Author/Authors :
Peksa، Zdenek نويسنده University of South Bohemia, Faculty of Agriculture, Department of Veterinary Sciences and Quality of Products, Studentsk? 13, 370 05 ?eské Bud?jovice, Czech Republic , , Travnice، Jan نويسنده University of South Bohemia, Faculty of Agriculture, ?eské Bud?jovice, Czech Republic , , Dusova، Hana نويسنده University of South Bohemia, Faculty of Agriculture, ?eské Bud?jovice, Czech Republic , , Konecny، Roman نويسنده University of South Bohemia, Faculty of Agriculture, ?eské Bud?jovice, Czech Republic , , Hasonova، Lucie نويسنده University of South Bohemia, Faculty of Agriculture, ?eské Bud?jovice, Czech Republic ,
Abstract :
The study presents an evaluation of morphological and histometric parameters of the thyroid
gland of slaughtered cattle (29 cows, 10 bulls, 7 heifers and 4 calves). The thyroid gland of
bulls contained 34.7% of large follicles while their content in cows and heifers was 32.6% and
only 19.2%, respectively. The average follicle length was 162.0±19.8 ?m in bulls, 153.5±24.8
?m in cows and 122.4±10.1 ?m in heifers. The highest thyreocytes were found in heifers and
bulls (9.45±1.17 and 9.42±1.50 ?m, respectively) and the lowest in cows (8.46±2.13 ?m). A
positive relationship was determined between the iodine content of the thyroid gland and
the percentage of large follicles (r = 0.55) while the relationship between iodine content and
thyreocyte height was negative (r = –0.21). In the thyroid gland of older cows medium and
large follicles with low cubic to flat thyreocytes were dominant. Some follicles contained
necrotic thyreocytes and the cytoplasm contained lipofuscin. The results suggest the influence
of an increased iodine content in the thyroid gland on follicle size and thyreocyte height
