The Effect of Long Term Starvation on Galanin, Leptin, Thyroid Hormones, Insulin, Prolactin, Growth Hormone, Ghrelin and Factors Involved in Energy Metabolism in Adult Goats

Öz

Some hormonal disturbances have been demonstrated in starvation, but in ruminants such as goats, the role of galanin in adaptation to starvation or endocrine functions is not well studied. The present study was conducted to assess the effect of long term starvation on galanin, leptin, thyroid hormones, insulin, prolactin, growth hormone, ghrelin and factors involved in energy metabolism including HDL, Cholesterol, β-hydroxybutyrate, glucose, NEFA, TG and VLDL concentrations in adult goats. Eight non-lactating non-pregnant goats aged 4-5 years and BCS 3 were randomly divided to control and test groups. The animals were trained to eat their daily forage ration during a 10 day period. The experimental procedure was applied for 20 days, during which control group received 120% of maintenance energy, while the test group was supplied with 80% of maintenance energy for the first 10 days and with 40% of maintenance energy for another 10 days. Blood samples were collected at day 10 of training and 2, 4, 10, 12, 14 and 20 days after beginning of starvation. Blood parameters were measured according to standard procedures. No significant difference was observed in the concentrations of cholesterol, fT3, T4, T3, growth hormone, NEFA, insulin and ghrelin between control and test groups (P=0.05). There was significant difference in galanin, leptin, fT4, HDL, glucose, TG, VLDL and prolactin concentrations between control and test groups (P=0.05). Control of energy balance and the role of galanin in adaptation to long starvation or endocrine functions in goat are different from other species.

Anahtar Kelimeler

• Long term starvation, galanin, leptin, biochemical parameters, energy metabolism, goat

Erişkin Keçilerde Uzun Süreli Açlığın Galanin, Leptin, Tiroid Hormonları, İnsulin, Prolaktin, Büyüme Hormonu, Grelin ve Enerji Metabolizması ile İlgili Faktörler Üzerine Etkisi

Öz

Açlık durumunda bazı hormonal bozukluklar gösterilmiş, ancak keçiler gibi geviş getiren hayvanlarda galaninin açlığa ya da endokrin fonksiyonlara uyumu iyi araştırılmamıştır. Mevcut çalışma erişkin keçilerde uzun sureli açlığın galanin, leptin, tiroid hormonları, insulin, prolaktin, büyüme hormonu, grelin ve HDL, kolestreol, β-hidroksibutirat, glukoz, NEFA, TG ve VLDL konsatrasyonları da dahil olmak üzere enerji metabolizması ile ilgili faktörler üzerine olan etkisini değerlendirmek için yürütülmüştür. 4-5 yaşları arasında, süt emzirmeyen ve gebe olmayan vücut kondisyon skoru 3 olan sekiz keçi rastgele olarak kontrol ve test gruplarına ayrıldı. Hayvanlara 10 günlük bir süre boyunca yemleme programına alıştırıldı. Deneysel işlem 20 gün uygulandı; bu süre içinde kontrol grup idame enerjisinin %120’sini aldı, test grubuna ise ilk 10 gün içinde idame enerjisinin %80’i verildi; diğer 10 gün boyunca ise idame enerjisinin %40’ı verildi. Yemleme programına alıştırmanın 10. gününde ve açlık başlamasından sonraki 2, 4, 10, 12, 14 ve 20. günlerde kan örnekleri alındı. Kan parametreleri standart işlemlere göre ölçüldü. Kontrol ve test grupları arasında kolesterol, fT₃, T₄, T₃, büyüme hormonu, NEFA, insulin ve grelin yönünden bir farklılık görülmedi (P=0,05). Kontrol ve test grupları arasında galanin, leptin, fT_4, HDL, glukoz, TG, VLDL ve prolaktin konsantrasyonlarında anlamlı farklılıklar vardı (P=0,05). Keçilerde uzun sureli açlığa uyumda galaninin rolü ve enerji dengesi kontrolü ya da endokrin fonksiyonları diğer türlerden farklılık göstermektedir.

Anahtar Kelimeler

• Uzun süreli açlık, galanin, leptin, biyokimyasal parametreler, enerji metabolizması, keçi

Kaynakça

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