The Effect Of Calcium Antagonists On Pulmonary Artery Pressure And Ascites Syndrome In Broiler Chickens

The experiment was to evaluate the effects of Calcium Antagonists on Pulmonary hypertension (PH) and the mechanism of the Calcium Signal in PH in broilers. 200 AA male commercial broiler chickens were randomly divided into four groups on 15-day-old, normal ambient temperature group (19-24℃) (NT); three low temperature groups (9-11℃), including blank group (LT), Nifedipine group (p.o.)(Nif), Verapamil group (p.o.)(Ver), 50 each group. 10 birds were selected from each group at the age of 28, 36 and 48 days for measuring the Pulmonary Artery Contract Pressure (PACP), Pulmonary Artery Stretch Pressure (PASP), Right Ventricular Systolic Pressure (RVSP), Right Ventricular Diastolic Pressure (RVDP), Maximum change ratio of Right Intraventricular Pressure (RV±dp/dt max), the Packed Cell Volume (PCV), the Ascites Heart Index (AHI) and the incidence of AS. The results were as follows:1. The mPAP of LT on 28 and 36 days old(3.4±0.7kPa, 3.4±1.3kPa) were higher than that of NT ( 2.2±0.7kPa, 1.7 ±0.1kPa) (P<0.05), respectively;The mPAP of LT in 44 days old(3.7 ±0. kPa) was Significantly higher than that of NT(2.7 ±1.2kPa) (P<0.01).2. The mPAP of Nif were decrease than that of LT on 28 and 36 days old(P>0.05); The mPAP of Nif 44days old(3.7±0.7kPa)was Significantly lower than that of LT(2.4±0.2kPa) (P<0.01). Incidence of AS of Nif was low than that of LT (P>0.05).3. The mPAP of Ver on 28 and 36 days old(1.8±0.8kP and 1.3±0.3kPa)was lower than that of LT(3.4±0.7kPa and 3.4±1.3kPa), respectively(P<0.05). The mPAP of Ver was Significantly lower than that of LT on 44 days old (P<0.01). Incidence of AS of Ver was lower than that of LT (P<0.05).Ver and Nif decrease mPAP and incidence of AS, We can get a conclusion that calcium signal play an important action in the development of PH and occurrance of AS.