bluuebunny/crossref_metadata_2025 huggingface dataset:
Isolation and identification of clostridia from the intestine of laboratory animals
Authors: Lee W. K. , Fujisawa T. , Kawamura S. , Itoh K. , Mitsuoka T.
Published: May 2007

Quantitative and qualitative examination of faecal clostridia from laboratory mice, rats, hamsters and rabbits was carried out by using selective as well as nonselective culture techniques. The 364 isolates were identified where possible, to species level on the basis of physiological and biochemical characteristics. Most isolates from mice and rabbits were identified, i.e. 79·4% and 76·5%, respectively, while only 25·4% and 28·6% of isolates from rats and hamsters were characterized as described species. The most common species of the 16 identified were: C. coccoides, C. cocleatum and C. innocuum from mice; C. cocleatum, C. cochlearium and C. irregularis from rats; C. cocleatum and C. irregularis from hamsters; and C. aminovalericum and C. irregularis from rabbits. Unidentified Clostridium spp. were isolated from each animal species tested and were tentatively classified into 26 groups. None of these groups was found in more than one animal species in this study.
Indirect systolic and mean blood pressure determination by a new tail cuff method in spontaneously hypertensive rats
Authors: Ikeda K. , Nara Y. , Yamori Y.
Published: May 2007

A new tail cuff method for determining systolic and mean blood pressure in rats was developed based on photoelectric detection of tail arterial blood flow and pulsatile volume oscillation. Indirect systolic and mean blood pressure measured by this method correlated well with direct systolic and mean blood pressures recorded by a transducer and polygraph after carotid artery cannulation in stroke-resistant spontaneously hypertensive rats (SHR), stroke-prone SHR and normotensive Wistar Kyoto rats. Blood pressures were sharply, and transiently raised for about 1 min when rats were picked up by an investigator to be placed in a hot box or immobilized in a restrainer for measuring blood pressure. Therefore, blood pressures should be measured at least 1 min after the rats are put in a restrainer. This new tail cuff method for measuring blood pressure provides reliable mean blood pressure readings in conscious rats.
Incomplete proviral genome of mouse mammary tumour virus is present on chromosome Y of NIH Swiss and some genetically related mouse strains
Authors: Nishikawa R. , Okumoto M. , Iwai M. , Iwai Y. , Takamori Y. , Imai S. , Hilgers J.
Published: May 2007

An incomplete proviral genome of endogenous mammary tumour virus (MMTV) was found in DNA of several strains of mice. This MMTV-related sequence was assigned to the Y chromosome since it was clearly observed in male mice only. This MMTV provirus contained a sequence related to LTR (long terminal repeat), but not to gag-pol and env genes. NFS, NIH Swiss/S, STS/A, and DD/Tbr mice have this sequence but BALB/cHeA, SHN, SLN, C57BL/6NJcl, C3H/HeNJcl and CBA/JJcl mice are negative. In the strains containing this sequence, a DNA test for the sequence makes it possible to easily distinguish the DNAs of male or female mice.
Quantification and classification of pregnancy wastage in 5-day cyclic young through middle-aged rats
Authors: Mattheij J. A. M. , Swarts J. J. M.
Published: May 2007

Fecundity was quantified in 4 to 11-month old rats with regular 5-day cycles. On the day following mating, less than 5% luteinized unruptured follicles occurred in either 4-month old or 11-month old rats; ovulation rate and also fertilization rate were similar in these young and middle-aged rats. At day 19 of pregnancy embryonic and fetal mortalities were quantified. Pregnancy wastage increased gradually with age; it was already significant in 7-month old rats. In rats of 9 months old it was about 30% and in 11-month old rats it was greater than 65%. Pregnancy wastage was mainly due to preimplantation and early-postimplantation mortality. Pregnancy wastage did not decrease when the pre-ovulatory surge of luteinizing hormone (LH) was reinforced and timed, by injection of the LH-releasing hormone analogue Ovalyse at noon on the day of prooestrus. The results corroborate the idea that pregnancy wastage in middle-aged rats with regular cycles is caused by an age-related reduction of the viability of ovulating eggs.
Isolation of Streptobacillus moniliformis from the middle ear of rats
Authors: Koopman J. P. , van den Brink M. E. , Vennix P. P. C. A. , Kuypers W. , Boot R. , Bakker R. H.
Published: May 2007

Streptobacillus moniliformis was isolated from the middle ear of 9 of 16 rats used for otological studies. Examination of rat sera for the presence of anti- Streptobacillus moniliformis antibodies using an ELISA technique resulted in 15 seropositive animals. The source of the S. moniliformis infection was not determined.
Isolation of blood granulocytes from golden hamsters for the study of chemotaxis
Authors: Spanel-Borowski K.
Published: May 2007

Since the number of granulocytes is low in the circulating pool of adult golden hamsters, intraperitoneal injection of oyster glycogen was used to mobilize white blood cells from the noncirculating pool. The percentage of blood granulocytes increased from 7 to 49%. Mobilized granulocytes, purified by a discontinuous Percoll gradient, showed adherence to polycarbonate filters only when coated by collagen. Random migration was high using the modified Boyden chamber technique. While endotoxin-activated serum caused chemotactic response, it was absent when the tripeptide N-formyl-methionyl-leucyl-phenylalanine was applied at concentrations of 10-7 or 10-8 M. The true chemotactic response corresponded to the proportion of migrated cells versus the total cell number adherent to both sides of the filter. It is concluded that the golden hamster is a good model for the study of granulocyte sequestration.
The effects of surgical procedures, halothane anaesthesia and nalbuphine on locomotor activity and food and water consumption in rats
Authors: Flecknell P. A. , Liles J. H.
Published: May 2007

A study was undertaken to investigate the effects of surgical procedures on food and water intake and spontaneous locomotor activity in laboratory rats. The influence of anaesthesia with halothane and administration of the opioid analgesic nalbuphine was investigated in normal rats and in animals which underwent either unilateral nephrectomy or jugular vein cannulation.

Both nephrectomy and jugular cannulation were associated with a significant reduction in food and water consumption and a depression in locomotor activity levels. The reduction in activity following nephrectomy was reversed by administration of 6 doses of nalbuphine at 4 hourly intervals. Administration of nalbuphine at the same dose rate following halothane anaesthesia in normal rats resulted in a stimulation of activity. The prevention of the depressant effects of surgery by this opioid appears to be due to its stimulatory effect rather than a specific analgesic action. The degree of depression of food and water consumption after nephrectomy was significantly reduced following 6 doses of nalbuphine. This beneficial effect of repeated administration of an opioid may be related to the compound's analgesic action.
Quantitative studies of haematological values in long-term ovariectomized, ovariohysterectomized and hysterectomized rats
Authors: Kuhn G. , Hardegg W.
Published: May 2007

The effects of ovariectomy, ovariohysterectomy and hysterectomy on total and differential white blood cell counts, distribution of T and B lymphocytes and T/B cell relationship were studied. Changes in these parameters associated with the surgical operations were observed in total leukocytes and lymphocytes, absolute and relative band neutrophils and T/B cell relationship. Results suggest that the ovaries together with the uterus are potential regulatory organs upon the absolute number of circulating leukocytes and lymphocytes in female Lewis rats. In addition to their effects upon this important population of cells, the ovaries and uterus have moderate effects upon relative T and B lymphocyte numbers in peripheral blood. In general the changes depend mainly on the removal of the ovaries and to a lesser degree on hysterectomy.
A protective thermoplast splint for the forearm and hand in nonhuman primates
Authors: Hovius S. E. R. , Stevens H. P. J. D. , Peters B. , van Nierop P. W. M.
Published: May 2007

A custom-made thermoplastic splint was developed for the protection of the upper extremity after experimental surgery. It was used in 39 cases for a duration of 12-79 days. Complications were minimal and transient. The cast was easy to make, in one piece and inexpensive. Frequent removal for wound inspection was simple. This splint provides a good immobilization and protection of the arm and hand in the nonhuman primate.
Ambulatory electrocardiography (Holter monitoring) in caged monkeys
Authors: Vogel A. P. , Jaax G. P. , Tezak-Reid T. M. , Baskin S. I. , Bartholomew J. L.
Published: May 2007

A swivel-tethering and jacket system was used in conjunction with vinyl patch electrodes and Holter recorders to obtain continuous ECG recordings in 12 rhesus monkeys on a long-term (12 day) study. Animals were custom-fitted with nylon mesh jackets that were connected to a swivel unit by a flexible, stainless steel tether. Lead wires from the chest electrodes passed through the tether to the electrical swivel apparatus located at the top of the cage. Wires from the upper part of the swivel were attached to a reel-to-reel Holter recorder. This technique was used to obtain 24-h continuous ECG recordings, which were later processed using a computer-assisted Holter analysis system.
Population distribution profiles of the activities of blood alanine and aspartate aminotransferase in the normal F344 inbred rat by age and sex
Authors: Waner Trevor , Nyska Abraham , Chen Rina
Published: May 2007

Data on the blood enzyme activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were collected from control male and female F344 rats participating in toxicity studies at 17, 30, 56, 80 and 106 weeks of age. The data were skewed to the right with significant deviation from normality. Applying the Box-Cox transformation, it was concluded that approximately normal distributions could be obtained by using the reciprocal transformation. In general, the males showed a greater degree of heterogeneity for both enzymes. Enzyme activities at 17 weeks were lowest for both ALT and AST. There was a high correlation between the activities of blood ALT and AST, with some animals showing dramatic transient increases. Significant differences among studies with respect to the enzyme activities in rats of the same age were demonstrated.
A case of muItiloculated, intracranial epidermoid cyst in a beagle dog
Authors: Kawaminami A. , Tawaratani T. , Nakazawa M. , Uchimoto H. , Sumi N.
Published: May 2007

An intracranial epidermoid cyst was identified within the fourth ventricle of a male 10-month old beagle dog. The cyst, which exhibited a multilocular structure, was lined by a stratified squamous epithelium and filled with desquamated keratin. In the region of the roof of the fourth ventricle, choroid plexus adherent to the cyst wall and secondary compression of the cerebellum were also seen.
Ontogeny of absence-like and tonic seizures in the spontaneously epileptic rat
Authors: Serikawa Tadao , Yamada Junzo , Ujihara Hisamitsu , Ohno Yukihiro , Sasa Masashi , Takaori Shuji
Published: May 2007

The ontogeny of epileptic seizures in spontaneously epileptic rats (SER; zi/zi, tm/tm) was studied by examining behaviour and electroencephalogram (EEG) simultaneously. Weight gain and survival time were also studied. Compared with the control Kyo:Wistar rats, SER showed a much smaller increase in body weight. All male and female SER died before 20 and 18 weeks of age, respectively. Body tremor was observed at 2 weeks of age but disappeared after 11 weeks. Staggering gait appeared after 7 weeks of age, and intensified with age. Absence-like seizures characterized by paroxysmal appearance of 5-7 Hz spike-wave-like complexes were observed in the cortical or hippocampal EEG after 5 weeks of age, and tonic seizures with low voltage fast waves were observed after 6 weeks of age. All SER exhibited both absence-like and tonic seizures with high frequencies from 12 weeks of age. Differences with other spontaneous rat models of epilepsy and application methods for estimating seizure-inhibitory effects of anti-epileptic drugs are discussed.
Phosphorus-induced nephrocalcinosis in female rats: a study on regression and clinical abnormalities
Authors: Soeterboek S. J. A. J. , Ritskes-Hoitinga J. , Lemmens A. G. , Beyneni C.
Published: May 2007

The question addressed was whether pre-established phosphorus (P)-induced nephrocalcinosis would regress after dietary P restriction. Female rats were fed purified diets containing either 0·2% (w/w) P(low P) or 0·6% P (high P). After 29 days, the high-P diet had caused massive nephrocalcinosis as demonstrated chemically (by the analysis of calcium in kidney) and histologically Jby inspection of kidney sections stained for calcium phosphate deposits). Switching rats from the high P to the low P diet did not result in a decrease in the degree of nephrocalcinosis within 91 days. Thus, P-induced nephrocalcinosis may not regress upon subsequent P restriction. Rats that had been fed either the 0·2 or 0·6% P diet for 56 days were examined clinically with respect to 14 selected variables. None of the variables discriminated between rats with or without nephrocalcinosis. This might imply that P-induced nephrocalcinosis in female rats does not cause significant discomfort.
Why modification of the LD50 test will not be enough
Authors: Balls M.
Published: May 2007

During the last 10 years, the 'Three Rs' (reduction, refinement and replacement) concept of alternatives has come to be widely accepted, and new national and international laws require that non-animal procedures should replace animal experimentation wherever possible. Some reduction and refinement of animal use in toxicity testing has been achieved, and non-animal methods are becoming widely used as prescreens. However, even replacing the LDSO test by a modified and validated animal test, the Fixed Dose Procedure, will be a major achievement. In this paper it is argued that this is not good enough, and that more effort must be put into the development, validation, acceptance and use of genuine replacement alternative tests.
Segregation of genes from donor strain during the production of recombinant congenic strains
Authors: Van Zutphen L. F. M. , Den Bieman M. , Lankhorst A. , Demant P.
Published: May 2007

Recombinant congenic strains (RCS) constitute a set of inbred strains which are designed to dissect the genetic control of multigenic traits, such as tumour susceptibility or disease resistance. Each RCS contains a small fraction of the genome of a common donor strain, while the majority of genes stem from a common background strain. We tested at two stages of the inbreeding process in 20 RCS, derived from BALB/cHeA and STS/A, to see whether alleles from the STS/A donor strain are distributed over the RCS in a ratio as would theoretically be expected. Four marker genes (Pep-3; Pgm-1; Gpi-1 and Es-3) located at 4 different chromosomes were selected and the allelic distribution was tested after 3-4 and after 12 generations of inbreeding. The data obtained do not significantly deviate from the expected pattern, thus supporting the validity of the concept of RCS.
Stability of pathogenic bacteria from laboratory animals in various transport media
Authors: Shimoda K. , Maejima K. , Kuhara T. , Nakagawa M.
Published: May 2007

The stability of pathogenic bacteria from laboratory animals was investigated in various transport media at different temperatures. Bordetella bronchiseptica and Salmonella typhimurium survived for 8 days in phosphate-buffered saline (PBS, pH 7·0) at 37, 24, 4 and -20°C; Brucella canis at 24, 4 and -20°C; Corynebacterium kutscheri at 4 and -20°C; and Pseudomonas aeruginosa at all but -20°C. A marked decrease in numbers of Pasteurella multocida and Past. pneumotropica was observed in PBS at all temperatures. Skimmed milk in PBS improved the survival of Pasteurella spp. and Ps. aeruginosa at -20°C. Neither glycerin, ascorbic acid nor sodium thioglycollate improved survival. The numbers of viable B. canis, Ps. aeruginosa and S. typhimurium were maintained in blood or faecal specimens held for 8 days at 4°C. These results indicated that transport in PBS at 4°C was the only method satisfactory for all species of pathogenic organisms tested, but Pasteurella spp. were the most difficult to maintain.
Morphometrical changes in the apical surface of the colonic absorptive cells in perinatal rats with special reference to the effect of fetal oral administration of milk in utero
Authors: Morikawa Yoshio , Fujimoto Kaori , Okada Toshiya
Published: May 2007

Perinatal changes in the apical surface of the colonic absorptive cells in the rat were studied morphometrically. Cell microvilli length increased from day 20 through neonatal day 3, during which a maximum incremental growth rate was noted between fetal day 22 and neonatal day 1. Microvilli width remained almost constant throughout the period. Enlargement of the apical surface of the microvilli showed a similar developmental pattern as was seen from the measurement of length and surface area of any one of the microvilli. Fetal oral administration of milk in utero caused incremental growth in length and surface area, as well as an associated apical surface enlargement. The present study indicates that the function of the colonic absorptive cells, which is acquired later on in utero, is activated by ingestion of maternal milk after birth.
A simple device for the objective measurement of activity
Authors: de Chalain T. M. B. , Whitfield D.
Published: May 2007

The activity of small experimental animals is difficult to quantify without prolonged observation and note-taking. We describe a relatively cheap and easily constructed device for monitoring and recording activity. Appropriate modifications make the basic device suitable for limited field applications.
Naturally acquired Pasteurella multocida subsp. multocida infection in a closed colony of rabbits: characteristics of isolates
Authors: Digiacomo Ronald F , Allen Vivien , Hinton Michael H
Published: May 2007

Twelve litters, comprising 41 rabbits aged 35 to 60 days old, in a closed university colony, were monitored for acquisition of nasal Pasteurella multocida subsp. multocida infection. Isolates from 11 infected rabbits were characterized by colonial morphology, capsular type, biotype and antibiotic resistance. Selected isolates were further characterized by somatic antigen typing. Two major strains of P. multocida subsp. multocida were detected in the colony. One strain had mucoid colonies, fermented few carbohydrates and was serotype A:5, whereas, the other strain had smooth iridescent colonies, non-typeable capsular antigen, type 3 somatic antigen and fermented more than twice as many carbohydrates.
The effects of diet on the incidence of periodontitis in rats
Authors: Robinson M. , Hart D. , Pigott G. H.
Published: May 2007

Four groups of 60 male Alpk:APfSD rats were fed different nutritionally comparable diets for 107 weeks with interim sacrifices at 26, 53 and 77 weeks in order to compare the effect of diet on the incidence of oral disease. Changes in the oral and nasal cavities were assessed by histopathology. Oro-nasal fistulation and severe periodontitis were associated with diets containing fibres originating from oats and barley. An expanded ground diet induced the most severe lesions. Aspects of the pathogenesis of the lesions observed are discussed.
A bone biopsy procedure for neonatal pigs
Authors: Bobilya Dennis J. , Maurizi Michael G. , Veum Trygve L. , Allen William C.
Published: May 2007

Neonatal pigs were used to develop a surgical biopsy procedure to remove bone tissue from the ilium of small animals, with potential application for infants and small children. While the neonatal pig was under general anaesthesia, a scalpel was used to make a punch incision down to the ilium. Then a Craig Biopsy Trephine was used to remove a core sample of the bone. The samples ranged from 5 to 15 mm in length and 2 to 3 mm in diameter, with an average dry weight of 34·4 mg. The samples were adequate for mineral (calcium and zinc) analysis in our laboratory and may be equally suitable for histological or biochemical analyses. Surgical trauma was minimal, which permitted each pig to be biopsied every 7 days for 5 weeks without adverse consequences.
A percutaneous liver biopsy technique in ducks (Anas platyrhynchos) experimentally infected with duck hepatitis B virus
Authors: Varagona G. , Ellis L. A. , Moore D. , Penney D. , Dusheiko G. M.
Published: May 2007

Aylesbury ducks ( Anas platyrhynchos) chronically infected with the duck hepatitis B virus provide a useful model for studying hepadnavirus infection, replication and the effects of antiviral therapy. In these studies, it is necessary to have an effective method for obtaining repeat liver specimens for histological and molecular analyses. We have therefore developed a percutaneous liver biopsy technique which has a low rate of complications, can be performed at repeated intervals, and provides sufficient quantities of liver tissue for histological and nucleic acid hybridization analysis.
Age of pairing affects reproduction in prairie voles
Authors: Solomon Nancy G.
Published: May 2007

The effect of the age at pairing on reproduction of weanling prairie voles was studied. The proportion of pairs producing a litter within 60 days was influenced significantly by the age at pairing. More voles paired at 31 days of age produced litters than those paired at 21 days of age. Assuming a gestation interval of 21 days, the earliest mating occurred around 33 days of age in both groups. On average, successful matings did not occur until voles were housed together for 2 to 3 weeks. No other measured variables were affected by age of pairing.
Genetic variation within and between lines of diabetes-prone and non-diabetes-prone BB rats; allele distribution of 8 protein markers
Authors: Prins J. B. , Herberg L. , Den Bieman M. , Van Zutphen L. F. M.
Published: May 2007

Twenty-four inbred and 2 outbred lines of the BB rat have been genetically characterized by establishing the allele distribution of 8 monogenic protein markers. The marker genes are: plasma alkaline phosphatase-1 ( Alp-1), catalase-1 ( Cs-1), carboxylesterases ( Es-1, Es-2, Es-14), glyoxalase I ( Glo-1), group specific component ( Gc), and haemoglobin-β-chain ( Hbb). At least 3 linkage groups are represented by this set of markers. Genetic variation was found both within and between lines. Within-line variation was observed in 4 lines, including the 2 outbred lines. The other 22 lines could be subdivided into 4 groups, each representing a unique allele distribution pattern.
Toxicity of anticancer agents, growth and chemosensitivity of human tumour xenografts in a segregating stock of AF nude mice
Authors: Maruo Kohji , Emura Reiko , Ohnishi Yasuyuki , Endo Sachio , Ueyama Yoshito , Nomura Tatsuji
Published: May 2007

An investigation of the usefulness of a segregating stock of nude mice [AF nude mice (AF- nu)] for screening anticancer agents was undertaken. The toxicity of anticancer agents, takes and growth rates of human tumour xenografts and chemosensitivities of xenografts in AF- nu were studied and compared with those in BALB/cA nude mice (BALB/cA- nu). The results showed differences in the pattern of mortalities of AF- nu and BALB/cA- nu administered a range of anticancer agents. Body weight changes in the two nude mouse strains differed in the case of 5-fluorouracil, but not for nimustine, adriamycin and vincristine. All tumours transplanted in AF- nu grew as in BALB/cA- nu. Growth rates of 2 xenografts (gastric cancer and glioblastoma) were not significantly different between the 2 nude mouse strains, but those of 2 lung tumour xenografts were significantly greater in AF- nu than those in BALB/cA- nu. There were no significant differences in chemosensitivities of human tumours in AF- nu and BALB/cA- nu (consistency rate as evaluated by our criteria was 88%). From these results, it is suggested that AF- nu are more suitable for anticancer agent screening and experimental chemotherapy of human tumour xenografts than BALB/cA- nu because of lower costs and high reproductive rate. Although they are genetically heterogeneous, sets of experimental animals sharing the same gene pool can be produced routinely.
Endocrine stress response in rats subjected to singular orbital puncture while under diethyl-ether anaesthesia
Authors: Van Herck H. , Baumans V. , De Boer S. F. , Van Der Gugten J. , Van Woerkom A. B. , Beynen A. C.
Published: May 2007

In an attempt to assess possible discomfort in rats subjected to orbital puncture while under diethylether anaesthesia, their endocrine stress response was determined. Concentrations of corticosterone, adrenaline and noradrenaline were measured in plasma obtained via a jugular catheter from rats subjected to diethyl-ether anaesthesia with or without orbital puncture. No statistically significant differences were found between the punctured and non-punctured rats as to peak levels of plasma corticosterone and adrenaline as well as for the times required by the increased concentrations to return to baseline values. The rate by which the plasma noradrenaline level returned to baseline values was somewhat decreased by orbital puncture. Diethyl-ether anaesthesia alone produced a marked endocrine response when compared with handling and novelty stress associated with the induction of anaesthesia. It is concluded that diethyl-ether anaesthesia causes pronounced increases in the plasma levels of the selected stress hormones and that orbital puncture does not amplify this response. It is suggested that diethyl-ether anaesthesia masks any effects of orbital puncture.
A simple method for the intragastric administration of drugs to fully conscious guineapigs
Authors: de Brant Veerle , Remon Jean Paul
Published: May 2007

The design and use of a simple system for the intragastric administration of miniature capsules or fluids to fully conscious guineapigs is described. The system is suitable for repeated drug administration. It causes minimal discomfort to the animals.
Factors affecting the food intake, growth and protein utilization in the Helix aspersa snail. Protein content of the diet and animal age
Authors: Sampelayo M. R. Sanz , Fonolla J. , Extremera F. Gil
Published: May 2007

Food intake, growth and protein utilization were studied in the Helix aspersa snail by means of a nutritional balance experiment. This was designed in a 5·11 factorial arrangement involving 5 diets of different protein content (10·0, 12·5, 15·0, 17·5 and 20·0%) and 11 animal ages (ranging over 15 to 180 days of age). Dietary protein content and animal age determined food intake and protein utilization. The variations of dry matter and protein intake rates, growth rates, growth effeciency factors and protein retention rates, depending on dietary protein content or animal age were in agreement with what happens in other animals. These results suggest that there is no need to use diets with more than 17·5% of crude protein in these animals.
In-vivomonitoring of corticomedullary nephrocalcinosis in rats using computerized tomography
Authors: Grimm P. , Nowitzki-Grimm S. , Weidenmaier W. , Schumacher K. A. , Classen H. G.
Published: May 2007

An in-vivo method, computerized tomography (CT), was used to monitor nephrocalcinosis in female rats. CT density data correlated well with renal Ca content measured by atomic absorption spectrophotometry.

In-vivo CT measurements revealed that the severity of nephrocalcinosis may change spontaneously with time. Manifest calcifications may exhibit spontaneous regression and are probably affected positively by high dietary Mg, in contrast to increased Ca. It is concluded that CT is a suitable and reliable non-invasive in vivo method to follow up time-dependent alterations in kidney calcifications in rats.
Mandible shape analysis in Y-congenic strains of mice
Authors: Moutier R. , Earlier M.
Published: May 2007

In order to test for the presence of genes influencing morphology on the Y-chromosome of mice, a canonical discriminant analysis of variation in mandible shape was conducted in 4 inbred strains of mice and 4 Y-chromosome congenic partners. Genetic background-dependent differences were observed, as well as a small sex variation in some strains, but it was impossible to detect any difference related to the between-strain exchange of the Y-chromosome.
The isolated, buffer-perfused ferret heart: A new model for the study of cardiac physiology and metabolism
Authors: Neubauer Stefan S.
Published: May 2007

The isolated, buffer-perfused ferret heart is a new model for the study of cardiac physiology and metabolism. Compared to the more commonly used isolated heart preparation, the rat heart, the ferret has a lower rate-pressure product due to lower heart rate, a remarkably low coronary flow and almost complete oxygen extraction. The ferret heart remains in stable haemodynamic and metabolic conditions for a longer period of time than the rat heart. ATP contents of the two species are similar, but creatine phosphate content is higher in the ferret while NAD content is much lower.
Vitamin D, within its range of fluctuation in commercial rat diets, does not influence nephrocalcinogenesis in female rats
Authors: Marsman G. , Pastoor F. J. H. , Mathot J. N. J. J. , Theuns H. M. , Beynen A. C.
Published: May 2007

Massive, toxic doses of vitamin D have been shown to cause nephrocalcinosis in rats, but the effect of this vitamin within its range of fluctuation in commercial rat diets was unknown. Therefore, in two experiments with young female rats, the effect on nephrocalcinosis of a moderately increased level of vitamin D in the diet was studied, that is 5000 IU/kg versus the recommended concentration of 1000 IU/kg. This was done using purified diets with 0·5% (w/w) calcium and 0·04% magnesium containing either 0·2 or 0·06 phosphorus (P). Rats fed the diets containing 0·06%P showed severe kidney calcification compared to those fed the 0·2%-P diets. The level of vitamin D in the 0·2 and 0·6%-Pdiets did not affect kidney calcification. Bone density was increased after feeding diets containing 5000 instead of 1000 IV of vitamin D/kg. This study suggests that, within 28 days, a moderate increase of the amount of vitamin D in the diet has no influence on the development of kidney calcification. This in turn suggests that the variation in nephrocalcinosis severity and incidence seen in practice in rats fed different commercial diets is unlikely to be related to the different vitamin D concentrations in these diets. However, in rats fed such diets bone metabolism may be influenced differently.
Spontaneous uterine granular cell tumour in a Fischer 344 rat
Authors: Nyska A. , Pirak M. , Shahar A. , Scolnik M. , Waner T.
Published: May 2007

The microscopic features of a spontaneous uterine granular cell tumour in a Fischer 344 rat are described. The location of the tumour is novel for the rat. The neoplasm is characterized by the presence of cells with cytoplasmic granules which were PAS positive and diastase resistant. Electron microscopy and immunohistochemistry results are presented and the origin of the tumour is discussed.
Post-operative analgesia following thoracotomy in the dog: an evaluation of the effects of bupivacaine intercostal nerve block and nalbuphine on respiratory function
Authors: Flecknell P. A. , Kirk A. J. B. , Liles J. H. , Hayes P. H. , Dark J. H.
Published: May 2007

Pain following thoracotomy reduces pulmonary ventilation in man and a similar effect is believed to occur in animals. The effects of two analgesic regimens on arterial blood gas parameters were studied in dogs following thoracotomy. Postoperative analgesia was provided with intermittent nalbuphine, either alone or in combination with an intercostal nerve block using bupivacaine. Arterial blood gas analysis was carried out at 4, 8 and 16h post-operatively, both before the administration of nalbuphine and again 30 min later. Animals which received nalbuphine alone had a significant rise in arterial oxygenation following administration of this analgesic. This effect was not observed at 4 and 8h postoperatively in dogs which had an intercostal block with bupivacaine, but was seen at 16h post-operatively when it could be anticipated that the effects of bupivacaine would have waned. These results suggest that intercostal block with bupivacaine can provide analgesia for over 8h, and that the duration of action of nalbuphine in controlling post-operative pain in the dog is probably less than 4h.
The incidence of Encephalitozoon cuniculi in a commercial barrier-maintained rabbit breeding colony
Authors: Greenstein Gary , Drozdowicz Carla K. , Garcia Felix G. , Lewis Leon L.
Published: May 2007

Between 1982 and 1987 sera from 4952 New Zealand White rabbits ( Oryctolagus cuniculus) obtained from a single commercial supplier were tested for the presence of antibodies to Encephalitozoon cuniculi. A commercially available carbon immunoassay test kit was used. Initially 32·9% of the rabbits were seropositive with the number progressively decreasing to 2·3% by 1987. The reason for the significant decline in the incidence of infection was most likely due to a selection process for breeding stock instituted by the supplier based upon productivity, posture and weight of each animal.
Pathogenicity of Pasteurella multocida A:3 in Flemish Giant and New Zealand White rabbits
Authors: Dillehay D. L. , Paul K. S. , Digiacomo R. F. , Chengappa M. M.
Published: May 2007

Pasteurella multocida A:3 was isolated during an outbreak of pasteurellosis in Flemish Giant (FG) rabbits. Since New Zealand White (NZW) rabbits housed in the same room were not as severely affected as FG rabbits, experimental inoculation was undertaken to determine if FG rabbits were more susceptible than NZW rabbits to pasteurellosis induced by this isolate. Rabbits of each breed were inoculated with P. multocida A:3 and observed for 3 weeks. Four of 5 FG rabbits developed severe clinical disease on days 6, 9, 12 and 14 after inoculation; whereas, the one affected NZW rabbit became ill 14 days after inoculation. All rabbits with clinical disease developed fibrinosuppurative pleuritis, pyothorax and pneumonia which was more severe in FG than NZW rabbits. At necropsy, P. multocida A:3 was isolated from multiple sites of the diseased rabbits. No significant difference ( P=0·099) in the prevalence of lesions between the two breeds was found; however, the score of pneumonia and pleuritis was 3 times greater in FG rabbits than NZW rabbits.
Suppressive effect of nonviable Mycobacterium paratuberculosis on the delayed-type hypersensitivity reaction to sheep erythrocytes in mice
Authors: Kishima M. , Yokomizo Y. , Nonomura I. , Goto N.
Published: May 2007

The effect of nonviable Mycobacterium paratuberculosis on the delayed-type hypersensitivity reaction to sheep erythrocytes (SRBC) in mice was evaluated by means of delayed-type footpad swelling. Intraperitoneal (i.p.) injection with nonviable M. paratuberculosis into mice from 28 days before to 1 day after immunization with SRBC resulted in a significant suppression of footpad swelling to SRBC. The suppressive effect could be transferred by i.p. injection of spleen cells or peritoneal exudate cells from mice which had been pre-treated with nonviable M. paratuberculosis into non-treated recipient mice. The suppressive effect of spleen cells was retained even after passing them through a nylon wool column. The suppressive effect of spleen cells was abolished by treatment with anti-Thy 1·2 monoclonal antibody plus complement or anti-Lyt 2·2monoclonal antibody plus complement. However. treatment of spleen cells with anti-mouse γ globulin antiserum plus complement or anti-Lyt 1·2monoclonal antibody plus complement did not affect the. suppressive effect of spleen cells. Thesuppression of footpad swelling to SRBC induced by pre-treatment with nonviable M. paratuberculosis could be reversed by i.p. administration of cyclophosphamide. Serum antibody response to SRBC in mice was not affected by pre-treatment with nonviable M. paratuberculosis. These findings indicate that T cells appear to be involved in the suppression of delayed-type hypersensitivity reaction to SRBC in mice by pre-treatment with nonviable M. paratuberculosis.
Effects of pentobarbital and ketamine-xylazine anaesthesia on somatosensory, brainstem auditory and peripheral sensorymotor responses in the rat
Authors: Goss-Sampson M. A. , Kriss A.
Published: May 2007

Somatosensory, brainstem auditory evoked and peripheral sensory-motor responses were recorded in rats anaesthetized with either pentobarbital or a ketamine-xylazine combination. This was carried out in order to assess which of these agents degraded responses to a lesser extent and thus would be more suitable for monitoring experimental effects. Neither of the anaesthetic agents affected peripheral sensory or motor conduction, nor were there any interpeak latency changes of the early components of the brainstem auditory response. However, pentobarbital anaesthesia resulted in an increase in latency of the initial positive component of the somatosensory cortical evoked potential and attenuation of the following negative component. During the recovery stages of ketamine-xylazine anaesthesia the longer latency evoked potential components were observed to emerge.
Husbandry, reproduction and postnatal development of the Neotropical muroid rodent Zygodontomys brevicauda
Authors: Voss Robert S. , Heideman Paul D. , Mayer Victoria L. , Donnelly Thomas M.
Published: May 2007

Laboratory colonies of the Neotropical muroid rodent Zygodontomys brevicauda have been employed in studies of arbovirus epidemiology and are currently the subjects of experimental research on tropical mammalian reproductive physiology and evolutionary quantitative genetics. Captive-bred litters typically consist of 4 or 5 pups weighing 3-4 g each at birth. Adults 20-40 weeks old average 60-80 g with some sexual dimorphism. Females are sexually mature at 3-4 weeks of age, males at 6-8 weeks. Ovulation is spontaneous and gestation is 25 days. Preliminary observations are provided on the microbiological status and parasites of captive-bred animals.
An improved method for direct laryngeal intubation in the guineapig
Authors: Turner M. A. , Thomas P. , Sheridan D. J.
Published: May 2007

A novel method of direct laryngeal intubation in the guineapig, using a modified laryngoscope blade, is described. The method has been used in over 400 animals and has proved suitable for recovery procedures and repeated intubation.
A new device for long-term continuous enteral nutrition of rats by elementary diet via gastrostomy, following extensive oesophageal or lower gastrointestinal surgery
Authors: Müller G. , Schaarschmidt K. , Stratmann U.
Published: May 2007

A device for intragastric nutrition of unsedated and minimally restrained rats under complete alimentary abstinence has been developed. The cannulation system consists of an infusion pump, modified glass syringe as flow swivel, rat-harness and a silicone-tube-gastrostomy. The animals were kept in special cages and coprophagy was prevented by an own model of faecal collection cup.

Methionine and Ca-glycerophosphate had to be added to a commercial elementary diet. The rats were allowed to move freely during intragastric infusion, which was applied for 14 to 28 days in 118 Wistar-rats (350-400 g). They maintained weight on an energy supply of 86·4 kcal/day.
Intratracheal aerosolization of endotoxin in the rat: a model of the adult respiratory distress syndrome (ARDS)
Authors: Wheeldon E. B. , Walker M. E. , Murphy D. J. , Turner C. R.
Published: May 2007

A technique is described for the intratracheal aerosolization of endotoxin into the rat. Using a miniaturized nozzle within the tracheal lumen to optimize uniform distribution 0·5 ml of an endotoxin solution (7 mg/kg) was aerosolized and dispersed throughout the lung. Time course studies of pulmonary function and histological changes revealed marked functional and morphological changes by 24 h. Histopathologic changes consisted of widespread pulmonary oedema and a diffuse neutrophilic alveolitis. At the same time, there were significant decreases in tidal volume, minute ventilation and lung compliance. Haematologic changes were also seen, including profound chrombocytopaenia and leukopaenia together with an increased haematocrit, indicating systemic effects in this model. Bronchoalveolar lavage (BAL) at 24 h revealed significant increases in BAL protein, erythrocytes and neutrophils. The functional, cytological and histological changes observed after endotoxin challenge mimic those seen in the Adult Respiratory Distress Syndrome in humans and can thus be used as a model to compare the efficacy of a variety of therapeutic interventions for this syndrome.
Utilization of cholestyramine resin as a preventive treatment for antibiotic (clindamycin) induced enterotoxaemia in the rabbit
Authors: Lipman N. S. , Weischedel A. K. , Connors M. J. , Olsen D. A. , Taylor N. S.
Published: May 2007

Cholestyramine, an ion exchange resin shown to bind bacterial toxins, was utilized to treat rabbits with antibiotic induced enterotoxaemia. Three groups of 6 rabbits were administered 30 mg/kg clindamycin phosphate intravenously on day 1. One group was untreated; 2 groups were treated daily by gavage with 2 g cholestyramine in 20 ml water until day 21, starting on either day 1 or 3. Daily body weights, faecal output, faecal occult blood, food and water consumption, and body temperatures were determined. Four of 6 rabbits in the untreated group either died or were moribund and euthanased. There were no deaths in either treatment groups. Dramatic decreases in food consumption (86%), water consumption (62%), and faecal output (89%) were noted with-in 3 days after clindamycin administration in all groups. These parameters remained depressed throughout the study. There was no clear trend in body weight changes, body temperature, or faecal occult blood test results. Cholestyramine was effective in eliminating mortality associated with the intravenous administration of clindamycin and is recommended to prevent the development of enterotoxaemia when pyrogen testing or administering antibiotics known to induce the syndrome in rabbits.
Histological changes in the orbital region of rats after orbital puncture
Authors: van Herck H. , Baumans V. , van der Craats N. R. , Hesp A. P. M. , Meijer G. W. , van Tintelen G. , Walvoort H. C. , Beynen A. C.
Published: May 2007

To contribute to the assessment of the degree of discomfort in rats after orbital puncture, we have examined the histological changes in the intra-orbital tissues caused by this technique of blood sampling. Orbits were studied from rats euthanized either within 1 min, 4 days, 28 days or 56 days after puncture while under diethyl-ether anaesthesia. The techniques of 2 animal technicians were compared, one using a broken haematocrit capillary and the other using an intact Pasteur's pipette. Non-punctured orbits served as controls. Microscopic slides containing the eye in situ at 2 horizontal levels in the orbital region were examined for 37 parameters; the slides were scored blind and in random order. Orbital puncture caused haemorrhages in the puncture track and, depending on the technique used, also in the periosteum. Four days after puncture, inflammatory reactions were present in the puncture track. Depending on the technique of puncture, these reactions were also seen in the eye muscles and periosteum or in the Harderian gland. Within 4 weeks after puncture, the lesions had healed without detectable scars. The different histological effects of the 2 techniques of orbital puncture are discussed in the light of the characteristics of these techniques.
Electron microscopy of the oxynticopeptic cells of the gastric glands and the intestinal glands of the caecum of the guineapig
Authors: Bal H. S. , Ghoshal N. G.
Published: May 2007

Histomorphology of the gastric and intestinal glands was investigated in 19 sexually mature, adult guineapigs by light and transmission electron microscopy. Gastric glands exhibited the cytological characteristics of oxynticopeptic cells capable of both hydrochloric acid (HCl) and pepsinogen secretion. In the literature, occurrence of oxynticopeptic cells in tbe proventriculus of the domestic fowl (Toner, 1963; Bell & Freeman, 1971) and in the gastric glands of frogs has been reported (Sedar, 1961; Patt & Patt, 1969; Forte & Forte, 1970). It has been claimed by other investigators (Herriot et al., 1938; Long, 1967) that simultaneous secretion of HCl and pepsinogen by a single, not completely differentiated 'pure' cell type, was highly effective for rapid conversion of the zymogen to active enzyme. Under the light microscope with haematoxylin and eosin stain, the protein secreting activity of gastric glands in guineapigs was masked by the HCl secreting activity, thus morphologically resembling the oxyntic cells. Therefore, different cell types, for example protein-secreting peptic cells and the acid-secreting oxyntic cells, could not be distinguished on the basis of their morphology and staining affinity. For histochemical evaluation of the sections with stains-all method, most cells in the gastric glands responded by a positive reaction to protein. Further, protein containing cells were seen in the intestinal glands of the guineapig caecum. The function of this cell type was correlated with caecotrophic food habits of this species.
A case of endometriosis in the macaque diagnosed by nuclear magnetic resonance imaging
Authors: Waterton John C. , Miller Diane , Morrell John S. W. , Dukes Michael , West Christoper D. , Wadsworth Peter F.
Published: May 2007

A case of spontaneous endometriosis was diagnosed in the pigtailed macaque ( Macaca nemestrina nemestrina) with the aid of high-field (2·35 T), T2-weighted (TE50), C1H2-suppressed, oblique nuclear magnetic resonance imaging (MRI). Postmortem histology was obtained. A variety of endometriotic lesions was seen with MRI, including extrauterine hyperintense apparently cystic regions, extrauterine hypointense regions apparently associated with intracellular paramagnetic iron proteins, and an enlarged myometrium exhibiting adenomyosis foci.
Fentanyl and medetomidine anaesthesia in the rat and its reversal using atipamazole and either nalbuphine or butorphanol
Authors: Hu C. , Flecknell P. A. , Liles J. H.
Published: May 2007

The intraperitoneal injection of anaesthetic agents is a simple and convenient method of anaesthetizing rats. However, all of the anaesthetic combinations in current use which are administered by intraperitoneal injection produce prolonged sedation, and full recovery of consciousness may take several hours.

Fentanyl, a μ agonist opioid, and medetomidine, an α2-adrenoceptor agonist were mixed and administered as a single intraperitoneal injection. Combinations of 300 μg/300 μg/kg and 300 μg/200 μg/kg of fentanyl/medetomidine were shown to produce surgical anaesthesia in the rat. This anaesthetic regimen produced significant respiratory depression ( P<0.01) and animals did not regain their righting reflex until 193±21 min (mean±1 SD) after injection. Administration by intraperitoneal injection of atipamezole, a specific α2-adrenoceptor antagonist (1 mg/kg) mixed with a μ antagonist/k agonist opioid (nalbuphine, 2 mg/kg or butorphanol 0·4 mg/kg), resulted in a rapid (<8 min) reversal of anaesthesia and the associated respiratory depression, and apparent full recovery of consciousness.
Enhanced potentials for mammary tumourigenesis and uterine adenomyosis in (SLN ± C3H/He)F1 virgin mice
Authors: Nagasawa H , Naito T.
Published: May 2007

(SLN × C3H/He)F1 virgin female mice showed higher incidences of spontaneous mammary tumours and uterine adenomyosis at advanced age than did the parental strains.