Venom yields of the Philippine cobra, Naja naja Philippinensis

Data on venom yields of 150 cobras (Naja naja philippinensis) gave an overall average venom yield per cobra per extraction (AVY/C/E) of 0.33 ml or 70.14 mg and an overall average total lifetime venom yield per cobra ( ATLVY/C) of 2.23 ml or 527.77mg for the fresh and corresponding dried venom, respectively.The ATLVY/C were greater at schedule every 14 days than those at schedule every 7, 21, or 28 days.The all-male groups gave bigger yields than the corresponding allfemale groups.The AVY/C/E in the former increased as the intervals between extractions lengthened.In the latter the reverse was observed.The solid content of the venom does not appear to be affected by either sex, time of the year, or schedule of collection, but the serial records of extractions show a tendency for this to gradually decline with time.Venom extraction at close intervals resulted in a marked decline of the solid content, the rate of reduction becoming more marked in direct proportion to frequency of extraction.The data on AVY/C/E of several groups indicate a general tendency for this to decline with time.