Polypropylene Cages Research Articles

Digestibility of plant protein-based diets by largemouth bassMicropterus salmoides

Commercial farming of carnivorous fish demands the reduction of environmental impact of feeds; that requires minimal use of dietary animal protein. This study investigated the digestibility of diets formulated exclusively out of plant protein, added feed attractants, by the carnivore largemouth bass, Micropterus salmoides. Juvenile largemouth bass (14.0 ± 1.0 cm) conditioned to accept artificial, dry feed were confined in polypropylene cages and fed ad libitum in three daily meals, seven experimental diets containing varying levels of vegetable and animal protein sources, added of different feed stimulants. After last daily meal, cages were transferred to cylindrical–conical-bottomed, 200-L aquaria, where faeces were collected by sedimentation into refrigerated containers, preserved and later analysed for chemical composition. Soybean meal can be used as partial substitute of animal protein in diets for largemouth bass; the poultry by-product meal shows as a good option as animal protein source in these rations. Control treatment – 50PP : 50AP – yielded best performances; the need for the use of fish meal in the formulation for carnivorous diets is, at least, questionable. Results of the digestibility trials demonstrated the importance of determining the diet digestibility, if precision in the formulation of least-cost feeds for carnivorous fish is the ultimate goal.

A Model of Neural Cross-Talk and Irritation in the Pelvis: Implications for the Overlap of Chronic Pelvic Pain Disorders

Irritable bowel syndrome, interstitial cystitis, and other chronic pelvic pain (CPP) disorders often occur concomitantly. Neural cross-talk may play a role in the overlap of CPP disorders via the convergence of pelvic afferents. We investigated the hypothesis that afferent irritation of one pelvic organ may adversely influence and sensitize another via neural interactions. We measured pelvic organ smooth muscle and striated muscle reflexes during micturition and colorectal distention (CRD) in urethane-anesthetized rats. The effects of acute cystitis on distal colonic sensory thresholds to CRD and the effects of acute colonic irritation on micturition parameters were assessed. External urethral sphincter (EUS) electromyography (EMG) was typical for the rat, with phasic firing during micturition. External anal sphincter EMG also showed phasic firing during micturition in synchrony with EUS activity but, in addition, showed both tonic bursts and phasic firing independent of EUS activity. Before bladder irritation, graded CRDs to 40 cm H2O produced no notable changes in abdominal wall EMG activity. Following acute bladder irritation, dramatic increases in abdominal wall EMG activity in response to CRD were observed at much lower distention pressures, indicating colonic afferent sensitization. Analogously, following acute colonic irritation, bladder contraction frequency increased 66%, suggesting sensitization of lower urinary tract afferents. We report compelling evidence of bidirectional cross-sensitization of the colon and lower urinary tract in a novel experimental model. This cross-sensitization may account for the substantial overlap of CPP disorders; however, further studies are needed to fully characterize these pathways.

PREVENTIVE EFFECTS OF GARLIC EXTRACT ON LIPID PEROXIDATION AND ANTIOXIDANT DEFENCE SYSTEM IN N-NITROSODIETHYLAMINE INDUCED HEPATOCARCINOGENESIS IN RATS

ISHS III WOCMAP Congress on Medicinal and Aromatic Plants - Volume 6: Traditional Medicine and Nutraceuticals PREVENTIVE EFFECTS OF GARLIC EXTRACT ON LIPID PEROXIDATION AND ANTIOXIDANT DEFENCE SYSTEM IN N-NITROSODIETHYLAMINE INDUCED HEPATOCARCINOGENESIS IN RATS

ANTIULCER PROPERTIES OF ALCOHOLIC EXTRACT OF CYNODON DACTYLON IN RATS

ANTIULCER PROPERTIES OF ALCOHOLIC EXTRACT OF CYNODON DACTYLON IN RATS

Bisphenol A is released from used polycarbonate animal cages into water at room temperature.

Bisphenol A (BPA) is a monomer with estrogenic activity that is used in the production of food packaging, dental sealants, polycarbonate plastic, and many other products. The monomer has previously been reported to hydrolyze and leach from these products under high heat and alkaline conditions, and the amount of leaching increases as a function of use. We examined whether new and used polycarbonate animal cages passively release bioactive levels of BPA into water at room temperature and neutral pH. Purified water was incubated at room temperature in new polycarbonate and polysulfone cages and used (discolored) polycarbonate cages, as well as control (glass and used polypropylene) containers. The resulting water samples were characterized with gas chromatography/mass spectrometry (GC/MS) and tested for estrogenic activity using an MCF-7 human breast cancer cell proliferation assay. Significant estrogenic activity, identifiable as BPA by GC/MS (up to 310 micro g/L), was released from used polycarbonate animal cages. Detectable levels of BPA were released from new polycarbonate cages (up to 0.3 micro g/L) as well as new polysulfone cages (1.5 micro g/L), whereas no BPA was detected in water incubated in glass and used polypropylene cages. Finally, BPA exposure as a result of being housed in used polycarbonate cages produced a 16% increase in uterine weight in prepubertal female mice relative to females housed in used polypropylene cages, although the difference was not statistically significant. Our findings suggest that laboratory animals maintained in polycarbonate and polysulfone cages are exposed to BPA via leaching, with exposure reaching the highest levels in old cages.

Strain-Specific Effects of Cage Enrichment in Male Laboratory Mice(Mus Musculus)

Abstract‘Environmental enrichment’ is often considered to improve captive animal welfare. However, some studies using male mice,Mus musculus, indicate that increasing cage complexity increases aggression. Limited evidence suggests that enrichment differs in its effects on behaviour and physiology between strains; but behaviour also differs between strains in non-enriched environments. Differences in enrichment type, evaluation methods, and strains used, have caused difficulty in interpreting the efficacy of environmental enrichment in improving welfare. Using enrichment suitable for commercial laboratories (nesting material and a Perspex tunnel), we compared within-cage behavioural and physiological responses among males of six strains housed in non-enriched standard polypropylene cages with those housed in ‘enriched’ cages. Outbred ICR(CD-l) and TO mice, and inbred BALB/c mice were more aggressive than C57BL/6, CBA/Ca and DBA/2 mice, which exhibited low levels of aggression typical of most inbred strains. Enrichment did not significantly affect aggression levels. Animals in enriched cages spent more time investigating the internal cage environment, eating and drinking, and in stereotypic behaviour patterns, although levels differed between strains. The greatest increase in stereotypy levels (bar-related stereotypies) with enrichment was found in DBA/2 mice. Higher testosterone levels were maintained over the study period in mice housed in enriched cages, and in more aggressive strains. IgG levels were also higher in mice housed in enriched cages, and in the outbred strains ICR(CD-l) and TO compared with inbred strains. The relationship between aggression, testosterone and ‘enrichment ‘ suggests that increasing complexity in laboratory cages may increase a naturally selected territorial response in some strains. The implications for strain-specific welfare are discussed.

Comparative study of the action of flunixin meglumine and tolfenamic acid on prostaglandin E2synthesis in bovine inflammatory exudate

An acute non-immune inflammation model was used to compare the action of two non-steroidal anti-inflammatory drugs, flunixin meglumine and tolfenamic acid, on prostaglandin E2 (PGE2) synthesis in bovine inflammatory exudate. The tissue cage model used involves subcutaneous implantation of polypropylene cages and subsequent stimulation by carrageenan injection of the granulation tissue which develops within the cage. Twelve calves were randomly assigned to three groups receiving placebo, flunixin meglumine and tolfenamic acid, respectively. Inflammatory exudate was sampled 30 min after carrageenan injection and at seven subsequent time points. PGE2 levels were determined by radioimmunoassay. At each time point post-carrageenan injection, flunixin meglumine inhibited PGE2 synthesis to a greater extent than tolfenamic acid. At 4, 8, 12 and 24 h these differences were statistically significant.

Rat brain acetylcholinesterase response to monocrotophos and abate.

All the reagents used in the present study were obtained from SIGMA and used without further purification. Technical grade of MCP (purity > 95%) was a gift from NOCIL, Bombay and abate (purity > 95.5%) from VOLHRO, Hyderabad. Male Wistar strain rats weighing about 120 + 5 gms used in the present experiment were obtained from Centre for Cellular & Molecular Biology, Hyderabad. They were housed in polypropylene cages (shoe box cage with stainless steel grill tops 29x22x13.5 cms.) maintained at 22 + 2 ~ C with 55+10% relative humidity at 12 hours dark and 12 hours light cycles. The animals had free access to food (supplied by Lipton India Ltd., Bangalore) and sterile drinking water. The rats were divided into two groups and orally administered LD50 doses of 20 mg/kg MCP and 8,600 mg/kg abate respectively. Send reprint request to J V Rao at the above address

Energetics and Weight Changes of Northern Bobwhites Fed 6 Different Foods

Northern bobwhites (Colinus virginianus) fed 6 individual foods were able to metabolize a greater portion of the energy in common sorghum, Maximilian sunflower (Helianthus maximilianii), and a prepared mash than in ox-eye heliopsis (Heliopsis helianthoides), common soybean, and smooth sumac (Rhus glabra). Bobwhites gained weight when provided sorghum or the prepared mash but lost weight when fed sunflower, soybean, heliopsis, and sumac. J. WILDL. MANAGE. 50(2):236-238 Bobwhite populations are limited by various environmental factors, primarily food and cover (Rosene 1969). Habitat enhancement programs of most state agencies and private interests concentrate on these 2 habitat parameters in their attempt to increase quail populations. Dietary stress in northern portions of the bobwhite's winter range often results in weight loss and reduced fat reserves (Robel 1972, Robel et al. 1974), both of which reflect constrained metabolizable energy intake. Kendeigh and West (1965) have documented the gross energy content of many important foods of granivores. Robel et al. (1979a) have reported the metabolizable energy content of important foods of bobwhites. Robel et al. (1979b) conducted comparative energetic studies of bobwhites on 6 foods. This paper reports energetic responses and weight changes of bobwhites fed 5 foods (seeds) and a commercially pelletized mash prepared by the Kansas State University Department of Grain Science and Industry. The study was supported by the Kans. Agric. Exp. Stn. and the Natl. Skeet Shooting Assoc. Charities Found., Inc. This paper is Contribution 85-202-J, Div. Biol., Kans. Agric. Exp. Stn., Kansas State Univ., Manhattan. MATERIALS AND METHODS Twenty-five adult male bobwhites were confined individually in 48 x 25 x 13-cm polypropylene cages with 1.3-cm hardward cloth tops and removable floors (Case and Robel 1974). The caged birds were housed in an environmental chamber at 9L-15D photoperiod and 5 C temperature to simulate Kansas winter conditions. A balanced maintenance diet, P-18, and water were provided ad libitum prior to and between feeding trials, which were conducted during late summer 1980. This diet contained 20.5% protein, 2.7% fat, and 3.6% crude fiber; the major ingredients by weight were ground sorghum (46%) and ground corn (15%). Bird were weighed daily to 0.1 g during the last 2 hours of the dark period to ensure minimal weight variation (West 1960). After bird weights stabilized (varied <2% [t] of the : wt over the preceding 15 days), the birds were ranked from light to heavy and then separated into 5 equal-sized blocks, after which 5-bird, weight-stratified experimental groups were formed by randomly selecting 1 bird from each of the weight blocks. Birds were weight stabilized and rerandomized into 5-bird, weightst fi d blocks between feeding trials. Birds that d ed during feeding trials were replaced ith randomly selected weight-stabilized birds from the weight-stratified blocks. Weights of experimental birds ranged from 136 to 155 g and averaged 143 g. These weight-stable birds were provided seeds of sorghum, sunflower, sumac, heliopsis, and soybean and the balanced pelletized ration (P-18) during 2 consecutive 3-day feeding trials. Body weight and food intake were monitored daily during the feeding trials; spilled feed and excreta were collected at the end of each 3-day period. Because data from the 1st of 2 consecutive 3-day feeding trials vary widely (Clement 1970), only data collected during each of the 2nd 3-day feeding periods were analyzed. Methodology followed Case and Robel (1974) d is detailed in Middendorf (1981). Energy content of oven dried feed and excreta was determined in a Parr Series 1200 adiabatic calorimeter using a Parr 1101 oxygen b mb under 30 atmospheres of pressure. Three

Carcinogenic potential of hydrotreated petroleum aromatic extracts.

Five experimental petroleum extracts were produced from luboil distillates derived from Middle East paraffinic crude by solvent extraction and severe hydrotreatment. The polycyclic aromatic content (PCA) of the extracts was determined by dimethyl sulphoxide extraction and ranged from 3.7-9.2% w/w. The five extracts were evaluated for their potential to induce cutaneous and systemic neoplasia in female mice derived from Carworth Farm No 1 strain (CF1). The test substances were applied undiluted (0.2 ml per application) to the shorn dorsal skin twice weekly for up to 78 weeks, with 48 mice in each treatment group and 96 in the untreated control group; two further groups, each of 48 mice, were similarly treated either with a non-hydrotreated commercial aromatic extract (PCA content, 19.7% w/v) or with a low dose of benzo(a)pyrene (12.5 micrograms/ml acetone). The mice were housed individually in polypropylene cages in specified pathogen free conditions. The incidence of cutaneous and systemic tumours was determined from histological analysis of haematoxylin and eosin stained tissue sections. The results were correlated with the PCA content of the extracts and compared with those from female mice exposed to a non-hydrotreated commercial aromatic extract. Four of the hydrotreated extracts were carcinogenic for murine skin; the two products with the lower PCA contents were less carcinogenic than the products with the higher PCA contents and all were less carcinogenic than the commercial extract. One extract with the lowest PCA content was non-carcinogenic. Thus refining by severe hydrotreatment was an effective method of reducing the carcinogenic potential of petroleum aromatic extracts. Although other physicochemical properties may influence the biological activity of oil products, the PCA content determined by dimethyl sulphoxide extraction may be a useful indicator of the potential of oil products to induce cutaneous tumours in experimental animals. There was no evidence that the commercial or hydrotreated extracts increased the incidence of systemic neoplasms when applied twice weekly to the dorsal skin.

Effects of prenatal ethanol exposure on iron utilization in the rat

The effects of prenatal ethanol exposure on iron metabolism in rat dams and pups were studied. Sperm-positive nulliparous dams were assigned to groups on the third day of gestation (G3): ET rats were fed a liquid diet containing 9% ethanol (v/v); PC rats were pair-fed a non-ethanol, isocaloric liquid diet; FC rats were fed the same nonethanol diet ad libitum. All animals were individually housed in stainless steel metabolic cages from G3 to G18 and transferred to polypropylene cages to await delivery. Food intake and dam body weight were significantly less in the ET and PC groups compared to the FC control group. Water intake was significantly greater in the ET dams than in controls. Gestation length was significantly increased in the ET rats only. Pup body weight was significantly decreased in the ET rats only compared to controls. Apparent absorption of iron in the ET dams was significantly greater than in the PC and FC dams. The in utero ethanol exposure resulted in a significant increase in liver and femur iron concentrations in the newborn pups when compared to the PC and FC control pups. The marked increase clue to understanding presence of liver pathology that has been reported to occur in children with fetal alcohol syndrome.

Letters to the Editor

Abstract Dear Sir: We wish to alert our colleagues to a possible hazard in using phenol containing disinfecting agents in laboratory animal facilities. For several years, we have used CBA male mice and routinely perform Mishell-Dutton-type cultures of mouse spleen cells immunized with sheep erythrocytes (SRBC). Our normal anti-SRBC response is around 300 to 500 PFC with a background of around 30 to 40 PFC/106 recovered cells. In November 1975, we inadvertently started using O-Syl (National Laboratories, Lehn &amp; Fink Industrial Products Division of Sterling Drug, Inc., Montvale, N. J. 07645) to disinfect the polypropylene cages in which mice are housed (10 to 15/cage). Cages were disinfected weekly by a mixture of hot water and O-Syl (approximately 10 ml in 10 liters of hot water) and rinsed repeatedly with warm water. By February 1976, the anti-SRBC response in spleen cultures declined to around 60 PFC/106 recovered cells. Shortly thereafter the mice developed a dermatitis.