 24 h; fasting for 24 h and then refeeding for 2 h, were applied to study changes of the aforementioned target and its receptor (MCHR4) gene expression under different nutritional status. The relative changes of MCH and MCHR4 were also studied from 7 to 35 days of age. Expression of PMCH and MCHR4 along the gastrointestinal tract (GIT) was also investigated. We found that expression of both targets was significant in the hypothalamus, while only weak expression was detected along the GIT. Different nutritional states did not affect the PMCH and MCHR4 mRNA levels. However, fasting for 24 h had significantly increased the MCH-like immunoreactivity by 25.65%. Fasting for 24 h and then refeeding for 2 h had further significantly increased the MCH peptide concentration by 32.51%, as compared to the ad libitum state. A decreasing trend with age was observable for both, the PMCH and MCHR4 mRNA levels, and also for the MCH-like immunoreactivity. Correlation analysis did not result in a significant correlation between MCH peptide concentration and abdominal fat mass in ad libitum fed birds. In conclusion, MCH peptide concentration altered in response to 24 h fasting, which indicated that this peptide may take part in feed intake regulation of broiler chickens.


Acta Veterinaria Hungarica | 2017

X- and Y-chromosome-specific variants of the amelogenin gene allow non-invasive sex diagnosis for the detection of pseudohermaphrodite goats

Renáta Fábián; András Kovács; Viktor Stéger; Krisztián Frank; István Egerszegi; János Oláh; Szilard Bodo

The Polled Intersex Syndrome (PIS) is responsible for the absence of horns in homozygous and heterozygous goats causing a female-to-male sex reversal in the homozygous polled genotypic female (XX) goats. A simple and efficient non-invasive method was elaborated to detect the genotypic sex from hair and faecal samples using a pair of primers to amplify the X- and Y-linked alleles of the amelogenin gene. The PCR products were easily distinguishable using agarose gel electrophoresis: we detected an X-specific single band in samples originating from healthy phenotypic females and double (X- and Y-) bands in samples from males. The new PCR method is applicable for diagnosing the sex of PIS-affected animals already as newborn kids, in contrast with the phenotypic findings appearing only after puberty, and thus it may replace the cumbersome chromosome investigations.


Scientific Papers: Animal Science and Biotechnologies | 2014

The protective effect of antioxidants on liquid and frozen stored ram semen - review.

Csilla Budai; István Egerszegi; János Oláh; András Jávor; András Kovács


Scientific Papers Animal Science and Biotechnologies | 2013

Performance and Adaptability of the Dorper Sheep Breed under Hungarian and Romanian Rearing Conditions

Csilla Budai; Dinu Gavojdian; András Kovács; Felician Negrut; János Oláh; Ludovic Toma Cziszter; Szilvia Kusza; András Jávor


Journal of Animal Physiology and Animal Nutrition | 2018

Reference gene selection for reverse transcription quantitative polymerase chain reaction in chicken hypothalamus under different feeding status

Ádám Simon; András Jávor; Péter Bai; János Oláh; Levente Czeglédi


Scientific Papers: Animal Science and Biotechnologies | 2013

Influence of birth type and sex on the growth performance of Dorper lambs.

Nikolett Csizmár; Zsolt Györi; Csilla Budai; János Oláh; András Kovács; András Jávor


Archive | 2018

Előzetes adatok a White Suffolk juhfajta hazai eredményeiről

János Oláh; István Monori; Levente Lajkó; Nóra Vass; Szilard Bodo; András Jávor; Mariann Tóth; István Egerszegi


Acta Veterinaria Brno | 2015

Bacterial overgrowth can be detected by breath hydrogen measurement before clinical manifestations in suckling lambs

András Jávor; Anikó Nagy; Ágnes Papp-Bata; Nóra Vass; János Oláh; Zoltán Csiki

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Nóra Vass

University of Debrecen

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Anna Pécsi

University of Debrecen

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