Nursing parameters in captive killer whales (Orcinus orca)
Publication Type: |
Journal Article |
Year of Publication: |
1999 |
Authors: |
Steven T. Clark, Daniel K. Odell |
Publication/Journal: |
Zoo Biology |
Publisher: |
Inc., John Wiley & Sons |
Keywords: |
captive-born cetaceans, lactation, reproduction |
ISBN: |
1098-2361 |
Abstract:
Abstract 10.1002/(SICI)1098-2361(1999)18:5<373::AID-ZOO2>3.3.CO;2-4 We examined nursing behaviors for a population of captive-born killer whales (four females, three males) at SeaWorld parks from birth until 90 days of age. Nursing parameters examined included cumulatives of suckles per day, bouts per day, and suckle duration (seconds) per day. Daily cumulatives of all nursing parameters peaked within the first 2 days after birth then decreased through time. For the ages from birth until 42 days, data were converted using loge-loge transformations to allow linear regression modeling. Since these parameters were characterized by autocorrelation, bootstrapping was used to obtain parameter estimates for comparisons between sexes and cow parity. Both males and females, as well as calves born to primiparous and multiparous cows, exhibited similar nursing patterns. However, there were statistically significant differences (α < 0.05) between the regression equations among most of the nursing parameters examined. Cumulative frequencies and amounts from birth through 42 days of age for all nursing parameters were examined. Means were statistically similar (α > 0.05) between genders (means[sd] for males and females, respectively; suckles 3,772.7[412.4] and 3,276.3[1,226.5]; bouts 1,238.3[189.0] and 1,103.3[96.4]; suckle duration [seconds] 28,990.7[5,861.9] and 29,233.0[5,255.0]) and cow parity (means[sd] for primiparous and multiparous, respectively; suckles 4,459.0[606.7] and 3,101.0[753.8]; bouts 1,240.0[243.3] and 1,129.6[116.2]; suckle duration [seconds] 32,415.0[5,212.8] and 27,814.8[4854.5]). Equal amounts of nursing occurred from both left and right mammary glands for the 42-day time period (means[sd] [seconds] for left and right, respectively; 13,800.4[2,787.0] and 15,328.7[2,471.0]; P = 0.30). Zoo Biol 18:373–384, 1999. © 1999 Wiley-Liss, Inc.