Southern elephant seals: IgM concentration in milk of cows and serum of their pups

• Published in: Polar biology Vol. 23; no. 10; pp. 671 - 674
• Main Authors: Marquez, Maria E. I., Carlini, A. R., Baroni, A. V., Slobodianik, N. H., Ronayne de Ferrer, P. A., Godoy, M. F.
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01.09.2000; Berlin Springer Nature B.V
• Subjects: Aquatic mammals; Biological and medical sciences; Breastfeeding & lactation; Breeding seasons; Fundamental and applied biological sciences. Psychology; Immunoglobulins; Marine; Marine biology; Marine mammals; Milk; Mirounga leonina; Mother. Fetoplacental unit. Mammary gland. Milk; Pregnancy. Parturition. Lactation; Seals; Vertebrates: reproduction; Scotland; United Kingdom; Great Britain; Europe; Shetland Islands; Antarctica, South Shetland Is., King George I; Mirounga leonina; Carnivora; Lactation; Pinnipedia; IgM; King George Island; Vertebrata; Mammalia; Mother embryonal transfer; Mother young relation; Chemical composition; Polar region; Passive immunization; Breast milk
• DOI: 10.1007/s003000000136
• ISSN: 0722-4060

Serum and milk Immunoglobulin M (IgM) concentrations in 11 mother-pup pairs were measured in southern elephant seals (Mirounga leonina) throughout lactation during 2 breeding seasons at King George Island. Samples were obtained sequentially throughout the suckling period (approximately 23days). The IgM concentration was measured by single radial immunodiffusion on agarose plates. Milk IgM concentrations showed significant differences throughout lactation, with the highest concentrations on the 1st day (x=989.7mg/dL skimmed milk; SD=433.2) followed by a sharp fall during the next 3-6days of the suckling period. The ratio of milk IgM/serum IgM concentrations from mothers ranged from 0.21 to 21.92, with highest values in the 1st day of lactation (x=8.25, SD=5.4) and a decrease in concentration as lactation progressed. This was due to the fact that, throughout lactation, milk IgM concentrations fell while serum IgM values showed an increasing trend. Pups showed the lowest serum IgM values in the 1st day of the suckling period (x=13.0mg/dL, SD=4.3) with an increasing trend as lactation progressed. Despite the high IgM concentrations of milk at day 1 of lactation, by 1week of age pups had serum IgM concentrations only slightly greater than at birth. This suggests that much of this Ig was newly formed and little or no milk IgM was absorbed during the 1st week. Possibly, the function of ingested IgM is to provide local immunity in the pup's gut, during the first few days of postnatal life.[PUBLICATION ABSTRACT]