Comparative morphology of the cerebellum of the seal (Pinnipedia, Mammalia)]

The work describes the anatomical structure of the cerebellum of the caspian seal (Pusa caspica Gmelin) and Greenland seal (Pagophoca groenlandica Erxleben). The shape of the cerebellum, the disposition of the main lobes and convolutions are characterized. The schemes of three projections of the cerebellum of both species are presented. The figures of the cerebellum size, its absolute and relative weight and the surface of the cerebellum and its portions in seals have been obtained. The well-developmed flocculo-nodular portions and paraflocculuses and relatively poorly developed lobulus paramedianus are pointed to be one of the characteristic features of the structure of the seal cerebellum. An attempt is made to explain great dimensions of the flocculo-nodullar portion and paraflocculuses by specific features of the seal locomotion in water.     

Lymphosarcoma in a sea otter (Enhydra lutris)

Lymphoblastic lymphosarcoma involving the mesenteric lymph node and thymus was discovered in a 4 yr old male sea otter (Enhydra lutris). Diagnosis was based on gross and light microscopic studies. The cause of this neoplasm was not determined. This is the first case of lymphosarcoma reported in sea otters.     

Fatty-acyl esters of retinol (vitamin A) in the liver of the harp seal (Phoca groenlandica), hooded seal (Cystophora cristata), and California sea lion (Zalophus californianus).

The fatty-acid composition of retinyl esters in the livers of two species of phocid seal, the harp seal (Phoca groenlandica, n = 20) and the hooded seal (Cystophora cristata, n = 15), and one species of otariid seal, the California sea lion (Zalophus californianus, n = 6), was determined. Vitamin A ranged in concentration from 4 to 1024 nmol retinol/g liver for the phocids and from 381 to 979 nmol/g liver for the otariids. In most of the livers, retinyl palmitate was not the principal ester, and the palmitate + stearate + oleate trio of retinyl esters represented less than 50% of the total. In all samples, the retinyl esters contained 20:1, 20:4, 20:5, and 22:6 in unusually large amounts. Retinyl esters tended to be richer than whole-liver lipids in 20:5 + 22:6, whereas whole-liver lipids were richer in 18:0 and 18:2. Therefore, the pool of acyl donors used for the esterification of retinol may be distinct from that used for other lipids. Birth-to-weaning changes were seen only in the harp seals. In the pups, the hepatic vitamin-A concentration increased 454%, while the proportion of 18:0 and 20:1 in the retinyl esters rose and that of 14:0 + 16:1 and 20:4 fell. Concomitantly, in their mothers, the proportion of 20:4 increased but that of 16:0 and 18:0 decreased.     

Preparation and characterisation of gelatine from the skin of harp seal (Phoca groendlandica)

This paper describes a method for extraction of gelatine from the skin of harp seal at mild acid conditions and gives a chemical and physical comparison of this gelatine with other mammalian and cod-skin gelatines. As compared to the wet weight of unhaired skin, a recovery of 11% dry gelatine was achieved after acid treatment and a two step water extraction at 60 and 75 degrees C. The chemical and physical properties of the gelatine were similar to the properties of commercial gelatines made from bovine and porcine skin, but significantly different from the properties of Atlantic cod-skin gelatine. The results indicated that seal skin gelatine can be used as a substitute for standard commercial gelatines for food technology applications.     

Locomotory activity of captive Cryptomys hottentotus, (Mammalia: Bathyergidae), a fossorial rodent

Locomotory activity of six mole-rats kept singly and in various sized groups was monitored for a total of 1728 hours by use of photocells, event recorder, and a 21 metre long, transparent burrow system. Movement in tunnelways was recorded for all hours of a 24 hour period. Locomotory activity for individuals and a two member group average14–24% of the total time, while a four member group averaged 57% of the total time. Approximately five rest periods per day averaged 50 minutes duration each. The effects of social isolation, burrow length, diet, and individual variation on locomotory activity of fossorial mammals are discussed.