A comparative histochemical study of some oxidative and hydrolytic enzymes in the kidneys of domestic food animals, laboratory animals and the fowl.
Explore the source record for details and available documents.
SEARCH · Search PubMed
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Laboratory animal (LA) workers are frequently affected with allergic sensitization and occupational asthma (OA). The role of preexposure host factors, in particular airway responsiveness, on the incidence of OA has not been satisfactorily studied. A prospective cohort study of 417 apprentices in animal-health technology was conducted to investigate the incidence and determinants of probable OA. Questionnaire and skin-prick tests with common and work-specific allergens were administered on entry and at follow-up visits (up to three) from 8 to 44 mo after starting apprenticeship. Responsiveness to inhaled methacholine was assessed at baseline and at follow-up in apprentices who developed a new specific skin sensitization and in control subjects. Preexposure host characteristics and the school attended were compared between cases and all cohort subjects not meeting the criteria for probable OA. Twenty-eight apprentices satisfied the definition for probable OA, i.e., onset of immediate skin reactivity to > 1 occupational inhalant and > 3.2-fold decrease in the provocative concentration causing a 20% reduction in FEV(1) (PC(20)). The incidence of probable OA was 2.7% (28/1,043 person-years). Baseline immediate skin reactivity to pets (rate ratio [RR] 4.1, 95% confidence interval [CI] = 1.6 to 10.8), and bronchial responsiveness (PC(20) < or = 32 versus PC(20) > 32 mg/ ml) (RR = 2.5, 95% CI = 1.0 to 5.8) were associated with an increased risk of probable OA; a lower FEV(1) had an apparent, protective effect (RR = 0.58, 95% CI = 0.43 to 0.78). It is concluded that apprentices in animal health show a high incidence of probable OA, and that preexposure airway caliber and responsiveness as well as sensitization to pets are associated with an increased risk.
The prevalence of allergy to laboratory animals (LAA) was investigated in laboratory technicians and animal keepers. In a questionnaire 41 of 101 technicians reported symptoms provoked by work with laboratory animals. On clinical investigation 30 were found to have symptoms and signs related to contact with animals, and allergy was confirmed by radioallergosorbent tests (RAST) and skin tests in 19. All had rhinitis and 10 also had bronchial asthma. Forty seven other technicians who had stopped working with laboratory animals showed the same relative numbers of respiratory tract symptoms and of confirmed allergy to laboratory animals as did those currently handling animals. Seven of 23 animal keepers had work related symptoms. LAA symptoms were found in four and confirmed animal allergy in two. All four animal keepers with animal related symptoms had rhinitis, none had bronchial asthma. Positive animal RAST and skin tests were found only among people with animal related symptoms. A history of atopic disease was commoner among those with positive animal test results than among those with negative test results. No relation between smoking and the development of allergy to laboratory animals emerged. Simple prophylactic measures often sufficed to help technicians with animal related symptoms to remain at work.
The Swiss Federal Act on Animal Protection (1978) requires the sale of mass-produced housing systems for farm animals to be authorized by the Federal Veterinary Office. Authorization is only granted for housing systems that safeguard the animals' welfare. A concept for the assessment of Animal Welfare has to provide a high forensic value. The capacity of farm animals to adapt to an intensive housing system can be directly examined, whereas the existence and extent of subjective feelings can only be assumed. In our concept the examination focuses on the interaction of individuals with their artificial environment. The main question is whether or not the individuals are able to cope with given nonspecific (e.g. temperature, humidity) and specific (e.g. drinking troughs, behaviour of conspecifics) stimuli in order to reach the immediate (e.g. drinking, make way for) and ultimate (survival, reproduction success) goals. Animals of the same breed are observed in a highly diverse environment in order to determine normal behaviour. Whether behavioural expressions which differ significantly from normal behaviour are adaptive to the restrictive housing conditions is judged by the behaviours' consequences for both, the individuals and the environment. Many studies prove the concept's high forensic value and the authorities prefer conclusions based on this concept to others referring to the animals' motivational and emotional state. However more research has to be done with respect to animal welfare in farm and laboratory animal breeding as well as in the use of laboratory animals for experimental studies.
Laboratory animals were exposed by inhalation for 2 hr/day (acute) or 6 hr/day (four consecutive days, repeated dose) to methyl isocyanate (MIC). Exposures were conducted in stainless steel and glass inhalation exposure chambers placed in stainless steel, wire mesh cages. MIC was delivered with nitrogen via stainless steel and Teflon supply lines. Chamber concentrations ranged from 0 to 60 ppm and were monitored continuously with infrared spectrophotometers to 1 ppm and at 2-hr intervals to 20 ppb with a high performance liquid chromatograph equipped with a fluorescence detector. Other operational parameters monitored on a continuous basis included chamber temperature (20-27 degrees C), relative humidity (31-64%), static (transmural) pressure (-0.3 in.), and flow (300-500 L/min). The computer-assistance system interfaced with the inhalation exposure laboratory is described in detail, including the analytical instrumentation calibration system used throughout this investigation.
The use of animals in experimental research parallels the development of medicine, which had its roots in ancient Greece. The increasing demand for high-standard animal models, together with a critical view of the way animals are used, has led to the development of a multidisciplinary branch of science we now know as 'laboratory animal science'. The guiding principles are replacement, reduction and refinement (the Three Rs), first proposed by Russell and Burch in 1959. When animals are used, the people involved have an obligation to safeguard their welfare and minimise discomfort; this will also generally be beneficial for both the animal and the experimental outcome. The ability of an animal to cope with the environment and exert control over its life seems to be crucial for animal welfare. In this paper, attention is paid to the assessment of welfare, environmental factors affecting welfare, legislative requirements and future trends such as the production and use of genetically modified animals.
Explore the source record for details and available documents.
Laboratory matings were attempted to establish breeding colonies of Northern grasshopper mice, Onychomys leucogaster (which were captured in New Mexico, U.S.A.), as experimental animals. The results were as follows. The rate of pregnancy was 75% with cohabitation for more than 30 days, and 4% with cohabitation from 1 to 7 days. Both cases were of monogamous mating. The mean litter size was 3.5 +/- 1.2, with a range of 1 to 6. The rate of weaning was 78.8%. The mean gestation period was 27.4 +/- 2.0 days, with a range of 25 to 31. The gestation period was achieved by the method of confirming sperm from smears. Further, it was possible to breed all year round in a rearing room with fixed temperature and humidity.
Laboratory animal technology has evolved into a specialised field of expertise which is associated with the production, care and use of laboratory animals in biomedical teaching and research. A survey of laboratory animal facilities and supporting personnel was undertaken to assess the uses of laboratory animals in relation to the administrative and technical staffing of animal facilities. The results of this study indicate that there is a need for training in laboratory animal science at both the technical and professional levels. Options for the development of formal training in laboratory animal technology are reviewed.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Laboratory animal allergy (LAA) is a form of occupational allergic disease. The development of laboratory animal allergy is due to the presence of IgE antibodies directed against animal proteins. The process of sensitization (development of IgE antibodies) is a complex process which involves interaction of antigen presenting cells and lymphocytes of the Th-2 cell type. These cells generate a host of cytokines and other factors which lead to immediate hypersensitivity reactions and other factors which lead to immediate hypersensitivity reactions and the generation of allergic inflammation. Typical symptoms of laboratory animal allergy include nasal symptoms, such as sneezing, watery discharge, and congestion. Skin rashes are also common. Asthma, which produces symptoms of cough, wheezing, and shortness of breath, may affect 20-38% of workers who are sensitized to laboratory animal allergens. Rarely a generalized, life-threatening allergic reaction (anaphylaxis) may occur. The estimated prevalence of laboratory animal allergy is variable depending on the method used for diagnosis, but nonetheless may affect up to 46% of exposed workers. The presence of pre-existing allergies to non-work place allergens (e.g., dust mite, pollens, molds), exposure to laboratory animal allergens, and possibly tobacco smoking are risk factors for the development of laboratory animal allergy. Progress in the understanding of the mechanism and epidemiology of laboratory animal allergy will lead to improved methods for its prevention.
Explore the source record for details and available documents.
BACKGROUND: Family members of laboratory animal workers are at risk of developing allergy to laboratory animals. Little is known about the spreading of laboratory animal allergens outside the animal facilities. OBJECTIVE: To assess the presence of laboratory animal allergens in dust collected from mattresses of laboratory animal workers and unexposed controls. METHODS: Mouse and rat urinary proteins were measured in samples of mattress dust collected by laboratory animal workers and unexposed controls. In addition, rat and mouse allergens were determined in extracts of hair-covering caps, used during laboratory animal work, to estimate spreading of allergen through dust captured on hair. Allergen concentrations on hair caps were compared with exposure measured by personal airborne dust sampling. RESULTS: Levels of rat urinary allergens (RUA) and mouse urinary allergens (MUA) and mouse urinary protein (MUP) 8, a specific pheromone-binding mouse allergen, were significantly higher in mattress samples of laboratory animal workers than in those of controls. Hair-covering caps used in animal facilities harboured large amounts of RUA and MUA, which correlated significantly with exposure measured by the personal sampling technique in the animal facility. CONCLUSIONS: Occupational laboratory animal allergens are detectable in mattress dust of laboratory animal workers. Transfer of allergens via uncovered hair of animal workers is likely contributing to this phenomenon. This study stresses the importance of using hair caps to prevent spreading of occupational allergens.