Original scientific paper
INFLUENCE OF INDUCED MOLTING ON HORMONAL STATUS OF AGED LAYING HENS
Natasha Gjorgovska
; PSi Institute of Animal Science, Skopje, Macedonija
Kiril Filev
; Faculty of Agricultural Sciences and Food, Skopje, Macedonija
Rossitza Konakchieva
; Institute of Biology and Immunology of Reproduction "Acad. K. Bratanov", Sofia, Bulgaria
Abstract
Physiological mechanisms of reproduction, during induced molting, have not been investigated enough. From the investigations so far it is known that induction of molting with total fasting initiates drastic decrease of body weight, decrease of gonadotropic and seks hormones concentration in plasma and increase of the thyroid hormone concentration. The aim of this investigation was to establish changes of the level of foliclestimulating hormone (FSH), luteinizing hormone (LH) and progesterone in two genotypes of hens: ISA Brown, 88 weeks old and Hisex Brown, 91 weeks old in specific points of molting period. From the obtained results it can be seen that hormonal status of hens significantly changed because the FSH concentration in blood plasma during the preparing period for molting was 60.48 ng/ml, 62.36 ng/ml and 76.26 ng/ml for third, first and second group. After the period of stress it was significantly ecreased: 23.38 ng/ml, 25.16 ng/ml and 44.59 ng/ml, and in the second egg laying cycle the concentration was stabilized and reached in 91.36 ng/ml in group 3 (Hisex Brown hens), 45.12 ng/ml in group 2 and 64.26 ng/ml in group 1 (ISA Brown hens). Concentration of LH was also changed because during the preparing period it was: -16.88 ng/ml, 11.16 ng/ml and 23.85 ng/ml, in groups 1,2 and 3; during the stress period:-2.08 ng/ml, 13.96 ng/ml and 9.90 ng/ml in groups 1, 2 and 3. During the laying period it increased because in the time of maximum egg production it was 27.50 ng/ml, and 21.92 ng/ml, (first and second group)(ISA Brown), but the highest concentration was measured in hens from group 3, 37.35 ng/ml (Hisex Brown). Progesterone in blood plasma during the preparing period in group 1 was 167.5 pg/ml, in group 2, 49.6 pg/ml (ISA Brown), but in group 3 it was 94.8 pg/ml (Hisex Brown). At the end of the stress period there was significant decrease and in group 1, it was 0, in group 2, 19.2 pg/ml, and group 3, 25.6 pg/ml. During maximum egg laying, the concentration of progesterone increased and it was: -135.3 pg/ml in group 3 (Hisex Brown), and 22.64 and 41.4 pg/ml in group 1 and 2 (ISA Brown).
Keywords
artificial molting; hormonal status; laying hens
Hrčak ID:
26996
URI
Publication date:
10.3.2008.
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