The baleen whales (suborder Mysticeti) are filter-feeders that reach gargantuan size. At 100,000 kg or more, a fully-
grown blue whale attains the largest mass of any animal. This large mass allows females to mobilize vast quantities of nutrients from body reserves during lactation.[4,9] Most of the very large species, such as gray, humpback, fin, and blue whales, migrate back and forth between high-latitude/polar regions, where they feed, and warm temperate/tropical regions, where they give birth and lactate but fast or feed little. In blue and fin whales, the calves gain about 50 80 kg/d, ingest milk containing 32 35% fat, and are weaned at 6 7 months (Table 1). This short lactation, relative to body size, minimizes the time spent on breeding grounds where food resources are sparse. The amounts of milk (220 kg/d) and milk-energy (4000 MJ/d) that blue whales are estimated to produce far surpass those of other mammals, but in relation to maternal metabolic size, the daily output of milk-energy (0.72 MJ/kg075/d) is not remarkable, resembling that of many terrestrial mammals.
Was this article helpful?
If Pregnancy Is Something That Frightens You, It's Time To Convert Your Fear Into Joy. Ready To Give Birth To A Child? Is The New Status Hitting Your State Of Mind? Are You Still Scared To Undergo All The Pain That Your Best Friend Underwent Just A Few Days Back? Not Convinced With The Answers Given By The Experts?