bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment of genetic variability in populations of Nacobbus aberrans (Thorne, 1935) Thorne & Allen, 1944 (Nematoda: Pratylenchidae) from Argentina
Authors: Lax Paola , Rondan Dueñas Juan , Gardenal Cristina N. , Doucet Marcelo E.
Published: May 2007

Nacobbus aberrans produces severe damage to agriculture and is considered to
be of quarantine importance. The levels of polymorphism and genetic
differentiation among Argentine populations of this species from different
hosts and origin were studied using Inter-Simple Sequence Repeat (ISSR) as
molecular markers. Second-stage juveniles from nine populations associated
with three different hosts (tomato, quinoa and potato) were analysed
individually. Three primers were selected because they produced clear and
100% reproducible patterns; 37 fragments were considered for the analysis.
The technique employed revealed high levels of polymorphisms, the highest
proportion of genetic diversity being found within populations (95%).
Populations showed a tendency to group together according to their original
host, based on their pairwise FST. Low levels of genetic differentiation
among populations were observed, suggesting an extensive gene flow among
them. Passive dispersal of nematodes by natural means and anthropogenic
activities would probably be, at least partially, responsible for the
results observed. This work is the first study of genetic structure of N.
aberrans populations at a macrogeographical level using ISSR markers.
Description of Aulolaimus multipapillatus sp. n. and A. nannocephalus Andrássy, 1972 with notes on taxonomy and phylogeny of the genus (Nematoda: Aulolaimidae)
Authors: Holovachov Oleksandr , Boström Sven , Susulovsky Andrij
Published: May 2007

One new and one known species of Aulolaimus are described, viz. A.
multipapillatus sp. n. from Israel and A. nannocephalus from Ukraine.
Aulolaimus multipapillatus sp. n. is particularly characterised by a cuticle
bearing ca 60 distinct longitudinal ridges, cuticle with distinct
ornamentation on ventral body side anterior and posterior to vulva, 6-11
midventral sensilla anterior to cloaca, and spicules ca 25 μm long.
Aulolaimus nannocephalus is redescribed on the base of both light and
scanning electron microscopic observations on two populations from Ukraine.
An emended diagnosis and a revised classification of the genus are proposed.
The morphological variability and systematic position of Aulolaimus are
discussed and a key to the species of the genus is provided.
Bursaphelenchus uncispicularis n. sp. (Nematoda: Parasitaphelenchidae) from Pinus yunnanensis in China
Authors: Zhuo Kan , Li Xundong , Li Danlei , Yu Shengfu , Liao Jinling
Published: May 2007

Bursaphelenchus uncispicularis n. sp. is described and figured. The nematode
was found in wilted pine Pinus yunnanensis Franchet from a single locality
in Longling county, Yunnan Province, China. The new species is characterised
by a relatively small stylet (11-15 μm long) with weakly developed basal
swellings and lateral fields bearing four incisures. The male has relatively
small, arcuate spicules with a distinct, dorsally bent, hook-like condylus,
thorn-like rostrum, distinct cucullus and an ovoid terminal 'bursa' with
minutely tripartite terminus. The female has a minute vulval flap and a
conical tail with a relatively robust and blunt projection ca 1.2-4.5 μm
long. Both sexes are of moderate body length ranging from 676-1088 μ m in
the female and 552-1083 μm in the male with a slender body (a = 37-54 in the
female and 36-54 in the male) and a relatively short tail (c = 26-39 in the
female and 31-45 in the male). Bursaphelenchus uncispicularis n. sp. most
closely resembles B. borealis, B. leoni and B. silvestris. However, the new
species is easily distinguished from these three species by a number of
characters including spicule size and shape, female tail shape and length,
and postvulval uterine sac length.
Effects of various stress factors on heat tolerance by Heterorhabditis bacteriophora and Steinernema carpocapsae
Authors: Bilgrami Anwar , Gaugler Randy
Published: May 2007

Centrifugation, desiccation, agitation, and handling of entomopathogenic nematodes in the laboratory during isolation, culture, storage, formulation and experimentation, influences nematode ability to tolerate adverse environmental conditions. Stress imposed by centrifugation (5-60 min), desiccation (3-9 days), agitation (3-24 h), and handling (2-10 times) reduced stress and heat tolerance in Heterorhabditis bacteriophora and Steinernema carpocapsae. Short durations of stresses (e.g., 5 min of centrifugation, 3-5 days of desiccation, 3 h of agitation and 2-4 times of handling) did not affect nematodes, whereas prolonged durations (e. g., 10-60 min of centrifugation, 7-9 days of desiccation, 6-24 h of agitation and 6-10 times of handling) significantly decreased heat tolerance. Steinernema carpocapsae tolerated stress comparatively better than H. bacteriophora by showing a significantly greater degree of heat tolerance. This study provides a basis to investigate further the effects of physical and chemical stresses in order to minimise handling of laboratory nematodes and reduce disruptions of their normal function and behaviour.
An immunogold cell labelling method for rat T lymphocytes
Authors: Evans G. O. , Flynn R. M. , Lupton J. D.
Published: May 2007

A method using monoclonal antibodies in conjunction with an immunogold procedure was adapted for labelling T lymphocytes in blood samples obtained from male Wistar rats. The monoclonal antibodies W3/25, MRC/OX8 and W3/13 were used. Changes in the percentages of positively labelled cells were observed in rats dosed with the immunosuppressant cyclosporin.
Coprophagy in marmosets due to insufficient protein (amino acid) intake
Authors: Flurer C. I. , Zucker H.
Published: May 2007

In the course of experiments to study the minimal protein requirement of common marmosets by nitrogen balance methods, coprophagy was observed. It occurred in most animals fed diets either with a protein content below 6% or lacking histidine/arginine. The protein level of 6% had previously been evaluated as being the minimal protein requirement for maintenance of marmosets.
Differences in the gastrointestinal micro biota of specific pathogen free mice: an often unknown variable in biomedical research
Authors: O'Rourke J. , Lee A. , McNeill J.
Published: May 2007

Large differences were found in the numbers of facultatively anaerobic Gram-negative bacteria in the gastrointestinal tract of mice from 3 major specific pathogen free (SPF) units in Australia. The species isolated also differed between mouse colonies.

In one unit the presence of Enterobacter cloacae was found to dramatically influence the survival of mice following total body irradiation. This finding conforms with previous studies which have shown the influence of variation in gastrointestinal micro biota on the immune system and on susceptibility to infection.

Given that the presence or absence of Enterobacteriaceae in the intestines of mice under investigation may influence experimental results, researchers using SPF rodents are encouraged to determine the baseline loading of these bacteria in their animals. Where results of immunological or irradiation studies from different colonies are likely to be compared, the enterobacterial status of the colony being used should be reported.
Plasma exchange technique in the unheparinized, unanaesthetized rat
Authors: Reding R. , White D. J. G. , Davies H. ff. S. , Calne R. Y.
Published: May 2007

An inexpensive and convenient plasma exchange technique has been developed in the rat, which avoids heparin and membrane plasmapheresis technology. The use of a reliable venous vascular access on unanaesthetized, briefly restrained animals is described.
Serodiagnosis of Streptococcus pneumoniae infection in guineapigs by an enzyme-linked immunosorbent assay
Authors: Matsubara J. , Kamiyama T. , Miyoshi T. , Ueda H. , Saito M. , Nakagawa M.
Published: May 2007

Guineapig antibodies to Streptococcus pneumoniae (SPN) serotype 19F were detected by an enzyme-linked immunosorbent assay using a simple procedure. In experimentally infected hosts, antibody was detectable as early as 2 to 3 weeks after infection, and high titres were maintained for a long period. Antibodies higher than 1 : 64 were regarded as specific. In a field study, high antibody titres were shown in SPN enzootic colonies in contrast to negative or low antibody titres in a majority of the animals from non-enzootic and SPF colonies.
Spontaneous glomerular immunoglobulin deposition in young Sprague-Dawley rats
Authors: Goode N. P. , Davison A. M. , Gowland G. , Shires M.
Published: May 2007

The frequency, age-onset and distribution of spontaneously deposited immunoglobulins (lgs) in glomeruli of Sprague-Dawley rats has been investigated. Groups of rats ( n=10) were examined at 4-7 day intervals from birth (presuckling) until 30 days of age. Findings were compared with circulating immunoglobulin concentrations in each age group. Immunoglobulins were undetectable in immature kidneys of newborn rats. However, as early as 5 days, scanty IgA and IgM deposits were observed predominantly in mesangial areas of mature glomeruli, corresponding to low circulating concentrations of these immunoglobulins. By contrast, glomerular IgG deposits were not observed until 21 days, despite relatively high concentrations of circulating maternal IgG from birth. Mesangial deposition of immunoglobulins increased with age. Absence of complement C3c or electron dense deposits associated with this mesangial localization suggests that immunoglobulins were not deposited as immune complexes.

Accumulation of non-phlogogenic immunoglobulins in the mesangium of normal rats supports the concept that the mesangium is constantly perfused by circulating macro-molecules and filtration residues. The results indicate problems of interpretation of the significance of endogenous immunoglobulin deposition in models of experimental glomerulonephritis, even in studies involving weanling rats.
Ketamine-xylazine anaesthesia in the Djungarian hamster (Phodopus sungorus)
Authors: Curl J. L.
Published: May 2007

The combination of ketamine-xylazine was assessed as a surgical anaesthetic in Djungarian hamsters acclimatized to both long (16h light: 8 h dark) and short (8 h light: 16 h dark) photoperiods. It was concluded that 50 mg/kg of ketamine with 10 mg/kg of xylazine or 100 mg/kg of ketamine with 5-10 mg/kg of xylazine when given together by intraperitoneal injection was a satisfactory general anaesthetic. Two hundred mg/kg of ketamine with 10 mg/kg xylazine caused death in 13 of 24 animals. There were no clinically significant effects on depth of anaesthesia due to photoperiod.
An epizootic infection of Citrobacter freundii in a guineapig colony: short communication
Authors: Ocholi R. A. , Chima J. C. , Uche E. M. I. , Oyetunde I. L.
Published: May 2007

An epizootic infection of Citrobacter freundii in a guineapig colony is reported. From 1300 guineapigs maintained in a colony, a total of 115 guineapigs died. Lesions found postmortem were suggestive of acute pneumonia and enteritis. Citrobacter freundii was consistently isolated from necropsy specimens of lung, liver, spleen and intestines of the animals. The source of infection was not ascertained.
The use of metronidazole, tinidazole and dimetridazole in eliminating trichomonads from laboratory mice
Authors: Roach P. D. , Wallis P. M. , Olson M. E.
Published: May 2007

Metronidazole, tinidazole and dimetridazole were administered in the drinking water for 5 days to mice experimentally infected with Tritrichomonas muris and Tetratrichomonas microta. Mice were successfully infected with T. muris and T. microta recovered from infected gerbils. The trichomonas infection was successfully eliminated in mice given a 1% sucrose solution containing 2·5 mg/ml metronidazole or tinidazole. Mice receiving 1·0 mg/ml metronidazole, 1·0 mg/ml tinidazole and 1·2, 5·0 and 10·0 mg/ml dimetridazole failed to eliminate the trichomonas organism. A reduction in water intake was only noted with mice receiving 10 mg/ml dimetridazole. In mice receiving only 1% sucrose the infection was not eliminated.
Serological evidence for Encephalitozoon cuniculi infection (nosemiasis) in gnotobiotic guineapigs
Authors: Boot R. , Van Knapen F. , Kruijt B. C. , Walvoort H. C.
Published: May 2007

Encephalitozoon cuniculi infection (nosemiasis) was serologically diagnosed in hysterectomy-derived gnotobiotically reared guineapigs. The probability of vertical transplacental transmission is discussed.
Craniopharyngioma in the Mongolian gerbil (Meriones unguiculatus): case report
Authors: Guzmãn-Silva M. A. , Rossi M. I. D. , Guimaraes J. S. P.
Published: May 2007

A case of spontaneously occurring infiltrative craniopharyngioma in a laboratory-reared gerbil is reported. The histopathological and ultra-structural features are described.
Improved technique for the mixed lymphocyte response in the Chacma baboon
Authors: Smit J. A. , Stark J. H. , Myburgh J. A.
Published: May 2007

Lymphocyte responsiveness in cells collected from baboons ( Papio ursinus orientalis) has consistently been 1/10 of that obtained using human cells. Animals that vigorously rejected organ allografts demonstrated that this lack of responsiveness was not due to genetic identity. This paper defines the kinetics of the baboon mixed lymphocyte response (MLR) and suggests several modifications to improve the sensitivity of the technique. Optimal response was obtained using nylon wool purified T-cell responders, 20% fresh autologous plasma to supplement culture medium, an incubation period of 6 days and exposure to 3H-thymidine (2 Ci/mmol) for 24 h prior to harvesting. These modifications enhanced the MLR response from a stimulation index±standard error of 2·5±0·3 ( n=79) to 25·2±5·4 ( n=38).
Osmotic fragility of erythrocytes of two breeds of domestic fowl in the warm humid tropics
Authors: Oyewale J. O. , Durotoye L. A.
Published: May 2007

Erythrocyte (RBC) count, packed cell volume (PCV) and haemoglobin (Hb) values were found to be higher in Nigerian domestic fowls than those in Hubbard fowls. PCV and Hb values were higher in males than in females in both breeds. Erythrocytes of the Nigerian fowl were observed to be more susceptible to osmotic haemolysis than were erythrocytes of the Hubbard fowl. Erythrocytes of male fowls were osmotically more fragile than were those of female fowls in both breeds.
The use of repeated treatment with Ivomec and Neguvon spray in the control of murine fur mites and oxyurid worms
Authors: Baumans V. , Havenaar R. , Van Herck H.
Published: May 2007

In a previous study, a single external treatment with Ivomec appeared to be more effective than Neguvon treatment. In this study the anti-endoparasitic qualities of external application of Ivomec were investigated, together with the effectiveness of a combined Neguvon and Ivomec treatment. After 3 treatments, all mice were mite- and worm-free: they remained free of ectoparasites until 18 weeks after the last treatment; eggs of endoparasites reappeared 9 weeks after the last treatment.
An analgesiometry system for use in rabbits with some preliminary data on the effects of buprenorphine and lofentanil
Authors: Wootton R. , Crosst G. , Wood S. , Westt C. D.
Published: May 2007

A low cost infrared skin heating system has been designed to measure the efficacy of analgesics in rabbits. Following construction of a prototype, it was used to assess the effect of buprenorphine given subcutaneously and per rectum. Buprenorphine administered subcutaneously has a rapid onset of action, but its duration (8-10 h) appears slightly shorter than has been suggested previously; rectal administration appears to prolong its effect. Preliminary data show that lofentanil has a longer duration of action than buprenorphine and it may prove, therefore, to be a valuable long-acting analgesic in the rabbit.
Leucocyte alkaline phosphatase in the Mongolian gerbil and other species: a comparative view
Authors: Tamburlin J. H. , Glomski C. A.
Published: May 2007

Cytochemical analyses performed on peripheral blood smears of the Mongolian gerbil reveal the presence of variable amounts of leucocyte alkaline phosphatase (LAP) activity in the neutrophil of this species. Levels of activity in individual cells ranged from 1 to 4+. Cells completely devoid of activity were rarely encountered. Immature neutrophils residing in the bone marrow also displayed moderate amounts of enzymatic activity. The results of a semiquantitative assessment of overall LAP activity in this rodent, expressed as a mean LAP score, were compared with similar analyses carried out on a diverse sample of vertebrates. Intermediate levels of activity were recorded for the gerbil ( x̄=241). This score was comparable to that obtained for the rat x̄=199) and significantly higher than that seen in man x̄=79). A wide range of LAP scores were noted for closely related species, as well as phylogenetically distant species.
Genetic monitoring of rat strains using monoclonal antibodies specific for polymorphic class I and class II MHC antigens
Authors: Fernandez J. L. , Weeks M.
Published: May 2007

An enzyme-linked immunoassay using monoclonal antibodies, specific for polymorphic class I and class II MHC antigens distributed among inbred, congenic and hybrid strains of rats, was developed, in order to provide an easy means of identifying different strains of rats by typing their blood cells.
An evaluation of three anaesthetic regimes in the gray short-tailed opossum (Monodelphis domestica)
Authors: Keller L. S. F. , Drozdowicz C. K. , Rice L. , Bowman T. A. , Lang C. M.
Published: May 2007

The effect of several anaesthetic agents on the gray short-tailed opossum ( Monodelphis domestica) was investigated. Pentobarbitone sodium at a dose of 50 mg/kg sedated the animals but did not produce analgesia or anaesthesia. A combination of ketamine hydrochloride and xylazine at 40 mg/kg and 5 mg/kg, respectively, sedated the animals, but anaesthetic lerels were not attained. Halothane was most effective in producing anaesthesia in Monodelphis domestica. Hypothermia was a major side effect with all three anaesthetic regimes.
Dermal cryptococcosis in a guineapig
Authors: Van Herck H. , Van Den Ingh Th. S. G. A. M. , Van Der Hage M. H. , Zwart P.
Published: May 2007

A case of cryptococcosis in a guineapig with lesions confined to the dorsum of the nose is described. Results of clinical, postmortem and histological examination are discussed. The diagnostic and therapeutic possibilities and problems of cryptococcosis are mentioned.
Megaoesophagus in ICRC mice
Authors: Randelia H. P. , Lalitha V. S.
Published: May 2007

The occurrence of megaoesophagus in ICRC/HiCri mice afforded opportunities to study the genetics and histology of this condition. The anomaly was found to be inherited as a recessive character. Histology indicated abnormality in the myenteric plexus.
Morphology of the terminal bronchiolar region of common laboratory mammals
Authors: Bal H. S. , Ghoshal N. G.
Published: May 2007

The histomorphology of the terminal bronchiolar region of the mouse, rat, hamster, guineapig, gerbil and rabbit was studied. Although some general structural similarities existed in the progressive intrapulmonary branching pattern of the airway tree between species, there were conflicting accounts in the literature about the presence of the respiratory bronchioles in common laboratory mammals. In our light microscopy study we failed to detect the existence of typical respiratory bronchioles with characteristic interruptions on their walls projecting into the alveoli. Frequently in these species the terminal bronchioles were short and abrupt, opening directly into several alveolar ductules.
A shift from acute to chronic spontaneous pyelonephritis in male MM mice associated with a change in the causal micro-organisms
Authors: Taylor D. M.
Published: May 2007

Proteus mirabilis was the predominant cause of acute diabetes-associated pyelonephritis occurring spontaneously in male MM mice until they were segregated in a new environment. Thereafter Pasteurella pneumotropica and Streptococcus faecalis emerged collectively as the most common causal organisms, the pyelonephritis became more chronic and Proteus mirabilis isolates from faeces and urine produced atypical non-swarming colonies on blood agar plates. This did not account for the reduced pathogenicity of Proteus mirabilis; when MM males were returned to the original environment the pyelonephritis again became acute but was associated with the atypical type of Proteus mirabilis although the normal type was abundant in the environment. The MM mice were Caesarian-derived and cross-fostered shortly before their transfer to the second environment, which probably accounts for their changed microbial status, but the reason for the emergence of the atypical type of Proteus mirabilis is not understood. The acute nature of the male MM pyelonephritis when caused by Proteus mirabilis parallels the situation described in other animals and humans.
Altered clinical and histological features of male MM mouse pyelonephritis associated with a change in its microbiology
Authors: Taylor D. M. , Fraser H. , Bruce M. E.
Published: May 2007

Radical changes in the clinical, microbiological and histological features of spontaneous pyelonephritis in MM male mice occurred when they were transferred to a new environment after Caesarian derivation. Although the incidence of pyelonephritis remained the same, the survival age was increased. The renal histology indicated a shift to a more chronic form of pyelonephritis with renal amyloidosis as a common feature. At autopsy much more renal scarring was seen, resulting in the 'shrunken' kidney typical of chronic pyelonephritis. Renal lymphocytic accumulations were commonly found in MM mice, but they were also seen frequently in C57BL mice and in germfree stocks of both strains: no association was found between these lesions and pyelonephritis.
A 2 year follow-up of effects of biotechniques on reproduction in the domestic rabbit, Oryctolagus cuniculus
Authors: Fischer B. , Meuser-Odenkirchen G.
Published: May 2007

Routinely employed reproductive techniques such as gonadotropin treatment (0·3 mg follicle-stimulating hormone (FSH) subcutaneously twice daily for three consecutive days) followed by natural mating or artificial insemination as well as induction of ovulation by human chorionic gonadotropin (hCG) (75 i.u. hCG intravenously) were analysed in the rabbit after 2 years of consecutive experiments. 85% of gonadotropin-treated animals mated spontaneously. All 222 FSH-primed donor rabbits and 59 hCG-injected non-primed controls ovulated. The average number of ovulations per female was 30 (FSH and hCG) and 7·4 (hCG only). The fertilization rate was 88%, and 22·7 embryos were recovered per FSH-treated donor rabbit. With increasing time after mating the embryo recovery rate decreased (day 1 post coitum (p.c.), 36 embryos per rabbit; day 3 p.c., 26 embryos per rabbit; day 5 p.c., 16 embryos per rabbit) and a higher percentage of females had no embryos recovered. Embryo recovery was poor in donors with ovulation numbers greater than 40. Artificial insemination of non-receptive females yielded smaller numbers of embryos compared with natural mating. Differences in fertility between the seasons of the year was revealed to be small.

We conclude that gonadotropin treatment is efficient in increasing the number of embryos. Management of laboratory rabbits (dating, mating and expected number of embryos) is more predictable, and experiments can be performed successfully in all seasons of the year. However, the incidence of embryonic mortality seems to be increased when gonadotropin treatment is applied.
Nutrition and kidney calcification in rats
Authors: Ritskes-Hoitinga J. , Lemmens A. G. , Beynen A. C.
Published: May 2007

Nephrocalcinosis is a 'spontaneous' disorder in rats which refers to the deposition of calcium salts in the kidney, preferably in the corticomedullary region. Studies using defined, semi-purified diets have shown that low dietary concentrations of magnesium, high concentrations of calcium, high concentrations of phosphorus and low calcium: phosphorus ratios induce kidney calcification. Dietary phosphorus induced nephrocalcinosis in female rats is associated with increased kidney size and weight, tubular hyperplasia, fibrosis and increased excretion of albumin in urine. This suggests that nephrocalcinosis may impair kidney function. In rats fed different commercial diets the incidence of nephrocalcinosis can vary considerably. Differences in the degree of nephrocalcinosis in different experiments may negatively influence the comparability of experimental outcome, especially when this is affected by kidney function and structure. Experimental data are needed so that diets can be formulated that do not produce nephrocalcinosis without inducing other disorders.
Calomys laucha (Rodentia, Cricetidae): growth and breeding in laboratory conditions
Authors: Hodara V. L. , Espinosa M. B. , Merani M. S. , Quintans C.
Published: May 2007

The husbandry and breeding of Calomys laucha (Rodentia, Cricetidae) in captivity are described. Growth curves based on body weight and length showed statistical differences between sexes after 45 days, males being heavier than females. The overall reproductive efficiency was 53·4% but birth rate was depressed during winter. Gestation length was 21±1 days and females exhibited postpartum oestrus with a 3-7 day implantation delay (51%). Litter size was 5·3×1·1 ( n=34). Pup survival at weaning was 84·9%. Mean life span in laboratory conditions was 13·5 months and a cumulative mortality of 90% was reached at 27-28 months of age.
Age-related changes in the haematology of female F344 rats
Authors: Turton J. A. , Hawkey C. M. , Hart M. G. , Gwynne J. , Hicks R. M.
Published: May 2007

As little comprehensive baseline data are available on age-related haematological changes in genetically-defined rat strains, the haematology of female F344 rats is described in animals sampled at 2, 4, 8, 20, 66 and 121 weeks of age. Values for Hb, RBC and PCV increased from 2 weeks of age to reach adult levels at 8 weeks, whereas MCV, MCH and reticulocyte counts were high initially but decreased to reach the adult range at 8 weeks. Between 66 and 121 weeks, reticulocyte counts were significantly increased and values for MCHC significantly decreased. Lymphocytes were the predominant white cell type in each age group. The absolute numbers of neutrophils and lymphocytes showed slight variations between 2 and 66 weeks and both cell types increased significantly between 66 and121 weeks. Platelet counts showed no overall age-related trends. Fibrinogen values increased from 2 weeks of age to reach the adult level at 8 weeks. One animal of the 14 sampled at 121 weeks showed changes in the blood, liver and spleen consistent with a diagnosis of lymphoid leukaemia.
Identification of newborn rats by tattooing
Authors: Iwaki S. , Matsuo A. , Kast A.
Published: May 2007

Pups were identified by toe clipping or tattooing the plantar surface of the paws on day 4 after delivery. Their growth, maturation, and reproductive capability were not affected by either identification method. In the toe clipping group, however, the duration until fall in the suspension test was significantly shortened, indicating that this identification method may not be suitable for some behavioural tests. The clipping also disturbs the skeletal investigation of toes and is not recommended from the view point of animal welfare. Palm tattooing, on the other hand, satisfies the fundamental requirements for long-term identification of rats.
Effect of cage population density on plasma corticosterone and peripheral lymphocyte populations of laboratory mice
Authors: Peng X. , Lang C. M. , Drozdowicz C. K. , Ohlsson-Wilhelm B. M.
Published: May 2007

The effect of different population densities of mice per cage on plasma corticosterone, peripheral lymphocytes and specific lymphocyte subpopulations was investigated. The animals were housed in groups of 2, 4 or 8 mice per cage and the blood samples were taken from each animal of these groups on days one, 7 and 14. A significant elevation ( P<0·05) in plasma corticosterone concentration was observed in the group of 8 mice per cage on days one and 7 as compared with those of 2 or 4 mice per cage. The number of peripheral lymphocytes was significantly decreased in the groups of 2 ( P<0·01) and 8 ( P<0·05) mice per cage as compared with the group of 4 mice per cage on day one. A significantly decreased number of lymphocytes ( P<0·01) in the group of 8 mice per cage continued to day 7. There were no significant differences in specific lymphocyte subpopulations observed among these groups. The results of this study suggest that a population density of 4 mice per cage induced minimal stress compared to that induced by the population densities of 2 or 8 mice per cage. Since stress is known to induce alteration in a variety of biological functions, the population density of mice per cage should be considered in the interpretaion of research data.
Magnetic resonance imaging using a clinical whole body system: an introduction to a useful technique in small animal experiments
Authors: Wolf R. F. E. , Lam K. H. , Mooyaart E. L. , Bleichrodt R. P. , Nieuwenhuis P. , Schakenraad J. M.
Published: May 2007

A clinical whole body magnetic resonance imaging (MRI) system with high resolution coils was used to obtain non-invasive images of the living rat. The results demonstrate the feasibility of the set-up and the advantages of this new imaging technique: detailed information, no extra costs, longitudinal studies without killing animals and simple anaesthesia. It is concluded that in small animal experimentation, this use of high resolution coils in whole body magnetic resonance systems may be particularly helpful in establishing effects of experimental procedures. Whenever non-invasive visualization is required, especially in longitudinal animal studies, e.g. biomaterial research or tumour investigation, this use of MRI will offer challenging possibilities.
Subcutaneous administration of HMG-CoA reductase inhibitors in hyperlipidaemic and normal rats
Authors: Joles Jaap , Willekes-Koolschijn Nel , Koomans Hein , van Tol Arie , Geelhoed-Mieras Tini , Crommelin Daan , van Bloois Louis , Krajnc-Franken Magda , Cohen Louis , Griffioen Marieke , Erkelens Willem
Published: May 2007

Recent reports demonstrate a hypocholesterolaemic effect of daily subcutaneous injections of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors in different rat models of hyperlipidaemia. However, this effect is not seen after oral administration of HMG-CoA reductase inhibitors in rats. We found that oral administration of the HMG-CoA reductase inhibitor Simvastatin also had no effect on plasma cholesterol in severely hyperlipidaemic Nagase analbuminaemic rats (NAR). Simvastatin (an apolar compound dissolved in propylene glycol) was infused continuously for 28 days into the subcutis of control Sprague-Dawley rats (SDR) and NAR using an implanted osmotic pump. All doses which were effective in reducing cholesterol in the NAR (reductions up to -60%), reduced apolipoprotein AI but not apolipoprotein B and caused a severe inflammatory reaction in the dermis. Similar toxicity was observed in the SDR. Subcutaneous administration of the vehicle (propylene glycol) did not cause this reaction and did not affect plasma lipids. Administration of Lovastatin in osmotic pumps resulted in a similar inflammatory reaction. Incorporation of Simvastatin into liposomes did not diminish the toxic effect. On the other hand, infusion of Pravastatin (a polar HMG-CoA reductase inhibitor dissolved in isotonic saline) caused no changes in the dermis and had no effect on plasma lipids in NAR or SDR. Liver microsomes prepared from the Pravastatin-treated rats demonstrated a 3- to 4-fold increase in HMG-CoA reductase activity as compared to untreated rats, confirming uptake of the drug. We conclude that continuous subcutaneous administration of the HMG-CoA reductase inhibitors Simvastatin, Lovastatin and Pravastatin for 28 days may not reduce plasma cholesterol in rats by a mechanism which is related to inhibition of HMG-CoA reductase activity in the liver. The decrease of plasma cholesterol effected by subcutaneous infusion of Simvastatin or Lovastatin in NAR coincides with, and may be related to inflammatory changes caused by administering these compounds into the dermis.
Struvite urolithiasis in a B6C3F1 mouse
Authors: Wojcinski Z. W. , Renlund R. C. , Barsoum N. J. , Smith G. S.
Published: May 2007

In a 2 year carcinogenicity bioassay using B6C3F1 mice, one male mouse developed clinical signs near termination of the study, comprising skin sores around the prepuce, penile prolapse and urine scalding. The predominant finding at necropsy was a markedly distended urinary bladder filled with numerous crystallized particles. Microscopically, there was subacute cystitis with marked hyperplasia of the transitional epithelium. X-ray diffraction analysis of the crystals showed a diffraction pattern characteristic of struvite (ammonium magnesium phosphate). The implications of the spontaneous occurrence of bladder stones in rodents on long-term toxicology studies are discussed.
Glycosuria and maternal licking in rats
Authors: Goto Masakatsu , Patrick Zeller W. , Morrison Hurley R.
Published: May 2007

Maternal anogenital licking (MAGL) has been studied to understand the mechanism of maternal behaviour. The present study showed that rats had glycosuria at the concentration of 18-20 mg/dl and glucose was the preference of postpartum rats. MAGL increased on suckling rats separated for 24 h. However, wiping anogenital region attenuated the increase of MAGL. Therefore, glucose preference of postpartum rats may be involved in MAGL.
Spiral bacterium associated with gastric, ileal and caecal mucosa of mice
Authors: Queiroz Dulciene M. M. , Contigli Christiane , Coimbra Roney S. , Nogueira Ana Margarida M. F. , Mendes Edilberto N. , Rocha Gifone A. , Moura Silvia B.
Published: May 2007

A spiral shaped bacterium was seen in smears and histological sections (stained by carbolfuchsin) of gastric, ileal and caecal mucosa as well as in stool smears from mice. A significant correlation between the presence of the spiral bacterium and the occurrence of gastritis was observed but the ileal and caecal mucosa seemed unaffected. The bacterium was Gram negative and grew on BHM and Skirrow's medium, under microaerophilic conditions, at 37°C. Its major biochemical characteristics included positive catalase and oxidase reactions and a rapidly positive urease test. There were 2 or 3 spiral turns per cell and a tuft of up to 12 sheathed flagella on each pointed end. Entwined, braided periplasmic fibrils covered the surface of the cell. This spiral bacterium seemed to be part of the normal intestinal flora but was associated with gastritis.
Effects of urethane, alphaxolone/alphadolone, or halothane with or without neuromuscular blockade on survival during repeated episodes of global cerebral ischaemia in the rat
Authors: Holder D. S.
Published: May 2007

The effect of 4 anaesthetic regimes on blood pressure and survival was investigated during repeated episodes of cerebral ischaemia in the rat induced by diathermy of the vertebral arteries and reversible occlusion of the carotid arteries. The best results were obtained with inspired halothane with neuromuscular blockade and artificial ventilation, followed in order by halothane, intravenous alphaxolone/alphadolone, and intraperitoneal urethane with spontaneous ventilation.
Sex ratio and mortality in a laboratory colony of the common marmoset (Callithrix jacchus)
Authors: Rothe Hartmut , Darms Kurt , Koenig Andreas
Published: May 2007

In a retrospective study sex ratio and mortality were analysed in a captive colony of common marmosets ( Callithrix jacchus). Seven hundred and thirty-five infants in 294 litters (20 singletons, 119 twins, 140 triplets, 14 quadruplets) out of 57 breeding females were evaluated. The sex ratio at birth was 0·95 males: 1·0 females. The frequency of males and females, as well as the sex composition of twins and triplets confirm the assumption of dizygotic twinning in the common marmoset. According to age at death, 9 categories were differentiated, with perinatal mortality being the highest. Once early infancy had passed the probability of a common marmoset infant of our colony reaching childhood is nearly 95%. Sixty per cent of all live-born infants survived beyond 18 months. Morta1ity of infants at birth from primiparous mothers did not differ from that of pluriparous females, nor did the survival rate of infants with the filial generation the respective female had reached (F1 to F6). Females with a high ratio of triplets and quadruplets had a lower reproductive success than females with a majority of singleton or twin deliveries. Differential mortality between males and females was not observed. The frequency of stillbirths was not strongly related to parity, but was to litter-size. Most stillborn babies were seen in sets of quadruplets, most abortions in singletons. A normal socialization in a stable social environment, as well as not pairing the animals before they are fully adult, are considered important factors in good breeding success and infant survival.
A simple gag for the intragastric dosing of guineapigs (Cavia porcellus)
Authors: Smith Barry L. , Flåøyen Arne , Embling Peter P.
Published: May 2007

A simple gag has been designed and tested which enables the intragastric intubation of the guineapig by one person without the use of sedation or light anaesthesia. The system described was used successfully for the daily dosing of materials to 7 guineapigs for 14 days without discomfort, aspiration or any injury to the upper gastro-intestinal tract.
A comparison of propofol with other injectable anaesthetics in a rat model for measuring cardiovascular parameters
Authors: Brammer A. , West C. D. , Allen S. L.
Published: May 2007

Prolonged, stable, non-recovery anaesthesia is required for the assessment of the effects of novel compounds on the cardiovascular system. A comparison of injectable anaesthetic agents and combinations (thiobarbital, fentanyl-fluanisone and midazolam, propofol, fentanyl-fluanisone and propofol, and alphaxalone/alphadolone) was made in laboratory rats and the following parameters assessed over 3 h: blood pressure, heart rate and rhythm, respiration rate and depth, analgesia, ease of induction and maintenance of anaesthesia. It was found that propofol, with fentanyl-fluanisone premedication, provided stress-free induction, easily controlled anaesthesia, good analgesia and muscle relaxation for surgery, for up to 3 h duration. Heart rate, blood pressure and respiration remained stable and within normal limits during this time. The other anaesthetics/combinations assessed did not rate as highly in these respects. Propofol, following fentanyl-fluanisone premedication, would appear to be a useful and safe anaesthetic for use in rodents, which avoids significant effects on heart rate or blood pressure.
Induction of oestrus in cats by photoperiodic manipulations and social stimuli
Authors: Michel Chantal
Published: May 2007

The development of the nervous system can be studied only if the age of the embryo is exactly known. Since it is difficult to control reproduction in female cats, we tried to time fertilization very precisely to within one hour by using either artificial insemination, or by mating females in oestrus induced by light programming. In one trial, this programming was associated with male or female stimuli according to the work of McClintock (1971, 1978, 1984) and Preti et al. (1986).
Induction of alloxan/streptozotocin diabetes in dogs: A revised experimental technique
Authors: Anderson H. R. , Stitt A. W. , Gardiner T. A. , Lloyd S. J. , Archer D. B.
Published: May 2007

The diabetic dog represents an excellent model for use in many aspects of diabetic research. The present paper describes, in detail, a reproducible experimental protocol for the successful induction of chemical diabetes in beagles using a combination of the 2 pancreatic beta-cell cytoxic agents alloxan and streptozotocin.
Evaluation of the Clinitek 200 urinary test-strip reader in the analysis of dog and rat urines in pre-clinical toxicology studies
Authors: Paquignon A. , Tran G. , Provost J. P.
Published: May 2007

The performance of a clinical urinary test-strip reader Clinitek 200 was evaluated for dog and rat urines, in the context of pre-clinical toxicology studies. No major discrepancies were found between data generated by visual estimation or automatic measurement. Analysis of spiked samples showed good agreement between actual concentrations and Clinitek 200 responses for ketone bodies and glucose although a lack of sensitivity was found for the latter. Results for proteins showed over- or underestimation in dog and rat urines respectively at low concentrations, and overestimation at high concentrations in both species. Reproducibility of responses was excellent for ketone bodies, glucose and proteins but was weaker for haemoglobin and bilirubin. High bilirubin concentrations were found to interfere with the haemoglobin reaction. The pH measurements were found to be accurate only around pH 7. Specific gravity measurements were unreliable. Overall, the Clinitek 200 as a screening tool proved sufficiently reliable in the measurement of all parameters tested, with the exception of specific gravity.
Whisker trimming behaviour in A2G mice is not prevented by offering means of withdrawal from it
Authors: Van Den Broek F. A. R. , Omtzigt C. M. , Beynen A. C.
Published: May 2007

In group-housed laboratory mice whisker trimming (removal of vibrissae) occurs occasionally, but in the A2G strain it is seen almost invariably. We have tested the hypothesis that whisker trimming in A2G mice is not prevented by offering the possibility to withdraw from it. Pairs of male or female mice showing absence of whiskers and/or absence of nasal fur were separated by placing in their cage either one or two wire screens with a 10 mm mesh. Unlike the single screen, the two screens, which were 10 mm apart from each other, excluded nose to mouth contact. After five weeks, whiskers had regrown in mice separated by the double screen, whereas in the pairs separated by the single screen whiskers remained in part absent. This suggests that 2 mice involved in whisker trimming, either actively or passively, co-operate in this behaviour.
Transmissibility of the D variant of encephalomyocarditis virus (EMC-D) in mice
Authors: Doi Chiyo , Takeda M. , Hirasawa K. , Doi K.
Published: May 2007

Transmissibility of the D variant of encephalo-myocarditis virus (EMC-D) was examined. Eight-week-old ICR:CD-1 male mice inoculated with 105 plaque forming units (PFU)/animal of EMC-D intranasally, orally or intraperitoneally showed marked viraemia and prominent pancreatic lesions at 2 days after inoculation (2 DAI), and excreted virus in faeces from 2 to 8 DAI (virus titre:l03-l05 PFU/g). Only a small proportion of control mice housed with EMC-D-inoculated mice for 10 days developed viraemia and pancreatic lesions.
A spontaneous outbreak of Theiler's encephalomyelitis in a colony of severe combined immunodeficient mice in the UK
Authors: Rozengurt N. , Sanchez S.
Published: May 2007

Severe Combined Immunodeficient (SCID) mice lack both T and B lymphocytes which makes them highly susceptible to infectious agents. In the present communication, we describe an outbreak of Theiler's encephalomyelitis in a colony of SCID mice which was characterized by an unusually high prevalence of clinically overt cases. Diagnosis was based on the clinical signs, histological lesions and presence of antibodies in contemporaneous immunocompetent mice. This is the first report of this disease in SCID mice and, to our knowledge, also the first reported outbreak of Theiler's encephalomyelitis in the UK.
Mammary tumour induction by pituitary grafting in male mice: An animal model for male breast cancer
Authors: Nagasawa H. , Morii S. , Furuichi R. , Iwai Y. , Iwai M. , Mori T. , Goto Y.
Published: May 2007

Isologous anterior pituitary grafting, 4 each, to 3-4-month-old SHN and SLN male mice resulted in an appearance of mammary tumours from 8 months of age and the incidence at 12 months reached 53·8% in each strain. All tumours were diagnosed as type B adenocarcinomas. In association with the results, normal mammary gland growth and mouse mammary tumour virus (MMTV)-gp52 antigen levels in the submaxillary glands were stimulated by the treatment in these strains. The effect of pituitary grafting was much less in GR/A male mice in which no mammary tumours appeared.
A simple technique for blood collection in the pig
Authors: Hu C. , Cheang A. , Retnam L. , Yap E. H.
Published: May 2007

A simple technique for blood collection in pigs of body weight 15-40 kg is described. The subcutaneous abdominal vein was used for rapid collection of 5-20 ml of blood samples. The animals were premedicated with 10 mg/kg of ketamine and 600 μg of atropine given intramuscularly prior to blood collection.
The effects of group housing on the research use of the laboratory rabbit
Authors: Whary Mark , Peper Randall , Borkowski Gary , Lawrence Wendy , Ferguson Frederick
Published: May 2007

This project evaluated the influence of group housing on common aspects of research use of female laboratory rabbits ( Oryctolagus cuniculus). Eight rabbits housed individually in conventional cages were compared to a second group of 8 housed as a social group in a proportionately larger enclosure. The group housing method provided increased opportunities for exercise, social contact, and a more novel environment. As a function of housing style, the 2 experimental groups were compared on humoral and delayed hypersensitivity response, feed intake, growth rate, and selected physiological parameters that are considered to reflect stress in most species. Single and group housed rabbits did not significantly differ in physiological and immunological measurements, indicating that the practical research performance (immune response, stress level, growth rates etc.) of these rabbits was not significantly affected by group housing compared with the more traditional single housing. Analysis of group social behaviour indicated that the rabbits preferred small social groups, had preferences for microenvironments within the enclosure, and exhibited behaviours that are not possible when housed singly. Group housing appeared to be a successful method for enriching the environment of female rabbits and aspects of it should be considered in the approach to housing rabbits used in research.