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Schistosomiasis (mansoni) has a negative impact on serum levels of estradiol, progesterone and prolactin in the female baboon (Papio cynocephalus anubis)
by IO Farah, E Andersson, J Mwenda, E Wango& J Hau

The baboon (Papio cynocephalus anubis) is a well-established discriminative model for human reproduction as well as for studies of human schistosomiasis (mansoni).
The present study examined the impact of experimental Schistosoma mansoni infection on ovarian hormones and prolactin in 28 female baboons (6-8 Kg).
Serum concentrations of estradiol, progesterone and prolactin were recorded 2 and 11 weeks post secondary infection challenge dose (1000 cercariae). Lower than normal levels (serum estradiol < 50 pg/ml, serum progesterone < 1 ng/ml and serum prolactin < 2ng/ml) were found in the circulation, particularly 11 weeks after the challenge, when 20% of the animals had low hormone levels, which may be indicative of an anovulatory ovary.
The results suggest that schistosomiasis may be a contributing factor to reduced fecundity among women in endemic regions.

201
The effects of group-housing and relative weight on feeding behaviour in rats
by Lotta Georgsson, Jennifer Barrett& Dorothy Gietzen

To meet the growing concern for the well-being of laboratory animals, group-housing is now recommended for rats. The aim of the present study was to examine the effects of group-housing and relative weight within the group on feeding behaviour in rats. Studies of the individual feeding behaviour of group-housed animals have been carried out in many farm animals. In these studies, when effects of group-housing and hierarchy on individual feeding behaviour are studied, the results are often confounded by differences in age, body weight, genetic differences and earlier experience of the animal. All these factors were standardised in the present study. The individual meal patterns of 12 male Sprague-Dawley rats, of the same weight and age, housed singly were compared to their meal patterns after two weeks of housing in groups of three per cage. The feed intake and the feeding behaviour were recorded by computerised balances in combination with time lapse video recordings, during the group-housing period. Although when group-housed the rats made the same number of visits to the food cup as when housed singly, they ate more quickly, ate less per visit, and hence spent less time per day eating. The increase in eating rate was significant for the rats assigned to be the medium weight or lightest in their groups but not for the rats designated to be heaviest in their groups, indicating that the relative weight of the rats had an effect on their eating behaviour.

213
A rabbit model for liver fibrosis
by M. Kanter& Z. Yener

This experiment was carried out to investigate the role of cells participating in fibrosis induced by bile-duct ligation in rabbits. Histologically, bile stasis, degeneration and focal necrosis of hepatocytes, bile ductular proliferation, and an increase of the connective tissue were seen in periportal regions. Immunohistochemically, it was found that the majority of cells observed in the fibrosis regions were positive cells (spindle cells) for alpha-smooth muscle actin (ASMA). It is suggested that the spindle cells, probably transforming from Ito cells or myofibroblasts, play an important role in the pathogenesis of hepatic fibrosis.

223
Weighing used for the automatic registration of preferences when testing rats
by Thomas C. Krohn & Axel Kornerup Hansen

The preference test is one of the only behavioural test, which gives the animal an opportunity to make a free choice or indicate what it prefers and, therefore, it is widely used to evaluate whether an animal prefers one set-up to another. Providing what the experimental animal prefers (eg grids) will reduce stress, good for both experimental reliability and animal welfare.
In the present study the rat's preference for different cages was registered and recorded by digital weights. This study showed that this relatively simple set-up was applicable for registration of the preferences for different housing conditions, such as bedding or grid.

241
Meet a Research Group: András Simon, CMB, KI

243
Book Review

244
Meetings