As a part of an ongoing long-term study on the biology of pack-ice seals in Antarctica, we had the opportunity to collect lice from Weddell seals (Leptonychotes weddelli). We did not find the original description of this host-parasite association. Antarctophthirus ogmorhini had previously been reported as a parasite for the Weddell seal, but the information is, to a certain extent, confusing. During the development of the present study, we had access to literature concerning the presence of A. ogmorhini on this host, which, to our knowledge, was not determined in any of the previous works on this species. We compared lice collected from Weddell seals with A. ogmorhini obtained from the type host, the leopard seal (Hydrurga leptonyx), and we found that both species can be distinguished. The main differences are the characteristic pattern of chaetotaxy in the dorsal side of the head in lice from Weddell seals, the size and form of the pseudopenis, and the distribution and size of the fringe of setae surrounding the genital opening. Considering the conservative morphology, and ecological and evolutionary features of sucking lice, we proposed that lice from Weddell seals constitute a new species. In the present work, we described and illustrated adults of this new species collected from Weddell seals during the austral summer of 2014 at the Danco Coast, Antarctic Peninsula.

The Weddell seal (Leptonychotes weddellii Lesson, 1826) has in common with other antarctic phocids, a lactation characterized by high rates of nutrients and energy transfer. The Study of the variations in the milk composition contributes to the knowledge about this particular model of lactation and allows the acquisition of basic information for veterinary medical studies. The present Study shows the preliminary results of the analyses of the variations in milk Cat and protein levels from four females sampled sequentially along lactation at Laurie island, South Orkney Islands during the 2002 breeding season. Important inter individual variations were observed among the sampled females, but a similar pattern along time which showed: a) an increasing trend for tat levels during the first half of the lactation period (13.04 to 61.25 g 100 g(-1)), and then maintaining high values (41.21 to 48.88 g 100 g(-1)) from this point until the end of suckling, and b) total protein levels fluctuated within a narrow, range (8.10 to 11.74 g 100 g(-1)) along the period. Fat and protein Values are similar to those reported for other phocids, allowing for the rapid growth and the formation of the blubber to protect the pup and assure its survival.

The Weddell seal (Leptonychotes weddellii Lesson, 1826) has in common with other antarctic phocids, a lactation characterized by high rates of nutrients and energy transfer.The study of the variations in the milk composition contributes to the knowledge about this particular model of lactation and allows the acquisition of basic information for veterinary medical studies.The present study shows the preliminary results of the analyses of the variations in milk fat and protein levels from four females sampled sequentially along lactation at Laurie Island, South Orkney Islands during the 2002 breeding season.Important inter individual variations were observed among the sampled females, but a similar pattern along time which showed: a) an increasing trend for fat levels during the first half of the lactation period (13.04 to 61.25 g 100 g -1 ), and then maintaining high values (41.21 to 48.88 g 100 g -1 ) from this point until the end of suckling, and b) total protein levels fluctuated within a narrow range (8.10 to 11.74 g 100 g -1 ) along the period.Fat and protein values are similar to those reported for other phocids, allowing for the rapid growth and the formation of the blubber to protect the pup and assure its survival.

The Weddell seal (Leptonychotes weddellii Lesson, 1826) has in common with other antarctic phocids, a lactation characterized by high rates of nutrients and energy transfer. The study of the variations in the milk composition contributes to the knowledge about this particular model of lactation and allows the acquisition of basic information for veterinary medical studies. The present study shows the preliminary results of the analyses of the variations in milk fat and protein levels from four females sampled sequentially along lactation at Laurie Island, South Orkney Islands during the 2002 breeding season. Important inter individual variations were observed among the sampled females, but a similar pattern along time which showed: a) an increasing trend for fat levels during the first half of the lactation period (13.04 to 61.25 g 100 g -1 ), and then maintaining high values (41.21 to 48.88 g 100 g -1 ) from this point until the end of suckling, and b) total protein levels fluctuated within a narrow range (8.10 to 11.74 g 100 g -1 ) along the period. Fat and protein values are similar to those reported for other phocids, allowing for the rapid growth and the formation of the blubber to protect the pup and assure its survival.