A TOBEC módszer alkalmazhatóságának vizsgálata a tenyésztojások szelekciójában, a tojások keltethetőségének, a naposcsibék életképességének és a brojlerek vágóminőségének javítása érdekében = Examination of usefulness of the TOBEC method in the selection of hen eggs for improving the hatchability, the viability of the chicks and the dressing percentage and meat quality of the broilers

Kutatási programunkban tyúktojások összetételének in vivo vizsgálatával összefüggéseket kerestünk a tojásösszetétel, a keltethetőség, a naposcsibék keléskori súlya, keléskori testösszetétele, kelés utáni növekedése és vágóértéke között. A kísérlet során 1.500 tyúktojás TOBEC vizsgálatát végeztük el, majd a mért ún. E-értékek alapján a két szélső és a középső 15-15%-ot keltetésre kiválogattuk. A keltetés során megállapítottuk, hogy a magas elektromos vezetőképességű tojások szignifikánsan nagyobb mértékben estek ki a kísérletből embrióelhalás miatt, mint az alacsony elektromos vezetőképességűek. A tojásösszetétel és a tojássúly elkülönített hatását elemezve megállapítottuk, hogy azonos tojássúly esetén az E-érték/súly hányados növekedésével, azonos E-érték/súly hányados esetén pedig a tojássúly növekedésével nő a madarak kelési súlya. A kikelt csibék naposkori testösszetételét vizsgálva azt tapasztaltuk, hogy az alacsony elektromos vezetőképességű tojásokból kelt csibék testének szárazanyag-, fehérje- és zsírtartalma is magasabb volt, mint a magas elektromos vezetőképességű tojásokból kelt társaiké. Hathetes életkorban az alacsony elektromos vezetőképességű tojásokból kelt csibék testsúlya mindkét ivarban magasabb volt, mint a magas elektromos vezetőképességű tojásokból kelt társaiké. A 42 napos kori vágáskor a vizsgált testösszetevők súlyában igen, testsúlyhoz viszonyított arányában viszont nem tudtunk szignifikáns különbséget kimutatni a kísérleti csoportok között. | In this project - using an in vivo examination of hen's eggs composition - the effect of egg composition on the hatchability, on the chick's hatching weight, body composition, growth and slaughter characteristics was studied. Altogether 1.500 hens' eggs were measured by TOBEC, and the extreme and average 15-15% were chosen for incubation based on the measured E-values. During the incubation period, it was observed that eggs with high E-value/egg weight ratio fall out in a significantly higher ratio, than eggs with low E-value/egg weight ratio. Examining the separate effect of egg weight and egg composition on the hatching weight, it was established that the increase of E-value/egg weight ratio at the same egg weight, and the increase of egg weight at the same E-value/egg weight ratio resulted in an increase in the hatching weight. It was also established that the dry matter, protein and fat content of the chicks, hacthed from eggs with low electrical conductivity was higher at hatching, than that of the chicks hatched from eggs with high electrical conductivity. At 6 weeks of age the liveweight of chicks hatched from eggs with low electrical conductivity was higher in both sexes, than that of the chicks hatched from eggs with high electrical conductivity. At slaughter - at 42 days of age - significant differences were obtained in the weight of the examined body parts, but no significant effect of egg composition was observed in their ratio to liveweight

A tojásösszetétel, a keltethetőség, valamint a kikelő madarak fejlődése és termelése közötti összefüggések in vivo vizsgálata komputer tomográffal kettőshasznosítású tyúk genotípusokban = In vivo examination of the correlations between hen's egg composition, hatchability and hatched chick's development and production by means of computer tomography in dual-purpose genotypes

A kutatási program keretében kidolgoztuk a tyúktojások CT vizsgálatának metodikáját. Meghatároztuk a legjobban értékelhető felvételek elkészítéséhez szükséges technikai paramétereket és az egyidejűleg vizsgálható tojások számát. A tojások sárgája arányának meghatározásához egy új szoftvert fejlesztettünk, ami lehetővé tette a keresztmetszeti képek gyors és automatikus értékelését. Megállapítottuk, hogy a kisebb sárgája, azaz nagyobb fehérje aránnyal rendelkező tojásokból nagyobb súlyú csibék kelnek mindkét ivarban. A kakasok esetében a nagyobb fehérje arányú tojásokból kelt madarak a testsúlybeli fölényüket a hizlalás végéig megőrizték, míg a jércék kelési súlyában megfigyelt különbségeket a hizlalás végén már nem lehetett kimutatni. A keltetőtojások sárgája aránya szignifikáns hatással volt viszont a jércék testzsírtartalmának nevelés alatti alakulására, ami kihatással volt a későbbi termelésükre. A kutatás során megállapítottuk, hogy a tyúktojások összetétele a CT használatával pontosabban becsülhető, mint a korábban alkalmazott TOBEC módszerrel. A tojások összetétele szignifikáns hatással van a csibék kelési súlyának és testösszetételének alakulására, ami kihatással van a későbbi fejlődésükre és ezen keresztül a termelésükre. Mindezek alapján indokoltnak tűnik a tojásösszetétel in vivo meghatározásának további pontosítása, a tojásösszetétel, a keltethetőség, valamint a kikelő madarak fejlődése és termelése közötti összefüggések további tisztázása érdekében. | In the frame of this research project the methodology of CT examination of hen’s eggs was developed. The optimal technical parameters and the number of simultaneously scanable eggs were determined in order to obtain the best quality CT images for the evaluation. For the fast and automatic determination of yolk ratio a new software was developed. By separating eggs with different predicted yolk ratios it was established that chicks hatched from eggs with low yolk – high albumen – content had higher liveweight at hatching in both sexes. This higher liveweight was also observed at the end of the rearing period in the case of the cocks, but it was not observable in the case of the pullets. However, the yolk content of the eggs had a significant effect on the body fat content of the pullets, which affected the latter production of these birds. During this research work it was also established that the predictability of the composition of hen’s eggs is more accurate by means of the CT than it was formerly by means of the TOBEC method. The composition of the eggs has a significant effect on the liveweight and body composition of the chicks at hatching, which has an effect on their latter development and production. Therefore, based on these results it seems to be necessary to improve the accuracy of the in vivo prediction of egg’s composition in order to clarify the correlations between egg composition, hatchability and hatched bird’s development and production more precisely

SURADNJA IZMEĐU ZEMALJA KVADRILATERALE NA PODRUČJU STOČARSTVA – POČECI I PRESPEKTIVA

In this paper authors reviewed the history of the International Symposium „Animal Science Days” from the beginning up to now. After showing the antecedents of this scientific meeting the places and topics of the former symposiums were demonstrated. After reviewing the development of this event in the last 18 years, collaborations based on the quadrilateral cooperation of the partner universities were demonstrated. As results of these scientific cooperations common publications and also the importance of collaboration in the field of education were evaluated. For further collaborations the fields of common interests and also the internationally available funding were demonstrated. Based on this review it was concluded that “Animal Science Days” symposium contributed significantly to the scientific and educational life of each partner university and the agriculture of the Alps-Adriatic region. The partner universities have further possibilities to extend their collaborations, but a joint lobby for creating new funding possibilities would be a great help for them.U ovom radu prikazana je povijest odvijanja međunarodnog znanstvenog simpozija „Stočarski znanstveni dani” od njegovog početka do danas. Nakon prikaza samog početka ovog simpozija, pobrojana su mjesta i teme kojima su se bavili dosadašnji simpoziji. Također prikazana je suradnja između sveučilišta koja sudjeluju u organizaciji ovog simpozija. Kao rezultat te suradnje objavljen je velik broj zajedničkih publikacija te je naglašeno značenje suradnje u polju edukacije. Također su navedene područja moguće suradnje u budućnosti kao i mogućnosti korištenja međunarodnih izvora financiranja simpozija. na osnovu ovog pregleda može se zaključiti da „stočarski znanstveni dani” daju značajan doprinos poboljšanju znanstvene i nastavne kvalitete na partnerskim sveučilištima kao i poljoprivredi uopće na području regije Alpe –adira. Partnerska sveučilišta imaju mogućnosti proširenja suradnje, ali je pri tome potrebno zajedničko lobiranje za dobivanje sredstava koja bi im pomogla u tome

Comparison of changes in the liveweight and body composition of a newly developed cock line and TETRA-H chicks during the rearing period

The aim of this study was to follow the changes in the liveweight and in the muscle and fat tissue development of 60 chicks originated from a newly developed cock line and from the TETRA-H genotype. Changes in the body composition of these birds were examined by means of computer tomography (CT) in vivo. CT examinations were performed bi-weekly between 4 and 12 weeks of age. Overlapping 8 mm slice thickness measurements were performed covering the whole body of the chicken using a Siemens Somatom Emotion 6 multislice CT scanner. Using the images obtained so-called muscle and fat indices were calculated by determining the ratio of number of pixels with X-ray density values of muscle or fat to the total number of pixels with density values of muscle, water and fat, i.e. the range between -200 to +200 on the Hounsfield-scale. Based on the results, it was established that the liveweight of the chicks in the newly developed cock line was significantly higher at all examination days than that of the TETRA-H chicks. The difference between the two examined genotypes was more than 1 kg in the case of cocks and almost 1 kg in the case of pullets at 12 weeks of age. The ratio of muscle in the bird’s body was higher, while the ratio of fat lower in the case of the TETRA-H chicks at the end of the experiment in both sexes. Based on the results it was concluded that the use of the new cock line for improving the liveweight and meat production of the TETRA-H chicks can cause unfavourable changes in the body composition of the TETRA-H birds, which should be taken into consideration in the breeding programme of the TETRA-H hybrid in the future

In Vivo Examination of Fat Deposition in Growing Rabbits Selected for High and Low Body Fat Content

Pannon White rabbits of average ± 1 S.D. live weight at 10 weeks and of average ± 1 S.D. daily weight gain between 6 and 10 weeks of age were chosen from the experimental stock of our university, and their fat content was determined with an EM-SCAN SA-3152 type small animal body composition analyser (by means of TOBEC method) at 10 weeks of age. Based on the fat content determined, the best and worst 16% of the does and the best and worst 8% of the bucks were chosen and mated with each other (fatty doe with fatty buck and lean doe with lean buck). Their offspring were examined by computer tomography (CT) weekly between 6 and 11 weeks of age. Cross-sectional images (scans) were taken from the scapular arch to the end of the femur on each animal. From this scans the amount of fat was determined and its ratio to the total amount of body was calculated in the scapular, perirenal and pelvic region. In the most cases it was established that the total body fat content and also fat content in the scapular, perirenal and pelvic regions are significantly higher in the offspring of fatty rabbits as in the offspring of non-fatty ones. In the group of non-fatty rabbits the scapular fat increased intensively from the age of 7 weeks. The perirenal fat content began to grow rapidly at 8 weeks in fatty group and at 10 weeks of age in the non-fatty rabbits. Based on the results of this experiment TOBEC method seems to be a useful thing for selecting rabbits based on their body fat content