bluuebunny/crossref_metadata_2025 huggingface dataset:
Systems for collection of urine in the captive common marmoset, Callithrix jacchus
Authors: Lunn S. F.
Published: May 2007

Two systems are described for the collection of 24 h urine samples from the common marmoset ( Callithrix jacchus).

Using 84 adult animals, 1210 24-h samples were collected. Mean urinary excretion was 14·4±7·5 ml/24h ( n=1210, mean±SD). No differences were observed between sexes (for 52 females, 24 h volume=15·1±8·0 ml; for 32 males, 24 h volume=12·5±6·0 ml). No significant differences were observed between pregnant and non-pregnant females with respect to 24 h urine volume, and bilateral gonadectomy did not influence subsequent urinary excretion in either sex.

For 161 pairs of observations, the intake of drinking water (11·7±10·2 ml/24 h) and the volume of urine excreted (12·6±7·1 ml/24 h) showed a positive correlation r=0·406 d.f. 159, P<0·001: y=0·558 x+4·247).
Housing, breeding and selecting chickens of the Obese strain (OS) with spontaneous autoimmune thyroiditis
Authors: Dietrich H. M.
Published: May 2007

A management programme is described for a small colony of Obese strain (OS) chickens afflicted with spontaneous hereditary thyroiditis. Animals of this White Leghorn line are used as an animal model for Hashimoto's thyroiditis of man to study possible mechanisms of autoimmunity in general and organ-specific autoimmune diseases in particular. Due to the severe mononuclear cell infiltration of the thyroid glands, OS chickens show symptoms of hypothyroidism, including small body size, subcutaneous and abdominal fat deposits, long silky feathers, small combs and wattles, cold sensitivity, low fertility and poor hatchability. Successful breeding of this line, especially in a small population, can therefore be done only if rigid precautions are taken in aspects of animal care. The selection of breeding stock, the principal requirements for adequate housing and food, the artificial insemination procedure, and recommendations for collecting and incubating chicken eggs are reported in detail. Precautions necessary during the incubation of fertilized eggs, and fertility and hatchability are reported. During the hatching period several specific features must be considered. The important role of staff involved in a small chicken breeding unit is emphasized.
Tumours of the bone in C57BL/10J mice
Authors: Wadsworth P. F.
Published: May 2007

Tumours of the bone were found in 17 (12 females and 5 males) of 6768 (0·25%) C57BL/10J mice (3384 males and 3384 females) pooled from 14 oncogenic studies carried out from 1973 to 1987. Tumours of bone were found predominantly in female mice and were age related. The tumours were classified histologically as osteosarcoma (5 osteoblastic, 6 mixed type and 1 fibroblastic), chondroma (2), chondromyxoid fibroma (1), chondrosarcoma (1) and periosteal fibroma (1).
Objective clinical examination of poultry as illustrated by the comparison of chickens with different vitamin A status
Authors: Beynenl A. C. , Sijtsma S. R. , Kiepurski A. K. , West C. E. , Baumans V. , Van Herck H. , Stafleu F. R. , Van Tintelen G.
Published: May 2007

One day old pullets derived from marginally vitamin A deficient laying hens were fed diets containing either adequate or marginal amounts of vitamin A. At the age of 34 days, animals fed the diet low in vitamin A had group mean plasma concentrations of retinol which were one tenth the mean plasma concentrations of controls. When compared with their controls, the deficient animals displayed body weights which were on average 16% less. Of 20 pullets per dietary group one control animal and 9 deficient animals died by the age of 34 days. At the age of 29 days, control ( n=16) and deficient chickens ( n=11) were examined clinically by assigning scores to a number of parameters. Three assessors carried out the examination independently. The birds were presented for examination at random and their treatment groups were not disclosed to the assessors. Out of 26 parameters assessed quantitatively per individual animal, only three parameters discriminated between control and deficient chickens. Deficient animals grew poorly, had a hunched up posture and increased fluid content in faeces. Classical signs of chronic vitamin A deficiency in domestic fowl such as bone deformities, keratinization of the tongue and decreased transparency of the cornea were not observed.
Clinical examination of weanling rats with early zinc deficiency
Authors: Van Herck H. , Van Wouwe J. P. , Veldhuizen M. , Baumans V. , Stafleu F. R. , Beynen A. C.
Published: May 2007

In order to gain experience about the detection of adverse effects during a scientific procedure, we carried out a clinical examination of rats with zinc deficiency. In weanling rats fed a zinc-deficient diet (30 μmol zinc/kg) for 10 days, the mean tibial concentration of zinc was reduced by 53% and body weight gain by 73070 when compared with rats fed a diet containing an adequate amount of zinc (150 μmol zinc/kg). In a small open field on day 9 of the experiment, the deficient rats more frequently displayed the posture standing upright with elevated heels. On day 10 of the experiment a clinical examination was carried out at random and 'blind' by three independent assessors. Out of 20 variables scored quantitatively on each individual animal, only body size differed between normal and deficient rats. Other classical signs of zinc deficiency, such as alopecia, dermatitis and diarrhoea, were not detected. It is concluded that in this rat model of zinc deficiency, no evidence for extreme discomfort can be demonstrated.
Atypical epithelial thymomas in rats
Authors: Kaspareit-Rittinghausen J. , Deerberg F. , Sommer R.
Published: May 2007

The histopathological features of 2 atypical epithelial thymomas found in female Han: SPRD rats are described. The neoplasms were characterized by well-circumscribed epithelial nests and islands. One tumour showed local invasion in lymph vessels.
Difference in reproductivity and offspring growth between litter numbers in four strains of mice
Authors: Nagasawa H. , Koshimizu U.
Published: May 2007

As a means to improve mouse production, the differences among litter numbers in reproductivity, post-weaned growth and puberty of offspring were examined in 4 strains of mice, SHN/Mei, SLN/Mei, C3H/HeMei and GRS/AMei. Females were mated to be concurrently pregnant and lactating and reproductivity was recorded from the 1st to the 3rd litters. Some offspring of both sexes were weighed at 30, 40 and 50 days of age and vaginal opening was also checked in females.

Pre-weaned growth of offspring differed little between litter numbers in all strains except GRS/A. Meanwhile, post-weaned growth of offspring was higher in the 2nd and 3rd litters than in the 1st litter of SHN and SLN, associated with a decreased rate of still-born pups. In C3H/He, post-weaned growth of offspring was higher in the 1st and 2nd litters and rearing rate decreased for the 3rd litter. In GRS/A, the 1st litter showed the greatest pre- and post-weaning growth rate of offspring. All findings indicate that in SHN and SLN strains the later litters are better for offspring production, while in C3H/He and GRS/A strains it is the earlier litters. The results stress the value of having information on reproductive characteristics of mouse strains for efficient offspring production.
Consistency of laboratory animal food following incubation prior to autoclaving
Authors: Maerki U. , Rossbach W. , Leuenberger J.
Published: May 2007

In this study the conventional autoclaving technique was modified by incubating the food overnight prior to autoclaving. This treatment resulted in a markedly improved consistency of the food pellets, comparable with that of untreated food. The modified autoclaved food did not adhere to the walls of feeders or clog the transport passage. Furthermore, the losses in thermolabile vitamins resulting from this treatment were the same as those resulting from conventional autoclaving.
Anterior cervical microsurgical approach to the cranial base in the rabbit: technical note
Authors: Haworth Randal D. , Rosenberg Paul H. , Hoffman Lloyd A. , Latrenta Gregory
Published: May 2007

Current trends in research on craniofacial syndromes have led to enhanced interest in the cranial base as a contributory factor in the development of normal and abnormal midfacial structure. Indeed, attention has focused upon one particular growth plate in the posterior cranial base, the sphenooccipital synchondrosis, since it has been shown that alterations in this structure are associated with profound changes in craniofacial growth. In this report we describe a surgical approach to the cranial base of the rabbit that is safe, simple and reliable. It is applicable to neonatal as well as adult rabbits.
Lymphatic drainage of Listeria inonocytogenes and Indian ink inoculated in the peritoneal cavity of the mouse
Authors: Marco A. J. , Domingo M. , Ruberte J. , Carretero A. , Briones V. , Dominguez L.
Published: May 2007

The lymphatic drainage of the peritoneal cavity has been investigated by intraperitoneal inoculation of an intracellular bacterium ( Listeria monocytogenes) and an inert marker (Indian ink). The results reveal that both agents are transported, either after phagocytosis by intraperitoneal macro phages or in suspension in the lymph, towards the cranial sternal lymph nodes ( Lymphonodi sternales craniales) of the ventral thoracic Iymphocentrum ( Lymphocentrum thoracicum ventrale) and to the lymph nodes of the mediastinal lymphocentrum ( Lymphocentrum mediastinale), prior to systemic dissemination. This mechanism of peritoneal lymph drainage has relevance on experimental studies involving the inoculation of pathogens, and on the investigation of metastatic diffusion of neoplasms from the peritoneum.
The effects of buprenorphine, nalbuphine and butorphanol alone or following halothane anaesthesia on food and water consumption and locomotor movement in rats
Authors: Liles Jane H. , Flecknell P. A.
Published: May 2007

Locomotor activity and food and water consumption are potentially indices of post-operative pain in laboratory rodents, but it is important to establish whether these variables are directly affected by opioid analgesics or by halothane anaesthesia in normal rats. The effects of three opioids, buprenorphine, nalbuphine and butorphanol administered alone or following halothane anaesthesia, were studied in groups of normal non-operated adult Wistar rats.

All 3 analgesics affected food intake and activity levels, but had little or no effect on water intake. Buprenorphine caused a significant elevation of activity levels and a reduction in food intake at clinical doses (0·01 and 0·05 mg/kg s/c). Nalbuphine (0·5, 1 and 2 mg/kg s/c) caused a reduction in food intake but had a smaller stimulatory effect on locomotion. Butorphanol (0·4 mg/kg s/c) caused a reduction in food intake and elevation in activity. These results suggest that water consumption is likely to be a more reliable variable to use when assessing post-operative pain and the efficacy of analgesics in rats.
The assessment of depth of anaesthesia in animals and man
Authors: Whelan G. , Flecknell P. A.
Published: May 2007

The assessment of the depth of anaesthesia in man has received much attention in recent years, following a number of reports of people being aware during surgery. A range of different measures have been suggested for determining the adequacy of anaesthesia in man, but such a critical assessment is rarely applied to laboratory animals. This article describes the methods used to assess anaesthetic depth in both man and animals, and compares the relative states of knowledge about anaesthetic depth in animals and man.
A fast and simple technique for jugular catheterization in adult sows
Authors: Zanella A. J. , Mendl M. T.
Published: May 2007

Obtaining measures of an animal's physiological state with minimum disturbance to the animal is essential in animal welfare studies and it is also ethically desirable. A simple technique for implanting a temporary jugular catheter in adult sows is described. The technique involves implantation via an ear vein and can be performed in 5-7 min. Local but not general anaesthetic is required. The technique has no effect on basal levels of salivary cortisol 1-2 h later, suggesting that it has no long term stress consequences. Catheters continue to function perfectly well after 4 h.
The use of non-steroidal anti-inflammatory drugs for the relief of pain in laboratory rodents and rabbits
Authors: Liles Jane H. , Flecknell P. A.
Published: May 2007

The data concerning the use of non-steroidal anti-inflammatory drugs (NSAIDs) and evidence for their efficacy in laboratory rats and mice are reviewed. This information is then extrapolated to clinical situations and dose rates that take account of ulcerogenic side effects are recommended. NSAIDs have the potential to be a very useful group of analgesics and should always be considered when attempting to provide pain relief in laboratory animals.
The scope for improving the design of laboratory animal experiments
Authors: Festing Michael F. W.
Published: May 2007

The factors which need to be taken into account in designing a 'good' experiment are reviewed. Such an experiment should be unbiased, have high precision, a wide range of applicability, it should be simple, and there should be a means of quantifying uncertainty (Cox 1958). The relative precision due to the use of randomized block designs was found to range from 96% to 543% in 5 experiments involving 30 variables. However, a survey of 78 papers published in two toxicology journals showed that such designs were hardly used. Similarly, designs in which more than one factor was varied simultaneously ('factorial designs') were only used in 9% of studies, though interactions between variables such as dose and strain of animal may be common, so that single factor experiments could be misleading.

The consequences of increased within-group variability due to infection and genetic segregation were quantified using data published by Gärtner (1990). Both substantially reduced precision, but toxicologists continue to use non-isogenic laboratory animals, leading to experiments with a lower level of precision than is necessary.

It is concluded that there is scope for improving the design of animal experiments, which could lead to a reduction in animal use. People using animals should be required to take formal training courses which include sessions on experimental design in order to minimize animal use and to increase experimental efficiency.
The lipid composition of milk from mice fed high or low fat diets
Authors: Silverman Jerald , Stone Douglas W. , Powers Jean D.
Published: May 2007

Total fatty acids and the proportions of methyl esters of individual fatty acids were measured in mouse milk. Pregnant mice were fed either a high fat (OF) diet or a low fat (LF) diet from 14 days of gestation. After parturition, each dam was milked once a day for a period of 18 days. The mean total fatty acid concentration over the entire study period was 110 mg/g of milk (approximately 11·7% fat as triglyceride) for both dietary treatment groups. During days 2 to 6 postpartum, the mean total fatty acid concentration for dams fed OF diet was lower than for the LF group.

Although the concentration of total fatty acids of mouse milk was not affected by the level of dietary fat fed to the dam, several variations in the proportions of individual fatty acids were observed.
Microbiologically monitored fumigation of a newly built SPF laboratory rodent facility
Authors: Sebesteny Andor , Milite Gianpaolo , Martelossi Paola
Published: May 2007

The initial sanitization and sterilization of a newly built animal facility for the breeding and holding of specified pathogen free (SPF) rats and mice is described. The fumigation programme was started with methyl bromide treatment directed primarily against arthropods, followed by ammonia spray to kill coccidial oocysts and concluded by three formaldehyde treatments with fog and spray against bacteria and viruses. The practicalities and problems involved are described in detail and the rationale and purpose of the programme and its monitoring are discussed. The report is expected to contribute towards the establishment of a rational, efficient and standardized fumigation programme for SPF animal facilities, under increasing constraints of safety and environmental considerations concerning pollution with toxic and corrosive agents.
Chest roentgenographic techniques for demonstrating human lung tumour xenografts in nude rats
Authors: Zeligman Bernard E. , Howard Randy B. , Marcell Tere , Chu Henry , Rossi Raymond P. , Mulvin David , Johnston Michael R.
Published: May 2007

Roentgenographic techniques were investigated for imaging orthotopic lung tumours in anaesthetized nude rats endobronchially implanted with human lung cancer cells. A conventional radiographic unit with a dual-screen, double-emulsion film mammographic receptor produced images preferable to those from a mammographic unit because of superior resolution. Typical exposure factors were 300 mA, 29 kVp, and 17 ms at a focus-film distance of 76 cm with a 2·11 by 2·41 mm effective focal spot and inherent filtration of 1· 2 mm aluminium. Sensitivity for tumour detection was 0·93 for 59 animals with pathologically proved tumours and 0·96 for 54 animals with tumours larger than 4 mm or 50 mg. For 24 pathologically tumour-free animals, specificity was 1·00. For 55 animals radiographically judged to have tumours, positive predictive value was 1·00. For all 83 animals, accuracy was 0·95. This technique effectively demonstrates orthotopic human lung tumours in nude rats and should be useful for noninvasive monitoring of tumour presence, location, size, and changes in size.
Spontaneous inclusion body hepatitis in young tamarins: I. Morphological study
Authors: Stiglmair-Herb Maria Th. , Scheid Regine , Hänicheni T.
Published: May 2007

Over a period of 4 years approximately 60% of the new born and juvenile animals in a breeding colony of tamarins ( Saguinus fuscicollis) died a sudden death. Histological examination at necropsy revealed interstitial hepatitis in 22 of the 30 young animals of the present study. The hepatocytes contained intranuclear inclusion bodies in 12 of the 22 cases. Upon ultrastructural examination, tubulovesicular structures and amorphous material were found in the nuclei. The endoplasmic reticulum had proliferated and was closely associated with undulating curved membranes. These morphological alterations resemble those reported in chimpanzees experimentally infected with NANB hepatitis viruses.
Development of the KVL segregating inbred strain of the Syrian hamster (Mesocricetus auratus)
Authors: Salén J. C. W. , Worm K. , Hau J.
Published: May 2007

A new colony of a single segregating inbred strain of the Syrian hamster ( Mesocricetus auratus), designated KVL, has recently been developed at the Royal Veterinary and Agricultural University, Copenhagen, Denmark. The segregation occurs with respect to coat colour (pied gray/pied brown) as a result of inbreeding with forced heterozygosity. After 20 generations average litter size was 6·7 at birth and 5·57 at weaning. Mean generation interval was 89·4 days. An initially significant decrease in productivity (inbreeding depression) levelled out with further generations and has now stabilized. The colony is being maintained.
Allergy to laboratory mice and rats: a review of its prevention, management, and treatment
Authors: Hunskaar Steinar , Fosse Richard T.
Published: May 2007

Allergy to laboratory animals is reviewed from a management point of view. Personnel issues, medical therapy, legal aspects, animal house environments and work routines are discussed. Modern methods of medical treatment are presented but it is recommended that environmental control should be given priority over drugs. Several ventilation and building design systems are reviewed from an ALA viewpoint. New technology (including down-ventilated benches, ventilated cages) is reviewed and possible effectiveness analysed. These systems, though potentially of value, lack adequate testing under clinical conditions. We conclude that there are many clinically untested techniques that remain to be proven and whose efficacy has not been documented.
Handling and diet-induced atherosclerosis in rabbits
Authors: Jezierski T. , Mekking P. , Wiepkema P. R.
Published: May 2007

Atherosclerosis was induced in rabbits by feeding them a 2% cholesterol diet (CHOL) during a 5-week period. Twelve rabbits were fed with increasing amounts of CHOL food until the ad libitum level was reached, whereas in 24 other rabbits the food was limited to the amount eaten by the lowest consumer of the group to reduce individual variability in total amount of food consumed.

Twice a day, half of the rabbits were handled carefully, the other half had normal laboratory practice contact with their caretaker. Feed intake and amount of atherosclerosis were determined for all experimental animals, while for the handled animals behavioural parameters and changes were recorded daily and per animal. On average the handled and non-handled rabbits took the same amount of food per week, although there were large individual differences. The handled animals showed some behavioural adaptation to being handled. Handling had no influence on atherosclerosis size; this latter measure was only roughly determined by the amount of CHOL food eaten.
Anaesthetic effects of chloral hydrate, pentobarbitone and urethane in adult male rats
Authors: Field Karl J. , White William J. , Lang C. Max
Published: May 2007

Chloral hydrate, pentobarbitone and urethane were evaluated and compared for onset, duration and depth of anaesthesia, cardiovascular and respiratory effects, nociception and mortality in adult male rats. Chloral hydrate (300 and 400 mg/kg) severely depressed the cardiovascular and respiratory systems. Duration of anaesthesia was linearly related to dose, and anaesthetic depth and analgesia were excellent. Pentobarbital (40 mg/kg) produced a short period of light surgical anaesthesia. Moderate to severe respiratory and cardiovascular depression occurred. Duration of anaesthesia was not related to dose. Urethane (1·2 and 1·5 g/kg) caused moderate cardiovascular depression. In addition, mortality was high at the 1·5 g/kg dose. Duration of anaesthesia was greater than 24 h for most animals. Anaesthesia depth and analgesia were excellent.
An enzyme-linked immunosorbent assay (ELISA) for monitoring rodent colonies for Streptobacillus moniliformis antibodies
Authors: Boot R. , Bakker R. H. G. , Thuis H. , Veenema J. L. , De Hoog H.
Published: May 2007

An enzyme-linked immunosorbent assay (ELISA) to measure Streptobacillus moniliformis antibodies in mice and rats was developed. Twelve S. moniliformis strains originating from cases of rat-bite fever and Haverhill fever in man and from various rodent species, showed considerable serological relationship. The ELISA appeared specific since antibodies to S. moniliformis were absorbed by autologous and homologous antigen, but not by heterologous bacterial antigens. Acholeplasma laidlawii showed partial serological relationship with S. moniliformis.

The ELISA was validated using experimental infections in mice and rats. These studies and observations in naturally infected feral rats, confirmed that S. moniliformis is difficult to grow on primary isolation, and that the ELISA for S. moniliformis antibodies revealed more contaminated animals than culture.
Illustrated guide to surgical technique for vasectomy of the common marmoset
Authors: Morris Timothy H. , David Christopher L.
Published: May 2007

The surgical technique for vasectomy of the common marmoset ( Callithrix jacchus) is described and illustrated.
An enzyme-linked immunosorbent assay (ELISA) for monitoring guineapigs and rabbits for Bordetella bronchiseptica antibodies
Authors: Boot R. , Bakker R. H. G. , Thuis H. , Veenema J. L.
Published: May 2007

An enzyme-linked immunosorbent assay (ELISA) for monitoring antibodies specific to Bordetella bronchiseptica in guineapigs and rabbits was developed. In conventional and SPF colonies of guineapigs and rabbits, the ELISA was equally successful in detecting infected animals when compared to selective cultivation from the respiratory tract. The ELISA showed a sensitivity of 100% and a specificity of 90% in guineapigs. In rabbits the sensitivity and specificity of the ELISA were 97% and 91% respectively. In rabbit sera from infected colonies, ELISA activity showed a statistically significant correlation with titres obtained in the micro-agglutination test. Since serologically unrelated strains of the bacterium exist, the monitoring of animals for B. bronchiseptica infection by ELISA should be performed with various antigens.
Passage pressure across the uterotubal junction during the 4 phases of the oestrous cycle in the rat
Authors: Ortega-Moreno J. , Caballero-Gómez J. M.
Published: May 2007

The closure strength of the uterotubal junction (UTJ) was measured in 90 2.5 month old cycling female Wistar rats, assigned to 9 groups of 10 each. The passage pressure in both left and right UTJ were registered in pro-oestrus, oestrus, metoestrus and dioestrus phases. Five other groups were formed with rats which had been treated for 3 weeks with oestradiol (group E) or medroxiprogesterone acetate (group P), and with animals which had been ovariectomized 75 days prior to registering the pressure (ovariectomized group) or ovariectomized and treated with oestradiol (group Ov-E) or medroxiprogesterone acetate (group Ov-P).

The passage pressure of the right and left UTJ in each animal was similar in each of the groups. The pressures obtained in the oestrus phase or in the E and Ov-E groups were significantly smaller than those registered in dioestrus or in the P and Ov-P groups, and only slightly smaller than that obtained in the pro-oestrus and metoestrus phases. The results indicate that the swelling of the mucosa mediated by oestrogens is not the cause of the tubal locking in the rat.
Diarrhoea and increased intestinal permeability in laboratory beagles associated with proximal small intestinal bacterial overgrowth
Authors: Morris Timothy H. , Sorensen Susanne H. , Turkington John , Batt Roger M.
Published: May 2007

Repeated episodes of diarrhoea were seen in 4 laboratory beagles after experimental renal surgery and feeding a modified diet. Small intestinal bacterial overgrowth (SIBO) was suspected by exclusion of other causes and measurement of plasma folate. SIBO was confirmed by quantitative duodenal bacteriology. Beagles with SIBO can show no clinical signs, experimental stress and dietary change may have been reasons why these 4 beagles exhibited clinical signs with SIBO. Despite normal gut histology an increase in gut permeability was found using sugar absorption tests. This increased permeability had the potential to cause variations in drug absorption during experimental studies.
A simple method for repeated sampling of lumbar cerebrospinal fluid in goats
Authors: Peregrine Andrew S. , Mamman Mohammed
Published: May 2007

A technique has been developed for repeated sampling of cerebrospinal fluid from conscious goats by means of a catheter placed surgically in the subarachnoid space between the sixth and seventh lumbar vertebrae. Uncontaminated cerebrospinal fluid in excess of 1.0 ml could be obtained readily from the cannulated goats several times daily for up to 6 weeks. Cannulated goats did not appear stressed during, and in between, sampling periods.
Assessment of immunotoxicity of buprenorphine
Authors: Van Loveren H. , Gianotten N. , Hendriksen C. F. M. , Schuurman H. J. , Van Der Laan J. W.
Published: May 2007

In order to use buprenorphine as an analgesic in immunological experiments, we have studied the potential immunotoxicity of buprenorphine. Three-week-old male Wistar Riv: TOX rats were subcutaneously treated with buprenorphine by injection of 0.1, 0.4, or 1.6 mg/kg body weight per day over a period of 4 weeks. Concentrations used were within the range for analgesia in rats. A slight decrease of body weight gain was observed at the highest dose in one but not in a duplicate study. Decreased liver weights were observed in all dose groups. Histopathologically glycogen storage was decreased and fatty vacuolation was found to be increased starting from the lowest dose group. The relative but not absolute weight of the lungs was slightly increased at the lowest dose, this phenomenon was therefore not dose-dependent. Histopathologically, a dose-dependent increase in interstitial pneumonia in the lung was found. At the 2 higher dose levels the weight of the adrenal glands was increased. No haematological changes were found, nor were there effects on bone marrow.

In one of 2 studies indications of potential immunotoxicity noted were: an increased weight of the thymus, as well as an increased weight of popliteal and mesenteric lymph nodes. No effects on the weight of the spleen were found. Histologically, there were no changes in the lymphoid organs tested. Total immunoglobulin A concentrations in serum were significantly decreased in the highest dose group, whereas IgG concentrations were increased, albeit not statistically significantly. IgM and IgE concentrations showed no alterations.

Two types of immune function assays were carried out: determination of natural killer cell activity and of mitogen responsiveness of spleen cells. Whereas natural killer activity was unaffected, increased responses to concanavalin-A, phytohaemagglutinin, pokeweed mitogen as well as lipopolysaccharide were found, although never statistically significant.

The results indicate that buprenorphine may have a slight stimulatory influence on the immune system at dose levels that are used for analgesia. The effects on the immune system that were noted were modest. Moreover, they were observed in conjunction with other toxicological effects, and can therefore either be direct or indirect.
A simple technique to harvest two kidneys from one donor rat for transplantation
Authors: Yin M. , Booster M. H. , vd. Bogaard A. E. J. M. , Kootstra G.
Published: May 2007

Kidney transplantation in rats is a widely used and well established model in transplantation immunology and preservation research. With the conventional method, only one kidney is harvested from the donor rat. We developed a technique to harvest two kidneys separately from one donor, subsequently both kidneys were successfully implanted into two recipient rats. This technique which leads to a reduction of the number of experimental animals used is discussed in detail.
Efficiency of air filter sets for the prevention of airborne infections in laboratory animal houses
Authors: Mrozek Margund , Zillmann Uwe , Nicklas Werner , Kraft Volker , Meyer Barbara , Sickel Eckart , Lehr Bernd , Wetzel Anton
Published: May 2007

Air filter sets (classes EU6 and EU9, or EU6 and S) were tested for their efficiency in protecting laboratory animals against potential airborne infections. Flexible-film isolators were used as a smaller scale model. In the first experiment, lasting 7 months, it was tested whether minute virus of mice (MVM) was able to penetrate the airfilters between one isolator containing experimentally infected mice and another with MVM negative mice. In the second experiment we tested whether microorganisms in the incoming air were able to penetrate air filter sets. To assess this gnotobiotic mice in an isolator were monitored for 9 months for changes of their microbial flora. In both experiments a combination of EU6 and EU9 air filters proved to be sufficient to maintain the microbiological status of the animals. The same combination of medium efficiency filters (EU6 and EU9) is used on the air supply to 4 SPF-barrier units in which infections with MVM occurred repeatedly soon after the initial stocking. After a thorough disinfection no reinfection has been detected to date. This demonstrates that the relatively low efficiency of the air filters was not the cause of the repeated infection. The procedure for disinfection is described.
Medetomidine, an α2-agonist, alleviates post-thoracotomy pain in dogs
Authors: Vainio Outi , Ojala Merja
Published: May 2007

Twelve laboratory beagles underwent a routine left thoracotomy to insert permanent instrumentation. Every second dog was given 10 μg/kg of medetomidine, an α2-agonist sedative. The rest of the animals were treated with 20 μg/kg of buprenorphine, an opioid agonist-antagonist, which is regularly used to treat postoperative pain in laboratory animals. The drugs were given at the end of operation (0) and 4, 8, 20, and 24 h postoperatively. Blood samples for catecholamines (adrenaline and noradrenaline) and blood gases (pCO2 and pO2) and pH were drawn immediately before any drug administration, and 30 min later. At the same time points, the pain level was subjectively evaluated using a pain score, and heart rate and rectal temperature were measured.

Adrenaline and noradrenaline concentrations were lower in the medetomidine group than in the buprenorphine group. Accordingly, it was concluded that medetomidine had better analgesic effect than buprenorphine in the treated animals. This result was supported by subjective evaluation of the severity of pain, even though subjective evaluation is not considered very reliable in the present kind of open studies.

pO2 was lower in the buprenorphine group than in the medetomidine group after the first injection of the analgesics. pCO2 and pH were similar in both of the groups. Medetomidine decreased heart rate after every injection, this fall and subsequent rise might be avoided by a lower dose regime. Buprenorphine did not effect heart rate. Rectal temperature did not differ in either group. It was concluded that medetomidine, and other α2-agonists, possess some potential in postoperative pain alleviation.
A technique for catheterization of the urinary bladder in the ferret
Authors: Marini R. P. , Esteves M. I. , Fox J. G.
Published: May 2007

The technique of catheterization of the urinary bladder, an important clinical skill for the diagnosis of urinary tract disorders, has not been described for the ferret. The bladder was catheterized in 23 ferrets (10 intact females; 11 spayed females; and 2 intact males) using a 3½ French, red rubber urethral catheter fitted with a steel wire stylet. Ferrets were anaesthetized with isoflurane or ketamine (30mg/kg IM) and xylazine (3mg/kg IM). Females were positioned in ventral recumbency with the rear quarters elevated by a rolled surgical towel. The urethra was catheterized by direct visualization of the external urethral orifice using a vaginal speculum. The orifice was approximately 1 cm cranial to the clitoral fossa on the ventral floor of the vestibule. Blind passage was used in several spayed females. In males, the distal end of the penis was exteriorized from the prepuce and the external urethral orifice cannulated without stylet. No difficulty was encountered in advancing the catheter past the os penis. This catheterization technique allows urinary tract access for urine collection, pneumocystography, contrast cystography, double contrast cystography, and urine output determination in pharmacologic studies or in critical care of debilitated animals.
A new method for measuring the blood volume of the rat using 113mlndium as a tracer
Authors: Argent N. B. , Liles Jane , Rodham D. , Clayton C. B. , Wilkinson R. , Baylis P. H.
Published: May 2007

A new method is described for the estimation of blood volume in the rat using 113mIndium chloride. No in vitro labelling step is necessary as the isotope binds specifically to transferrin in vivo. Under anaesthesia, an external jugular vein was cannulated for blood sampling and indium chloride injected directly into a lateral tail vein. Three blood samples of 0.2 ml were taken at short intervals and radioactivity measured under standard conditions. Blood volume was found to be 7.46±0.14 (mean ± SEM) ml/100 g body weight. Repeating the study of 5 animals gave similar values for blood volume on the 2 occasions (7.23±0.26 and 6.95±0.23ml/100g, P>0.05). The new technique was compared with established methods using SlCr labelled red blood cells and 125Iodinated albumin. In each animal, the l13mIndium technique produced values approximately 10% higher than those obtained using the sum of plasma and red cell mass, in keeping with the known difference between whole body and large vein haematocrit (Indium, 7.20±0.19 and Iodine with Chromium, 6.40± 0.34 ml/100 g). Data on blood volume determined using 125Iodine as the tracer on these same animals were identical (Indium, 7.20±0.19 and iodine, 7.16±0.34ml/100g). The method is simple to perform and appears to be at least as accurate and reproducible as established methods for measuring blood volume.
Historical histopathological control data for laboratory rodents: valuable treasure or worthless trash?
Authors: Roe F. J. C.
Published: May 2007

The reasons for variation in longevity and disease incidence in untreated control animals in chronic toxicity and carcinogenicity tests in laboratory rodents are reviewed and discussed. Genetic drift, dietary composition, caloric intake, age of animals at the termination of studies, the skill, experience and diligence of the pathologist, the diagnostic criteria used and the appropriateness of statistical procedures are considered to be the most important sources of variation. It is suggested that more attention needs to be paid to the sources of nutrients in animal diets and that 'closed formula' diets should be eschewed. The reliability of historical data depends critically on the extent to which 'like' can be compared with 'like'. The most important variables in relation to histopathological data are considered in this context.
Effects of Intralipid infusion on rat serum lipoproteins
Authors: Wasan Kishor M. , Grossie V. Bruce , Lopez-Berestein Gabriel
Published: May 2007

The purpose of this investigation was to study the effects of continuous Intralipid® infusions on serum HDL and LDL levels in the rat. Male Fischer 344 rats were infused continuously via central venous catheter with 10% Intralipid® for 96 h and 5, or 2.5% Intralipid for 14 days. Blood samples were collected during the infusion period for total serum cholesterol, HDL-, and LDL-cholesterol measurements. Food intake was monitored during the studies. Total cholesterol, HDL-cholesterol and LDL-cholesterol levels were significantly elevated following 96 h of infusion with 10% Intralipid with food intake significantly decreased compared to a control group. In a second experiment, animals received a continuous infusion of either 5% Intralipid, 2.5% Intralipid or 0.45% saline for 14 days. Total cholesterol, HDL-cholesterol and LDL-cholesterol were significantly elevated following 14 days of infusion with 5% Intralipid group compared to controls but food intake remained constant for 12 days with no evident toxicity.
Rapid genotyping of low density lipoprotein receptor knockout mice using a polymerase chain reaction technique
Authors: Gaw Allan , Mancini Francesco P. , Ishibashi Shun
Published: May 2007

A new method for the rapid genotyping of low density lipoprotein receptor knockout mice is described. This method using a polymerase chain reaction (PCR) technique may be performed on small tissue biopsies, and represents a significant advantage in time over conventional genotyping by Southern blot analyses.
Non-phenotypic detection of osteopetrotic (op/op) mutation by using PCR-SSCP analysis
Authors: Kaneko H. , Iizuka K. , Morohashi T. , Kokai Y. , Fujimoto J.
Published: May 2007

Mice homozygous for recessive mutation osteopetrosis ( op/op) on chromosome 3 provide a unique model to study the mechanism of haematopoiesis in conjunction with bone formation. Based on the DNA sequence data recently reported, we established a PCR-SSCP (polymerase chain reaction-single strand conformation polymorphism) assay which identifies an amplified fragment having an insertional point mutation present in macrophage colony-stimulating factor (M-CSF) gene of op/op mice. With this assay, three genotypes, op/op, + /op, and +/+ can be distinguished. Although heterozygous (+/ op) and normal (+/+) mice could not be discriminated phenotypically, we could generate op/op mutant mice starting from a single heterozygous (+/ op) mouse using only the PCR-SSCP aided screening method. This assay will permit introduction of the op mutant into any strain to generate a new animal model to study the cytokine network and haematopoiesis.
An investigation into the effects of solid or grid cage flooring on the welfare of laboratory rats
Authors: Manser C. E. , Morris T. H. , Broom D. M.
Published: May 2007

The welfare of laboratory rats housed on either solid or grid floors was investigated in several ways. No differences were found in body weight gain, food consumption or water consumption amongst rats housed in either condition. When handling was standardized between the 2 groups, there was no correlation between flooring and docility. Preference testing revealed that rats chose to dwell on solid floors rather than grids, regardless of previous housing experience. This preference for solid floors was particularly marked (88%) when the animals were resting and much less marked during activity (55.4%). Since the rats were observed to spend 70 to 75% of their time resting, it was concluded that their welfare was likely to be improved by housing them on solid floors.
Spontaneous rhabdomyosarcomas in aged Mastomys (Praomys coucha)
Authors: Madarame Hiroo , Kashimoto Yoshinori , Kawamoto Tsuyoshi , Toyonaga Shinya , Hasegawa Yoshihisa
Published: May 2007

Two spontaneous tumours in the hind leg of 2 aged Mastomys were diagnosed as poorly differentiated rhabdomyosarcomas. In both cases, the neoplastic cells had no evidence of cross-striation, but had a positive reaction for muscle-specific proteins. This is the second report of rhabdomyosarcomas in Mastomys, and the first described in detail.
Choice of vehicle for three-month continuous intravenous toxicology studies in the rat: 0.9% saline versus 5% glucose
Authors: Salauze D. , Cave D.
Published: May 2007

A study to assess the toxic potential of a candidate-drug administered to unrestrained rats as 1-h infusions thrice daily for 3 months, using 5% glucose as vehicle, had to be aborted on day 34 because of poor physical status and mortalities in all groups, including controls receiving the vehicle alone. Investigation demonstrated an opportunistic infection, probably secondary to the glucose present in the intravenous formulation. A second study using 0.9% saline solution as a vehicle, was successfully completed.
Spleen pigmentation in young C57BL mice is caused by accumulation of melanin
Authors: van der Heijden A. , van Dijk J. E. , Lemmens A. G. , Beynen A. C.
Published: May 2007

It has been previously reported that in 2 C57BL mouse sublines a dark pigmentation of the cranial part of the spleen occurs in up to 30% of the animals within the populations. It was not clear whether this discoloration is caused by melanosis, lipofuscinosis or haemosiderosis. With the use of light and electron microscopy of stained spleen sections, we identified the pigment in 14 out of 60 C57BL mice aged 8-10 wks. In the mice with pigmented spleens there was accumulation of melanin, predominantly in melanophores. Literature data indicate that apart from melanin, lipofuscin and haemosiderin can be observed in splenic macrophages provided that the mice are older than those studied by us. We conclude that melanin is the principal pigment causing spleen discoloration in young C57BL mice. Splenic melanosis displays inter-individual variation, but its relevance from a pathophysiological point of view remains obscure.
Arterial lesions in hypercholesterolaemic Yoshida rats: morphological evaluation
Authors: Kolpakov Valeri , Di Sciullo Anna , Polischuk Roman , Nasuti Mimmo , Di Nardo Patrizia , Mironov Alexander , Poggi Andreina
Published: May 2007

The aortic wall structure of genetically determined hypercholesterolaemic (Yoshida) and control (Brown-Norway) rats was investigated by transmission and scanning electron and light microscopy. Leucocyte adherence mostly at branch sites and irregular protrusive structures were observed on the endothelial surface of the thoracic aorta of Yoshida, but not of Brown-Norway rats. The subendothelial space of the aortic wall of Yoshida rats was characterized by intimal cushions consisting of smooth muscle cells of 'synthetic phenotype' associated with adhering leucocytes and lipid droplets. Lipid infiltration of the cytoplasm of medial smooth muscle cells was observed on the inner part of the aortic arch and on the lateral parts of the large branches of Yoshida rats. This model of spontaneously hyperlipidaemic Yoshida rats is an appropriate 'moderate' injury system, which may be useful for studies of multiple risk factors for atherogenesis.
Cell counts in peripheral blood and bone marrow of male C.B-17 scid/scid mice
Authors: Matsumoto Kiyoshi , Inukai Shin-ichi , Isaka Tetsuo , Aruga Norisato , Nakamura Shunji , Nagasawa Tatsuya , Naito Jun
Published: May 2007

Blood cell and bone marrow cell counts were carried out for male C.B-l7 scid/scid (SCID) mice aged 3, 6, 9, 18 and 26 weeks and the values were compared with those in C.B-17+/+(C.B-17) mice. In the peripheral blood, SCID mice had markedly low numbers of leucocytes and lymphocytes throughout the study. In the bone marrow, SCID mice had relatively low levels of erythroblasts at an early age, low levels of lymphocytes and plasma cells were absent.
Stress measurements in mice after transportation
Authors: Tuli J. S. , Smith J. A. , Morton D. B.
Published: May 2007

Experiments were performed using physiological measures and behavioural parameters to find the acclimatization period in mice to common scientific procedures. Corticosterone levels were significantly elevated in mice killed immediately after being moved to an experimental room ( P<0.05) but levels returned to the normal in less than 1 day, despite mice being exposed to additional stressors such as novel environment, new cages, new bedding material, separation from their cage mates, regrouping, isolation in individually housed mice and a new handler. Behaviours such as rearing, climbing, grooming, feeding and sexual, changed significantly immediately after transportation of mice but most of these behaviours stabilized relatively quickly. In spite of the corticosterone levels, our behavioural observations suggest that even 4 days were not enough to allow the mice to acclimatize fully.
Encephalomyocarditis (EMC) virus infection in the common vole, Microtus arvalis
Authors: Doi K. , Ikegami H. , Ishii K. , Doi C. , Yamanouchi Y. , Sugano S.
Published: May 2007

Encephalomyocarditis (EMC) virus infection in the common vole was examined for the first time. Sixteen 8-week-old males inoculated intraperitoneally with 105 plaque-forming units (pfu)/animal of the D variant of EMC virus were killed 3 and 7 days after inoculation (3 and 7 DAI). Viral replication was detected in the brain (105 pfu/g), heart (104 pfu/g) and pancreas (107 pfu/g) of all 8 animals at 3DAI. It was found in the pancreas (103 pfu/g) of all 8 animals and in the brain (104 pfu/g) of 2 of 8 animals at 7 DAI. Histopathological changes were observed in the brain (mild mononuclear cell infiltration around capillaries and sporadic pyknosis of neurons), heart (minimal myocardial necrosis) and pancreas (prominent acinar cell necrosis with inflammatory exudation) at 3DAI. At 7 DAI, replacement of necrotic tissues by mesenchymal cells and regeneration of acinar cells were conspicuous in the pancreas. Throughout the experimental period, no evidence for diabetogenic effect was found.