TITLE:
Growth and Reproductive Activity of a Captive Female Harbour Porpoise (Phocoena phocoena) from Japanese Water
AUTHORS:
Kazutoshi Arai, Gen Nakamura, Yoshiaki Maeda, Etsuko Katsumata, Hiroshi Katsumata, Kazuyoshi Taya, Hidehiro Kato
KEYWORDS:
Harbour Porpoise, Female, Growth, Reproductive Activity, Japanese Water
JOURNAL NAME:
Open Journal of Animal Sciences,
Vol.7 No.3,
July
14,
2017
ABSTRACT: This report describes growth and annual reproductive
cycle of female harbour porpoise (Phocoena
phocoena) rescued from Japanese water in 2007. The maximum body
length was 179 cm and body weight was 69.8 kg. The average daily food
consumption was 7.0 kg (ranging 3.7 - 9.9 kg), 11.8% of the body weight. In
this report, the porpoise was kept in 17 °C water annually and the blubber thicknesses
showed almost constant throughout the year (average 18 mm, range 13 - 22 mm).
Therefore, we added new evidence to this hypothesis by showing that body weight
and the blubber thickness do not fluctuate seasonally in fixed water
temperature. Serum progesterone level of the female showed five peaks from
September to November, and each cycle lasted the average of 20.5 days. Such
result indicates that harbour porpoise exhibits seasonal polyestrous activity.