The objective of the study was to vitrify mouse embryos with the cryoloop technology using a new combination of vitrification mediums. Embryos were exposed to a 2- step loading of CPA, ethylene glycol and propylene glycol, before being placed on the surface of a thin filmy layer formed from the vitrification solution in a small nylon loop. Afte...r warming, the CPA was diluted out from the embryos by a 3-step procedure. Our data show that a high percentage of embryos survived (92.7%) vitrification in the mixture of EG and PG combined with cryoloop carrier and developing normally (89.1%) in vitro after thawing.
The viewpoint of the recent cryopreservation techniques (CT) suggests the use of a reduced volume of cryopreservation solution, high concentration of cryoprotectants and ultra-rapid cooling and warming rates help to reduce cryo-injury and maximize the viability of the preserved animal genetic resources (AnGR). The CT had now become widely a...ccepted as one of the best methods of choice for the ex-situ conservation of AnGR due to its high success rate recorded and no-invasive nature as compared to the conventional slow rate freezing (CSRF). Rapid advances and wide acceptability of the use of assisted reproductive technologies (ART’s) particularly artificial insemination (AI) in animal breeding had resulted in a greater loss of a large number of good quality genes in virtually almost all the native breeds of animals across the globe. Small ruminant (SR) animals are not an exception in such present predicaments situation of erosion and dilution of the valuable AnGR among the native breeds. As a result of this, 148 and 16 breeds of sheep and goats respectively have already become extinct in Europe and the Caucasus. In view of the aforementioned situation, the present review aimed at exploring some of the current states of development, roles played and potentials of CT in the conservation of SR genes and genome for the immediate and future breeding purposes for sustainable development. It basically covers; animal genetic resource, the need to conserve AnGR, tools for ex situ in vitro conservation of AnGR and recent developments in breeding and cryopreservation of SR AnGR.
Cryopreservation is playing a pivotal role in ex-situ gene conservation of AnGR. Decline in genetic diversity among SR breed population was high in Europe and the Caucasus. There is therefore, need for improvent on current stringent measures on conservation of AnGR in this region of the world.
The aim of our examination was to detect the puberty of the Hungarian Merino and its hairsheep crossbred ewes, and also to determine their average conception rates after having ram exposed in May and June. Hormon diagnostation was used to evaluate the exact date of the very first ovulation. Ultrasound technique was used for checking the concept...ion rates of ewes. The pregnancy detection was applied after a month of the date of taking off the ram.
We evaluated the ages of ewes at puberty. Statistical deviation and standard error were calculated. The results proved the Hungarian Merino x Somali (N=10), ((x ± s) = 173 ± 43) and also the Hungarian Merino x Barbados Blackbelly crossbred genotypes (N=7), ((x ± s) = 186 ± 19) have their puberty much earlier as compared to the fullbred Hungarian Merino ewes (N=10), ((x ± s) = 231 ± 95). We experienced the highest conception rate in the group of the (Hungarian Merino x Somali) F1 ewes after exposing the ram in the „out-of season” period of time.
Semen of 10 Tsigai,3 Prolific Merino and 7 Barbados Blackbelly rams was taken in January, out of the season. Split samples of the diluted semen samples were kept at 23, v.s. 8oC and their motilitywas evaluated daily for 3 days by subjective microscopic investigation. The ratio of motile spermatozoa was strongly decreased during the f...irst day, later the motility rate was sinking more slowly. It could be stated by multivariance analysis that the motility value of diluted semen of Prolific Merino rams was higher and showed a slower reduction as compared to the other two breeds. The decrease of the motility rates was slower at 8oC than at 23oC.
Aim of our study was the optimization of a DNA method, that is appropriate for reliable, low cost identification of animal species in milk and dairy product (cheese) and to determine the ratio of species. Mitochondrial DNA was used in our work to analyse buffalo/cow milk mixtures contained different ratio of bovine milk such as 0.1%, 0.5%, 1%, ...1.5%, 2%, 5%, 10%, 15% (v/v%). Buffalo cheese were produced using buffalo and cows milk (0%, 2%, 5%, 10%, 15% – v/v% cows milk in buffalo milk). In case of milk mixtures, using species specific primers, the PCR assay showed a 0.5 v/v% detection limit. Cattle, in the buffalo/cows milk 99.9/0.1 v/v% mixture, was not detectable. The identification of buffalo and cows DNA in cheese was successful. The intensity of eletroforetic PCR fragment indicated the increase of cow milk ratio in milk and cheese samples as well.
The possibilities of examination the growth of fish species are verry difficult, and much of methods are oblique. With the weather loach is the work especially complicated through the small scales. Till now the growth of weather loach is in Hungary unexamined.
We applied self developed catch method in three explored channel. The length... and weight measured on the fishes alive, as well the sexing. We analysed the datas with Bertalanffy-method.
The growth of the fishes is different, but the growth of the body length was nearly the same in the three channels. The one year old fishes can growth to a maximum of 130-140 millimeters, the two years old fishes can growth to maximum of 180-190 millimeters. Longer fishes by 180-190 millimeters are 3 or more years old. The data of sex-ratio is deviant than the literature wroted. The fish from Fényes are growing faster, than the others. This species can be 190-200 millimeters long after 2 years from birth. It is a very fast growing.
Success of the embryo transfer programs is affected by many factors (breed, type, season, treatment). We assume, that periferical blood level of some metabolic hormones (IGF-1, thyroid hormones, leptin, insulin) affects the success of superovulation and ET. According to our results, there is a
significant difference between the in and out of... season periferial blood level of IGF-1 and insulin. Furthermore, decrease in the periferic blood levels of IGF-1 and insulin is less drastic in the pregnant recipients.
The bevahiour of Babolna Tetra, Ile de France and Suffolk rams was studied at semen collection by artificial vagina. The sequence of rams coming out of the group to the place of semen collection and the number of jumpings needed to ejaculation were observed. It was investigated if there were changes in these characters at different occasions, a...nd did they show connection to the body condition. The number of jumpings before ejaculation was different in the different breeds. Semen was taken at the first jump from 63% of the Suffolk, 56% of the Babolna Tetra and 55% of the Ile de France rams. There was no early ejaculation at the Ile de France, but it was common among the Suffolk rams. The greatest changes in the jumping order between different semen collections were observed in the Babolna Tetra breed. There was a medium correlation in the Suffolk breed between the jumping order and body condition in the autumn and spring, which was tight and significant in winter.