Serum Profile of Thyroid Hormones from Birth to Puberty in Buffalo Calves and Heifers

In tropical countries, unlike other dairy animals the buffalo presents the farmers with problems of growth and late maturity, which reduces their total life time productivity. The exotic buffalo heifers have been reported to reach puberty at the age of 15 - 16 months and 15 - 17 months in Italy and Egypt, respectively. In contrast, our indigenous buffalo breeds, namely, Nili-Ravi, Surti and Mehsana reach puberty at an age of 26, 28.2 and 30.1 months, respectively. Murrah buffaloes exhibit delayed maturity even more, which limits their productive life. The study investigated the serum thyroid patterns in female Murrah buffalo calves and heifers from birth to puberty. TSH concentration did not differ and remained almost the same from birth to 4 - 6 mths. The TSH then gradually increased and reached a highest value at 24 - 30 mths. The TSH concentration recorded at 21 - 24 mths and 24 - 30 mths i.e. at the age of attaining the puberty, was about 3 - 4 times higher than recorded at birth. The T3 concentration recorded at 0 - 7 days of age was significantly higher than recorded for other age groups, except at 18 - 21 mths, 21 - 24 mths and 24 - 30 mths. The T3 concentration did not exhibit specific trend during the ages 16 days - 1 mth to 15 - 18 mths. The highest T4 concentration was recorded in 0 - 7 days old buffalo calves. The concentration decreased to lower value at 1 - 2 mths. The T4 concentration from 2 - 4 mths of age increased significantly and the values remained almost similar with minor fluctuations upto 24 -30 mths. The T4 : T3 ratio recorded at different ages did not exhibit specific trend

Anti-Müllerov hormon: novi pristup procjeni plodnosti u goveda – pregledni rad

The anti-Müllerian hormone (AMH) enhances fertility in cattle and hence used as a fertility marker. AMH is produced by granulosa cells of all primordial, primary, secondary follicles, and antral follicles up to 4-5 mm diameter, whereas AMH production decreases once antral stage follicles reach the 4-5 mm stage. There is an individual variation in antral follicle count (AFC) and AMH concentration. One-time determination of AMH concentration will help predict the animals’ reproductive performance at the heifer stage. In turn, it will help to cull those animals with low reproductive potential. There is no significant fluctuation in the AMH concentration during the estrous cycle, and hence it can be determined at any stage of the estrous cycle. This review explores the potential of AMH as a fertility marker and its association with the antral follicle population (AFP) as AMH can be an effective segregative tool to screen low, average or high fertility future performance in cattle.Anti-Müllerov hormon (AMH) poboljšava plodnost u goveda zbog čega se upotrebljava kao marker za to važno svojstvo. Proizvode ga granulozne stanice svih primordijalnih, primarnih i sekundarnih folikula te antralnih folikula promjera 4–5 mm. Nakon što folikuli u antralnoj fazi dosegnu 4–5 mm, njihova se proizvodnja smanjuje. Postoje i individualne varijacije u broju antralnih folikula (AFC) i koncentracije AMH-a. Jednokratno određivanje vrijednosti AMH-a pomoći će u predviđanju reproduktivne sposobnosti junica, također i pri izlučivanju životinja s malim reproduktivnim sposobnostima. Kako nema znakovite fluktuacije u vrijednosti AMH-a za vrijeme estrusa, ta se vrijednost može odrediti u bilo kojoj fazi estrusnog ciklusa. U ovom su radu analizirani potencijal AMH-a kao markera plodnosti i njegova povezanost a antralnim folikulima (AFP) s obzirom na to da AMH može biti učinkovit alat u praćenju rezultata niske, prosječne i visoke plodnosti u goveda