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H Hackbarth

Publications and source records attributed to H Hackbarth.

At least 19 recordsLinked to original sources
PubMed2006

[Recognizing and assessing aggressive behaviour in dogs].

Within the population the sensitivity to aggressive behaviour in dogs has increased. The authorities are confronted with a problem: if any incident occurs it is their task to decide whether the dogs involved constitute a threat to other people or whether the charge is only the result of a quarrel between neighbours. For this reason, an examination of the dogs with regard to their aggressive behaviour is necessary. Seen from the biological point of view, aggressive behaviour is one of four possibilities a dog can chose from to solve a conflict. The dog's intention in showing aggressive behaviour is to eliminate disturbances and to maintain a distance in space and time. Aggressive behaviour might also be necessary to acquire or defend resources essential to the dog's life. This is to secure its survival and its success in reproduction. One can see from this that aggressive behaviour is a very important and biologically necessary adjustment factor. However, when living together with man aggressive behaviour might become a problem. For the assessment and the therapy of the problem it is necessary to exa-mine the behaviour shown by the dog with regard to its cause. To be able to do this an exact anamnesis, a medical check, and an examination of the dog on the basis of its display in special situations are necessary. For this reason, exclusively veterinarians with a special further education in the field of behaviour should carry out the examination of dogs.

Aggression↗
PubMed2003

Are the effects of different enrichment designs on the physiology and behaviour of DBA/2 mice consistent?

Environmental enrichment is intended to improve the well-being of laboratory animals. Although many researchers have indicated that environmental enrichment may enhance animal well-being, there is some evidence that enrichment differs in its effects on physiology and behaviour between species and strains. The present study focuses on the effects of different enrichment designs on the physiology and behaviour of male and female DBA/2 mice. A total of 48 DBA/2J mice, 24 males and 24 females were used for this experiment. Upon arrival at about 3 weeks of age, the animals were randomly allotted to three experimental groups: NE, non-enrichment; E1, enriched with nest box, wooden climbing bar and nest material according to Scharmann (1993); E2, enriched with horizontal and vertical dividers, modified from Haemisch and Gärtner (1994). Same-sex groups of four mice were housed for 12 weeks in type III Makrolon cages with (E1 or E2) or without (NE) enrichment objects. Behavioural performance (Open Field, Food Drive and Elevated Plus Maze tests) and physiological traits (haematological variables, body weight and organ weights, corticosterone and thyroxine levels) were measured. This study observed that enrichment had significant effects on the mean values of body weight (females), Open Field and Food Drive tests. The most significant housing differences were found between the E2 and NE/E1 groups. Furthermore, sex differences in the NE, E1 and E2 groups were not consistent for several variables (growth rate, relative weights of spleen, kidney and heart, Food Drive and Elevated Plus Maze behavioural performance). There was often a higher coefficient of variation (CV) in the E1 and E2 groups as compared to the NE group, chiefly in physiological traits and in the Open Field and Food Drive tests. The results of this study indicate, that the effects of enrichment designs used in the present study are not consistent, but vary according to sex and the variable studied.

Aging↗
PubMed2003

The effects of different rack systems on the breeding performance of DBA/2 mice.

Housing systems for laboratory animals have been developed over a long time. Micro-environmental systems such as positive, individually ventilated caging systems and forced-air-ventilated systems are increasingly used by many researchers to reduce cross contamination between cages. There have been many investigations of the impact of these systems on the health of animals, the light intensity, the relative humidity and temperature of cages, the concentration of ammonia and CO(2), and other factors in the cages. The aim of the present study was to compare the effects of different rack systems and to understand the influence of environmental enrichment on the breeding performance of mice. Sixty DBA/2 breeding pairs were used for this experiment. Animals were kept in three rack systems: a ventilated cabinet, a normal open rack and an individually ventilated cage rack (IVC rack) with enriched or non-enriched type II elongated Makrolon cages. Reproduction performance was recorded from 10 to 40 weeks of age. In all three rack systems there was a similar breeding index (pups/dam/week) in non-enriched groups during the long-term breeding period, but the coefficients of variation in the IVC rack were higher for most parameters. This type of enrichment seems to lead to a decrease in the number of pups born, especially in the IVC group. However, there was no significant difference in breeding index (young weaned/female/week).

Aging↗
PubMed2002

Impact of environmental enrichment in mice. 1: effect of housing conditions on body weight, organ weights and haematology in different strains.

Currently, environmental enrichment is a very common means of improving animal well-being, especially for laboratory animals. Although environmental enrichment seems to be a possible way for improving the well-being of animals, the consideration of housing laboratory animals should not only focus solely on animal well-being, manpower and economics but also on the precision and accuracy of the experimental results. The purpose of the present study was to evaluate the effects of enriched cages (nest box, nesting material, climbing bar) on body weight, haematological data and final organ weights. BALB/c, C57BL/6 and A/J mice, originated from Harlan Winkelmann, were used for the experiments - 16 animals of each strain. Animals at 3 weeks of age were marked and separated randomly to enriched or non-enriched cages, in groups of four, half for each housing condition. Both cages were type III Makrolon cages, only the enriched cages contained a nest box, a wood bar for climbing and nesting material. Animals were kept in a clean animal room under specific pathogen free (SPF) conditions. Body weights were recorded every week. Blood samples were collected at 14 weeks of age (white blood cells (WBC), red blood cells (RBC), haemoglobin (HGB), and haematocrit (HCT) were analysed). At 15 weeks of age, the animals were euthanized by CO(2) in their home cages, and final body weight and organ weights (heart, liver, kidney, adrenal, spleen and uterus) were recorded immediately. Although nearly all the test variables were not affected by environmental enrichment in their mean values, the enriched group showed higher coefficients of variation in many variables, and strain differences of both housing conditions were not consistent. The influences of enrichment were shown to be strain- and test-dependent. Such effects may lead to an increase in the number of animals which is necessary or may change the experimental results, especially when a study, using enriched housing conditions, focuses on strain differences. Since the same enrichment design can result in different influences, a positive or a negative or no adverse effect, due to the strain and the variables studied, researchers need to collect more information before enrichment designs are introduced into experimental plans.

Age Factors↗
PubMed2002

[Possibilities and limits of the inspection of animal experiments and laboratory animal facilities].

Animal experiments according to section 7-9 of the German animal welfare act underlie governmental inspection. Generally this inspection is taken over by the veterinary offices of the cities and districts. During the inspection of animal experiments, which have to be licensed or announced according to section 8 or 8a respectively, the main focus should be the observance of the license presumptions and conditions, the knowledge of the experimenter and the necessity of recordings. For this task specialized knowledge in laboratory animal science of the inspection office is a necessary presupposition for the effectiveness and acceptance of the inspection. As this inspection can only be spot-checking it should be done in a close and collegial cooperation with the animal welfare officer of the experimental institution. The animal welfare officer has the necessary knowledge and knows the institutional conditions, especially the time scheme, which are necessary for an effective inspection of animal experiments. Without the participation and cooperation with the animal welfare officer the inspection office runs the risk not to recognize certain interrelations, but also to give way to wrong descriptions. It is very difficult especially during the inspection of institutions, where many research groups perform animal experiments to get and to keep an overview, without not noticing important details or focussing on certain details, while others are taken no notice of. The primary goal of the inspection of animal experiments should be: 1. to understand the research goal and the methods used 2. to ask with scientific background for the purpose of research and the experimental design 3. to judge the applied experimental methods in respect to animal welfare aspects 4. to improve the animal experimentation by discussion with the experimenter Does the inspection office succeed to be accepted as a competent partner by the experimenter as well as by the animal welfare officer, the inspection of animal experiments itself as well as the achievement of refinement for practical animal welfare is more easy and more effective than a simple bureaucratic control.

Animal Husbandry↗
PubMed2000

Euthanasia of rats with carbon dioxide--animal welfare aspects.

A method of inducing euthanasia by carbon dioxide (CO2) inhalation in the home cage of an animal is described and tested for distress by behavioural as well as by hormonal measures. The animals were maintained in their home cage while CO2 was induced at a flow of 6 l/min. The behaviour of the animals was measured continuously as were the serum concentrations of glucose, ACTH and corticosterone 30, 75 and 120 s after the CO2 was introduced into the cage. In order to test for distress, two groups of rats were pre-treated with acepromazine (orally) and pentobarbiturate (i.p. injection) respectively, in order to reduce possible distress caused by CO2 euthanasia, and were compared with control groups. There were no signs of distress by behavioural or by hormonal changes. All changes seen could be attributed to experimental effects and, especially as there was no difference between the pre-treated and the control groups of rats, it must be assumed that the described method of euthanasia is in concordance with animal welfare, it leads to rapid death without severe distress or pain, and it seems therefore to be 'humane'.

Acepromazine↗
PubMed1999

Allometric comparison of recommendations of minimum floor areas for laboratory animals.

The recommendations for minimum floor area given in the European Convention for the Protection of Vertebrate Animals used for Experimental and other Scientific Purposes (1986), as well as in the Publication on the Planning and Structure of Animal Facilities for Institutes Performing Animal Experiments of the Society for Laboratory Animal Science (GV-SOLAS 1989), are plotted in a double logarithmic system in order to get an allometric function of recommended floor area to body weight. Both recommendations correspond very well with the so-called metabolic body weight seen at the allometric exponent of 0.73 and 0.70 respectively. Thus the recommendations in general attribute the floor space according to the metabolic body weight of the animal. Nevertheless, despite this general rule, some species are recommended less space than others when measured on this allometric scale. Thus it must be questioned why, for example, rabbits, chicken and pigs are recommended less space than other species. The general allometric measure seems at least to be a good scale for the comparison of recommended floor space, and for the discussion of species-specific needs for more or less space.

Animal Husbandry↗
PubMed1997

[The Animal Welfare Center of the Veterinary School of Hanover].

Animal welfare is initiated from different motivations with very different targets. The main areas are the emotional, the legal and the scientific animal welfare. The intention of a scientifically based animal welfare is discussed. The new founded animal welfare center of the veterinary school in Hannover initiates, coordinates and promotes research in the direction of a scientific animal welfare from the understanding and conviction that only knowledge protects animals.

Animal Welfare↗
PubMed1995

A study on the prevention of prenatal and galactogenic Toxocara canis infections in pups by treatment of infected bitches with ivermectin or doramectin.

Investigations were carried out to test the efficacy of a two dose treatment with ivermectin or doramectin on reactivated larvae of Toxocara canis in bitches to prevent prenatal and galactogenic infections of their pups. Thirty pregnant bitches were treated by subcutaneous injection of ivermectin or doramectin on day 40 and 50 post conception (p.c.) each with a dose of 1 mg/kg body weight. The efficacy of the treatments was determined by faecal examinations and by comparing the number of infected pups and the onset of patency in each group of pups. 1. Patient infections with T. canis were seen in pups from untreated bitches from day 21 after birth and all pups were coproscopically positive one week later. To prevent severe clinical symptoms all pups in this group were treated with anthelmintics on day 42 after birth. 2. Pups from ivermectin treated bitches occasionally exhibited patent infections from day 28 after birth onwards; pups from doramectin group exhibited infections from day 56 after birth. The number of patently infected pups in both groups increased till 70 days after birth, probably because of postnatal infections. 3. 28 days after parturition, T. canis infections became patent in all untreated bitches. Single bitches in the ivermectin and doramectin groups developed patent infections after day 49 after parturition. All coproscopically positive bitches had patently infected pups in their litters. 4. The contamination of the environment with eggs of T. canis was calculated from the results of the faecal examinations.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

[Morphometric studies of the proximal tubules of the rat kidney considering the effect of the method of killing].

120 male rats belonging to two different strains (Han: WIST, Han: SPRD) and two different weight groups (group I: lighter body weight, group II heavier body weight) were killed on three different methods (decapitation, Nembutal -overdose greater than 250 mg/kg b.w. i.p. less than, exsanguination in Nembutal -anaesthesia greater than 100 mg/kg b.w. i.p.). Subsequently, changes in tubuli contorti I of the left kidneys were examined morphometrically. The mean total area, luminal area and epithelial area were evaluated as well as the mean diameter of the tubular nuclei. Concerning the areas of the proximal tubules only the luminal areas show differences between the Wistar and the Sprague-Dawley strain. The total, luminal and epithelial area in the rats belonging to the weight group II were significantly larger than in the rats belonging to weight group I. With one exception this could be noticed within both strains and all three modes of killing. In both strains and weight groups the rats were killed by Nembutal -overdose or exsanguination showed significantly smaller total, luminal and epithelial areas than the rats that were decapitated. Possible cause heretofore are discussed. Differences between the tubular areas of the rats that were killed by Nembutal -overdose and those that were killed by exsanguination after Nembutal -anaesthesia could not be established. The measurements of nuclei diameters in the proximal tubules did not lead to clearly different results between both strains, weight groups and the various modes of killing.

Animals↗
PubMed1989

[Animal welfare relevance and the functional and morphological significance of the killing of laboratory animals].

Euthanasia of experimental animals at the end of an experiment or when an experiment is terminated is relevant for two reasons: firstly, because of ethical reasons and of animal protection, secondly because of scientific evaluation of experimental results. Functional and morphologic alterations have up to now been inadequately observed and considered. Gradually varying different results depend on the different methods of euthanasia. Additionally single parameters of reactions in isolated organs vary depending on the method of euthanasia. These facts have not yet been respected in the discussion of so called alternate methods. The significance of functional and morphologic effects as seen in different methods of euthanasia is discussed with examples.

Animal Welfare↗