2007 - Volume 34 - Issue 2

81-86
Numbers of Publications Related to Laboratory Animals
by Sihai Zhao, Enqi Liu,Yonglie Chu, Huadong Zheng, Shuji Kitajima & Masatoshi Morimoto

Laboratory animals are widely utilized in biomedical research, so a search of scientific publications can give us useful information on the use of animals. We retrieved the PubMed biomedicine database and searched for publications related to laboratory animals from 1966 to 2005. We found that rats and mice constitute the vast majority of species used in biomedical research; C57BL and BABL/c inbred mice, and Sprague Dawley and Wistar outbred rats are the most common strains. Recently, the numbers of publications relating to traditionally used animals such as rats, guinea pigs, dogs, cats, and sheep decreased slightly, whereas the numbers relating to mice, fish, Drosophila and Caenorhabditis elegans increased from 1995 to 2005, with annual mean growth rates of 4.5%, 8.22%, 1.95%, and 10.3%, respectively. Publications involving transgenic mice increased dramatically from the mid-1980s. This survey provides significant clues for predicting the future direction of biomedical research.

91-103
Characterisation of Spontaneous Behaviour in Göttingen Minipigs in the Home Pen
by Lene Vammen Søndergaard, Karin Hjelholt Jensen, Ralf Hemmingsen, Axel Kornerup Hansen & Nanna Marie Lind

Spontaneous behaviour in the home pen of group-housed minipigs was characterised with respect to social interaction, activity, locomotion, exploration and resting behaviour. Sixteen adult male and female Göttingen minipigs were allocated in three groups. Data were acquired at the age of seven and 16 months. Behaviour sampling was made by video recordings for two consecutive days per group. The median values for initiating and receiving social contact were one to four times per individual during 30 min of observation in the main “activity period” (found to be 4 – 4.30 pm with the feeding regime) at both ages; the variation between pigs was considerable. The animals spend a large amount of their active time (during this time) exploring (76 %). During the six-hours resting period, three bouts of activity were conspicuous in all three groups, and the highest level of activity was around midnight. The level of social interaction at seven and 16 months of age did not differ significantly, and the social hierarchy of the pigs in the three groups showed a high degree of consistency at seven and 16 months. However, correlation analysis did not indicate a statistically significant relationship between the level of social interaction of the individual pig at the young age and the older age. As relatively little is known about spontaneous behaviour of Göttingen minipigs this basal characterisation of normal behaviour may serve as normative data for future studies of Göttingen minipig behaviour.

109-113
Screening of Aflatoxin B1 in Laboratory Rat Feed
by Manuela Guerra, H. Marina Martins, Susana Ferreira, Mercedes Esquível & Fernando Bernardo

Many hazards can interfere with the safety of the feeding stuffs intended to provide nutrients to experimental animals. Chemical and biological contaminants of laboratory animal feed can be a problem for toxicological and immunological research. Aflatoxin B1 (AFB1) is a secondary toxic metabolite, produced by the ubiquitous fungal genera, Aspergillus. AFB1 is particularly dangerous for health, inducing cancer of the urinary tract or liver carcinoma. The aim of this preliminary screening was to evaluate the presence of AFB1 in 31 samples of laboratory rat feed using a method validated in-house, then separated by High Pressure Liquid Chromatography (HPLC) coupled to a fluorescence detector. The detection limit (limit of detection: LOD) and the quantification limit (LOQ) were 0.2 and 0.4 μg/kg respectively. Recoveries ranged from 58.0 to 74.5% for spiked samples. The immunoaffinity approach was significantly faster than methods employing conventional chromatography clean-up (Sep-Pak Classic Florisil and Sep-Pak ClassicC18 cartridges). Aflatoxins were not detected in any analysed sample.

119-126
Acute Phase Response of Albumin and Haptoglobin in Experimental Infection of the Olive Baboon, Papio Anubis, with Schistosoma Mansoni
by NWK Mungatana, RM Ngure & DS Yole

Following infection of baboons with Schistosoma mansoni cercariae, a rapid four-fold increase in mean serum haptoglobin concentrations was observed. These concentrations dropped to near pre-infection levels following curative treatment of the infected animals with praziquantel. On challenge of the animals with a second cercarial dose, haptoglobin concentrations demonstrated a more gradual increase that did not attain the heights of the initial infection. Albumin concentrations displayed an inversely disproportionate relationship to those of haptoglobin and decreases were much less pronounced. Whereas albumin was not a sensitive indicator of schistosomiasis mansoni, haptoglobin proved to be useful in detecting the acute infection and in determining prognosis of the disease in the olive baboon.

131-140
Hyperbaric Oxygen (HBO) Therapy after Partial Hepatectomy: An Experimental Study on Oxidative Stress in Rats
by Mehrdad Bohloli, Hafize Uzun, Erman Aytac, Akin Savas Toklu, Melih Paksoy, Haydar Durak & Turgut Ipek

In this study, we evaluated the effects of HBO therapy on oxidant and antioxidant status, and some histopathological parameters after partial hepatectomy in rats. There were three main experimental groups. The first group was sham (S) group (n=12), the second group was partial hepatectomized (PH) group (n=24) and the third group was after partial hepatectomy HBO-treated group (PH+HBO) (n=24). The HBO therapy was started the same day as partial hepatectomy for the PH+HBO group. Three subgroups (n=8) were assigned from the PH and HBO groups. The first, the second and the third subgroups were selected randomly, separated from the main groups and killed 2 days, 4 days and 7 days after partial hepatectomy respectively. Randomized selection from the main experimental groups and killing of the animals were done on the same day. Malondialdehyde (MDA), glutathione (GSH), nitric oxide (NO), mitotic index (MI), proliferating cell nuclear antigen (PCNA) levels and mean of cells with double nuclei were assessed. In the PH+HBO group, MDA and NO levels were decreased and MI, PCNA, GSH levels were increased significantly compared to the PH group. HBO therapy could activate antioxidant response and reduce oxidant activity after partial hepatectomy.