Genetic behavioral aspects of agricultural animals

This paper reviews some experimental methods used in the study of genetic fixed behaviour, some examples of investigations in farm animals as well as some results of the author's studies on the emotionality in pigs are given. Many investigations have been made on the estimation of heritability of behaviour patterns in cattle, pigs, poultry and dogs. Behaviour patterns such as temperament, aggressiveness, and nervousness showed relatively high h2-values; other behaviours like trainability, emotionality, and pre-laying showed relatively low values. Selection experiments were carried out in poultry and dogs. The results showed that after a few generations remarkable differences in behaviour patterns between the new lines and the original populations were obvious. Besides the selected traits, modifications occurred in other behaviour patterns and in physiological responses. The emotionality in pigs was investigated with the open field test in 3 genetic groups: German Landrace (DL), Duroc (DU), and cross-breeding between these breeds (DU x DL). Increasing emotionality was displayed by increasing ambulatory activity and vocalization. The lowest activity was observed in the pure breeds, DU showed less signs of emotionality than DL, whereas DU x DL showed the highest of emotionality.     

The behavior and the husbandry conditions of small laboratory animals--possibilities and limits of the evaluation of the appropriateness and fairness of the treatment of animals

Ethological studies are important means to evaluate the behaviour of small laboratory animals (mouse, rat, guinea-pig and rabbit) and their housing conditions. At any rate, the only sparse range of body expressions, the smallness and preference of night activity of these animals and the erratic occurrence of essential behaviour patterns make the investigations more difficult. On the other hand, the standardization of laboratory housing and the genetic definition of these animals turn out to be favourable. By this way, behaviour-environment-relationships are suitable for evaluation. Taking into consideration methodical and biological restrictions, the specific activities such as fight, relaxed resting behaviour and play as well as unbalanced behaviour patterns and stereotypes can be taken as means of evaluation. Particularly in mice and rabbits, upright position and space consuming activities will be possibly restricted by cage sizes.     

Critical Evaluation of Whole-Body Cryostimulation Protocol in Race Horses

Cold therapy is commonly used to relieve pain and inflammation and to aid in muscle recovery after exercise in human medicine. A number of applications have also been observed in veterinary practice. In this article, a critical evaluation of equine protocol applied with a new commercial concept of equine whole-body cryostimulation (WBC) was made. With this new concept of WBC, the protocol usually utilized for relieving pain and discomfort in humans has been extended to horses. The investigations described herein focus on the reduction of horse skin temperature when applying human WBC protocols. Based on infrared thermography measurements, results show that exposing a horse for 3 minutes to a temperature of −140°C, which are conventional parameters used for humans, does not induce sufficient skin thermal gradients in horses. Consequently, beneficial cold reflexes such as vasomotor, neuroconduction, and biochemical reactions cannot be triggered. Further investigations should therefore be carried out to design an adequate protocol specifically aimed at horses.     

Foraging enrichment for stabled horses: effects on behaviour and selection

The restricted access to pasture experienced by many competition horses has been linked to the exhibition of stereotypic and redirected behaviour patterns. It has been suggested that racehorses provided with more than one source of forage are less likely to perform these patterns; however, the reasons for this are currently unclear. To investigate this in 4 replicated trials, up to 12 horses were introduced into each of 2 identical stables containing a single forage, or 6 forages for 5 min. To detect novelty effects, in the first and third trials the single forage was hay. In the second and fourth, it was the preferred forage from the preceding trial. Trials were videotaped and 12 mutually exclusive behaviour patterns compared. When hay was presented as the single forage (Trials 1 and 3), all recorded behaviour patterns were significantly different between stables; e.g. during Trial 3 in the 'Single' stable, horses looked over the stable door more frequently (P<0.001), moved for longer (P<0.001), foraged on straw bedding longer (P<0.001), and exhibited behaviour indicative of motivation to search for alternative resources (P<0.001) more frequently. When a previously preferred forage was presented as the single forage (Trials 2 and 4) behaviour was also significantly different between stables, e.g in Trial 4 horses looked out over the stable door more frequently (P<0.005) and foraged for longer in their straw bedding (P<0.005). Further study is required to determine whether these effects persist over longer periods. However, these trials indicate that enrichment of the stable environment through provision of multiple forages may have welfare benefits for horses, in reducing straw consumption and facilitating the expression of highly motivated foraging behaviour.     

Experimental reactivation of equine herpesvirus‐3 following corticosteroid treatment

State of latency, well known for several herpesviruses, has been proposed for equine herpesvirus‐3 (EHV‐3) and supported by epidemiological observations. No detailed assessment about reactivation, patterns of excretion and re‐excretion has been formally reported. An experimental reactivation study by corticosteroid treatment in previously naturally infected horses was therefore carried out. Two polo mares with clinical and virologically confirmed history of equine coital exanthema were injected with dexamethasone and prednisolone on 3 successive days. Clinical signs, body temperature and clinical samples for virological and serological studies were obtained daily. Mares did not show any systemic clinical signs or hyperthermia. EHV‐3 shedding, seroconversion and the presence of a small lesion were observed in one of the mares under study 2 weeks after corticosteroid treatment. The results demonstrate that this virus exhibits a latency‐reactivation behaviour similar to that of other alpha herpesviruses. Reactivation of latency may have an important bearing on the appearance of clinical signs in mares and/or stallions during the breeding season without the actual evidence of transfer from mare to stallion or vice versa.     

Living space in zoos--criteria for species-specific animal husbandry

Keeping wild animals in captivity is still object of criticism, above all due to the fact that room is restricted for these animals. But wild animal husbandry is basing on several factors: It has to concern physiological requirements as well as natural behaviour patterns, so as actions and reactions of wild living animals caused by ecological occasions have to be replaced by suitable arrangements. Most of the time proper animals husbandry is valued by quantity; in that way, that the measurements of artificial homes are often supposed to be more important than the quality of this enclosures. Optimal feeding, social structure, stimula for behaviour patterns like playing, breeding an rearing in calmness and well trained keepers are other basic requirements for wild animal husbandry. Criteria for keeping wild animals should not be scheduled by restrictive arrangements; innovations would be complicated by any regulations.     

Turbidity-induced changes in feeding strategies of fish in estuaries

The aim of this study was to determine the effect of turbidity on the feeding strategies of fish in estuaries. Three species representing different feeding guilds were selected for the investigation. These were Elops machnata (representative piscivore), Pomadasys commersonnii (a macrobenthivore) and Atherina breviceps (a planktivore). The stomach contents of these fish were examined from a clear and a turbid estuary and some experimental work was carried out on A breviceps to test the hypothesis that turbidity affects feeding behaviour. Turbidity was found to have no effect on size selection of prey, but feeding rate, particularly of visual predators, was reduced at higher turbidity levels. This was caused by a decrease in the reactive distance of the fish. It would appear that in order to optimize the aquisition of food under different turbidity conditions fishes have the ability to change their feeding strategies. Visual predators are more affected by turbidity than are macrobenthic feeders.     

Studies on Thysanura. II. Orientation Reactions of Machiloides Delanyi Wygodzinsky and Ctenolepisma Longicaudata Escherich to Temperature,Light and Atmospheric Humidity

Notes on the behaviour of six species of sparid fish, all rock reef dwelling, and forming an important section of the inshore line fish industry in the southern Cape, are given. It is shown that these fishes, although closely related, show very different feeding patterns. Notes on the breeding of Spondyliosoma emarginatum are given, and the male behaviour in nature is shown to differ from that observed in an aquarium.     

Contact dermatitis in dairy cattle caused by calcium cyanamide

Nine of 250 cows on a dairy farm initially developed severe dermatitis on parts of their bodies that touched the floor, and it then spread over their entire body. The cause was suspected to be calcium cyanamide, which had been added to the material spread on the floor to prevent environmental mastitis. Experimental exposure of the skin of a cow to calcium cyanamide induced the same type of contact dermatitis, and histopathological investigations showed that it caused irritant and allergic reactions. To identify the cause of the dermatitis, a patch test with calcium cyanamide and its breakdown products, cyanamide, urea and ammonium bicarbonate, was carried out on four cows. Three of them had a positive reaction to calcium cyanamide and cyanamide; delayed and amplified reactions suggesting an allergic response were observed.     

Rearing unit-level factors associated with bacterial gill disease treatment in two Ontario, Canada government salmonid hatcheries

Early-rearing salmonids in Ontario Ministry of Natural Resources (OMNR) fish hatcheries have been consistently affected by bacterial gill disease (BGD) (causative agent: Flavobacterium branchiophilum) for many years. Separate retrospective epidemiological investigations of BGD treatments at two OMNR fish hatcheries (Hatcheries A and B) for the 1999 production year were conducted using on-site hatchery records. Both investigations were carried out at the rearing unit-level, with early-rearing (<9 months of age) “tank-lot” as the unit of analysis to identify unique fish populations over time. Multivariable repeated measures logistic regression models were created for both hatchery datasets, controlling for lot-level and species effects. For Hatchery A, the species brook trout (Salvelinus fontinalis) and brown trout (Salmo trutta) were significantly associated with BGD treatment, as well as lower water exchange rate, and higher feeding and mortality percentages during the 2 weeks previous to BGD treatment. At Hatchery B, the species brook trout (S. fontinalis) and splake (Salvelinus namaycush × S. fontinalis) were significantly associated with BGD treatment, as well as lower individual fish weights and treatment for BGD during the previous week. These results emphasize the importance of water quality, feeding rate, fish size and prior mortality on the development of BGD. Significant hatchery and species effects were evident, and future observational research on BGD must account for these factors in their design and analysis.     

Preliminary investigations into the use of allergy skin testing solutions and desensitizing vaccines in dogs

Dogs suffering from chronic pruritus of unknown aetiology are a persistent problem for small animal practitioners. Many cases are classified as ‘allergic’ or ‘atopic’ even though little work has been carried out on the incidence or diagnosis of these conditions in Britain. Skin testing has been attempted but few published reports are available. Practitioners were supplied with skin testing kits containing a range of allergens to which dogs may be exposed and were asked to test clinical cases of pruritus which they considered might be of allergic aetiology. Positive reactions were obtained most commonly to house dust and house dust mite (Dermatophagoides pteronyssinus) antigens. In several cases the skin test results correlated with the symptoms and case history. Results suggest that in certain cases skin testing may be beneficial in diagnosis, although further immunological experimental work is necessary to evaluate more fully the technique. Desensitization therapy was attempted in several cases with fairly successful clinical results.     

Highly recurrent BRAF p.V595E mutation in canine papillary oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is the most common oral epithelial malignancy in dogs. It exhibits locally aggressive biological behaviour with the potential to metastasize, and a reported 1-year survival rate of 0% when left untreated. Expression studies suggest that aberrant MAPK signalling plays a key role in canine OSCC tumorigenesis, which is consistent with BRAF and HRAS MAPK-activating mutations reported in some tumours. Several morphological subtypes of canine OSCC have been described, with papillary, conventional, and basaloid as the most common patterns. We hypothesized that mutational differences may underlie these phenotypic variations. In this study, targeted Sanger sequencing and restriction fragment length polymorphism assays demonstrate that up to 85.7% of canine papillary OSCC (n = 14) harbour a BRAF p.V595E mutation. Assessment of neoplastic epithelial cell proliferation using Ki67 immunolabelling (n = 10) confirmed a relatively high proliferation activity, consistent with their known aggressive clinical behaviour. These findings underscore a consistent genetic feature of canine papillary OSCC and provide a basis for the development of novel diagnostic and targeted therapeutic approaches that can improve the quality of veterinary care.     

腺病毒的生物学特性

腺病毒在人和动物中广泛存在，是迄今在形态结构、基因组成和复制机理等生物学特性方面研究得最为详尽的病毒之一。就应用而言，对腺病毒载体进行的各种研究均是目前兽医学、医学和生物学的热门课题。本文就腺病毒生物学特性作一综述。     

Distribución de las arterias coronarias del toro de lidia

This study describes the left and right coronary artery distribution in the Spanish fighting bull, and compares the findings of the investigation with those of other bovine species in which similar investigations have been carried out. It is concluded that the general distribution of the coronary system in the Spanish fighting bull is similar to that of other bovine species which have been studied.     

Paratuberculosis and tuberculin tests

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Sir,—In his letter of April, 1964 (p. 38) Dr Tyndel's hypothesis is that, in the case he discusses, most of the reactions to the caudal fold tuberculin test may be as a result of sensitization due to Mycobacterium johnei and supports this by quoting the results of the complement fixation test for paratuberculosis carried out on sera from 25 tuberculin reactors and 25 non-reactors. Of the first 7 caudal fold reactors, 6 were positive to the short thermal test and tuberculosis was found in one of these animals at post-mortem examination.     

The immunogenic properties of Salmonella typhi-murium in sheep

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Salmonellosis of adult sheep due to infection with Salmonella typhi-murium was first recognized and confirmed bacteriologically in New Zealand in March, 1949. Since then, 100 outbreaks have been identified, most of which have occurred in the North Island. These outbreaks have occurred on farms varying in topography and under different conditions of management. With one exception, none of these outbreaks, which occur mainly in late Summer and Autumn, has been associated with transit by truck or rail journeys. In 1950, consideration was given to the possibility of affording protection by prophylactic vaccination, and the purpose of this paper is to record the results of some experiments carried out at Wallaceville and in the field with that object.     

Some effects of drugs in the “doping” of racehorses

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At the request of the New Zealand Racing and Trotting Conferences the writer has carried out tests on racehorses using some of the drugs found in positive samples by the analyst. Most of these tests were carried out in close co-operation with the analysts to the two Conferences and were undertaken because reliable data on the excretion patterns and effects of the various drugs could not be obtained. It is often important to know how and when the particular drug was administered, and these tests have proved a valuable guide. Some of their results have been surprising and it is hoped that the findings will be of general interest since any veterinary surgeon might find himself involved in an inquiry and it is important that he should be as sure as possible of all relevant factors before entering the witness box. It is easy to make sweeping statements at an inquiry but whoever makes them must surely be prepared to verify them. Any of these doping cases, however simple their early stages may appear, might proceed to the Supreme Court where rash statements could be legally challenged. In the writer's dealings with the New Zealand Racing and Trotting Conference he has found them to be scrupulously fair and only interested in finding out the truth. Their aim is to keep racing clean; we, as veterinary surgeons, should share that aim.     

Animal behaviour and scientific management

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Social animals—i.e., animals which associate in herds, flocks or packs—are an integral part of New Zealand farming systems. Each of these domestic species has peculiar behaviour patterns associated with the establishment of, and maintenance of the social bond, as part of their species-specific behaviour repertoire. Four examples of the interaction between species-specific social behaviour and present-day husbandry techniques are considered.