The Effect of the Seasons and Sex on the Structure and Activity of the Thyroid Gland of Dromedary Camels

(Saeed Yassin Al-Ramadan)

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Abstract

The dromedary camels are exposed to extreme weather conditions that affect their metabolic performance. The current research aims to study the effects of seasons and sex on the histological features of camel thyroids and T3, T4, and TSH levels. Twenty-eight adult camels were used in this study. The height of the follicular epithelium, the number of the follicles/field, and the diameter of the follicles showed seasonal variations (winter 10.5±0.46 µm, 4.79±2.12, 122±7.0 vs. summer 7.47±0.32 µm, 4.65±2.23, 130±10.0 µm). These parameters were measured in different sexes and found to be (male 9.2±0.66 µm, 5.47±2.0 follicle/field, 119±6.0 µm vs. female 8.4±0.69 µm, 3.16±1.2 follicle/field, 146±17.0 µm). Seasonal differences at the hormonal level were (winter T3: 1.14±0.12 ng/ml, T4: 28.87±1.36 µg/dl, TSH: 3.68±28 MIU/ml vs. summer T3: 0.95±0.10ng/ml, T4: 31.91±2.46µg/dl, TSH: 3.47±0.34MIU/ml). Sexual variations were also recorded in these hormones (males: T3: 1.37±0.34 ng/ml, T4: 30.14±2.45 µg/dl, TSH: 2.28±0.35 MIU/ml vs. females: T3: 1.06±0.06 ng/ml, T4: 25.8±2.20µg/dl, TSH: 3.93±0.20 MIU/ml). In conclusion, this study sheds some light on aspects of the changes in camel thyroids. There is still much to be done to discover more characteristics of this animal and how it adapts to the desert environment.

KEYWORDS
Camel, thyroid gland, thyroid stimulating hormone triiodothyronine and thyroxine

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References

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