Showing papers in "Tijdschrift Voor Diergeneeskunde in 1999"

[Nutrition-related problems in pet birds]

Abstract: The detection and correction of dietary errors plays an important role in avian medicine. Examples of diseases caused in part by a deficiency or abundance of a nutrient include hypovitaminosis A in birds of the parrot (Psittacidae) family, hypocalcemia in the African grey parrot, goitre in budgerigars, and iron storage diseases in the minah and toucan. Hypovitaminosis A can lead to metaplasia of mucous membranes, which in turn can lead to chronic rhinitis and respiratory fungal infections. Vitamin A deficiency is caused by feeding a seed based diet. Seed mixtures are often deficient in calcium, and nutritional secondary hyperparathyroidism can develop if an additional source of calcium, in the form of ground shells, is not provided. Tetanic symptoms as a result of hypocalcemia are only seen in the African grey parrot and the timneh parrot. Over supplementation of vitamin D gives rise to poisoning with polyuria and polydipsia as common initial symptoms. The exact cause of iron storage diseases in toucans and minahs is not known. A diet low in iron and vitamin C is advised as therapy. Goitre can develop in budgerigars as a result of iodine-deficient drinking water and provision of a seed mixture based on millet. An unbalanced or multideficient diet can give rise to reproductive disorders, abnormal feathers, or infections as a result of diminished resistance. It is usually not possible to relate the cause of these diseases in a simple way to the composition of the diet. Obesity, which occurs in the galah, Amazon parrot, and budgerigars, can lead to fatty liver and lipoma. A gradual reduction in weight, by means of calorie restriction, is recommended. Commercially available nutritionally balanced bird food is often effective.

Voeding en vruchtbaarheid bij landbouwhuisdieren

Abstract: This paper deals with the reduction of fertility in cattle and pigs due to increased production. Special attention has been paid to the negative energy and protein balances during the first weeks post partum. It has been questioned which organs and organ systems become affected by the changes in these balances. For that study, the animal model of the overconditioned cow ante partum has been developed and used. The paper is dealing with possible effects on the hypothalamic-hypophyseal (HH) system and LH release, on the ovaries with secretion of steroids and release of properly matured oocytes, on the uterus as milieu for the embryo and on the immune system with leucocytes that play a role in follicle development and ovulation. The preliminary results of the first experiments open the discussion whether the reduction in fertility in this model is the consequence of the direct effect of glucose and insulin on the HH system and ovaries or of the indirect toxic effect of the non-esterified fatty acids, resulting from a temporary decrease of insulin, on granulosa cells and gametes.

[Veterinary assistance to dairy farms in the Netherlands: an assessment of the situation by dairy farmers].

Abstract: A questionnaire-based study was conducted among 466 dairy farmers in the Netherlands. The study investigated the experiences and opinions of dairy farmers about veterinary herd health and production management programmes. The dairy farmers were selected at random, and thus some took part in such programmes whereas others did not. The questionnaire comprised general questions about the farm operation and specific questions about the herd health programme and the practice conducting it, as well as perceived advantages and disadvantages of the veterinary programme. Farmers who did not participate in such programmes were questioned about their reasons for not participating. Both groups were questioned about future perspectives and opportunities. The costs of the programme appeared to be a drawback for participation but not as much as perceived by the practices. According to farmers, programmes focus too much on curative aspects and too little on analysis or prevention, where the needs are. Farm areas not included in the programme are so far not yet covered by other institutions, contrary to the expectations of the veterinarians. In the future, the farmers would be willing to take part in similar or expanded programmes, provided that certain conditions, such as product definition, structure, planning, costs, are properly met.

[Veterinary supervision of dairy facilities in the Netherlands: what do veterinarians think about participating and non-participating cattle owners?].

Abstract: Dairy herd health and production management programmes are being used increasingly more often, also in the Netherlands. However, little is known about the rationale behind the farmers' decision to participate or not to participate. This paper reports the results of a questionnaire survey among cattle practitioners about why they thought farmers did or did not participate in these programmes, the perceived advantages and disadvantages of such programmes, the extent to which the respective farming areas were represented in the programmes, and the reasons why farmers stopped participation in the programme. Furthermore, the ways in which the practitioners try to convince the non-participating farmers to join the programme were addressed. The future of dairy herd health programmes in the context of quality assurance programmes and the way the farmers think about these developments were discussed by the practitioners.

[Aortic rupture in poultry: a review].

Abstract: Mortality in poultry due to aortic rupture is characterized by sudden death. The condition is seen in fast-growing male turkeys but has also been described in chickens, ostriches, and waterfowl. Losses in affected flocks usually only reach 1-2%. Post-mortem examination shows a large blood clot in the abdominal cavity subsequent to a dissecting aneurysm. Fragmentation of elastic fibres and degenerative changes of smooth muscle cells are seen in the region of the rupture. Intimal sclerotic plaques are present adjacent to the site of rupture. Copper deficiency, hypertension, hormonal influences, diet, lathyrism, zinc deficiency, pharmaceuticals, and parasites are precipitating factors for aortic rupture. Field studies suggest that favourable results are obtained with reserpine and copper as treatment for ruptured aorta.

Nutrition of young piglets in relation to weaning problems

Abstract: Weaning at the age of 3-4 weeks has great consequences for piglets. The consequences of the change from milk to solid food are discussed with regard to the supply of nutrients, the available enzyme capacity of the digestive tract, and the morphological and functional changes in the gut. A number of preventive measures are discussed, with a distinction being made between general measures, measures related to the composition of the diet, and measures related to specific additives. Future research should clarify the mechanism of action of specific additives and pay more attention to the uptake of nutrients in piglets in the period just after weaning.

The electrosurgical treatment of endometrial cysts in the mare

Abstract: A minimally invasive technique for the removal of endometrial cysts is described. Intraluminal cysts hinder the migration of the embryo through the uterus in early pregnancy and in a later stage hinder placenta development and hence diminish the chance of successful pregnancy. Cysts can also give rise to false-positive results in early pregnancy tests. Endometrial cysts located in the lumen can be removed surgically from the standing mare. After placement of the endoscope, a wire is placed, via the biopsy channel, around the base of cyst, which is then cut through by cauterization. The cyst is removed with the help of forceps. Five barren mares with multiple cysts were treated in this way during the anoestrous period for October to February. Three of these mares became pregnant during the next oestrus period.

Risks of using cytostatic drugs in veterinary medical practice

Abstract: Little is known about the chronic health problems caused by working with cytotoxic drugs. These drugs, including mitotane (Lysodren), chlorambucil (Leukeran), and azathioprine (Imuran), are usually teratogenic but can also be mutagenic and carcinogenic. The principle governing working with cytotoxics is to keep exposure as low as possible (the ALARA principle, as low as reasonably achievable). The Dutch Arbo-wet (Factories Act) requires that employer and employee restrict exposure to a minimum. This necessitates relatively expensive facilities, trained personnel, and good procedures. The owners and other people close to the patient are also potentially at risk and should be told of this and informed about drug administration and the disposal of faeces, vomit, urine, saliva, and blood. The prescription and/or administration of cytotoxic drugs, including those that are used as immunosuppressive agents in veterinary medicine, should be restricted to specialist veterinarians who have adequate knowledge and appropriate facilities to work with these agents. A work group to establish standards for working with cytotoxic drugs in veterinary practice is advocated.

[Rhinopneumonia or mycotoxin intoxication? Neurologic phenomena in horses from a riding school].

Abstract: In the course of several days most of the 40 riding-school horses turned out in paddocks developed ataxia of variable severity. Five of these horses showed severe ataxia and tremors, became paralyzed and were euthanized. Eleven privately-owned horses which were stabled on the same premises showed no clinical signs. The most likely diagnosis seemed to be the 'neurological form of EHV1', although the signs were not entirely typical. A few weeks later a second outbreak occurred among the riding-school horses and one of the privately-owned horses also showed signs of ataxia. In the meantime it had been shown that EHV1 titers in paired serum samples had not increased and that the cerebrospinal fluid of one of the severely affected horses was normal. Toxicological examination of hay, delivered just before the first outbreak and stored for the winter, showed a significantly increased concentration of lolitrem B mycotoxin (5-6 mg/kg). The hay appeared to have been made of ryegrass used for lawns and playing fields. Retrospectively it became probable that this hay occasionally been fed to the horses just before the onset of clinical problems. It is concluded that the horses showed the 'ryegrass-stagger syndrome'.

[The prevention of pneumovagina and the effect of the Caslick operation on fertility: a retrospective study].

Abstract: Mares with a large vulvar orifice have an increased risk of pneumovagina, which is associated with reduced fertility. Treatment is by means of the Caslick operation, by which size of the vulvar orifice is reduced. Factors that influence the occurrence of pneumovagina are the age and fertility status of the mare. In this study the risk factors for pneumovagina and the effect of the Caslick operation on fertility were investigated. In 1994, 1995, and 1996 a total of 967 mares were sent for service at a stud. Of these mares, 116 underwent a Caslick operation. The operated mares were older than the non-operated mares. Mares younger than 5 years had a lower chance of pneumovagina than mares aged 5-12 years, but mares aged 13 and older had an increased chance. Foals and barren mares were more likely than maiden mares to develop pneumovagina. Fertility was 67% among the non-operated mares and 51% among the operated mares, even though, after the operation, the vulvar orifice of the operated mares was the same as that of the non-operated mares. This difference in fertility may be due to secondary endometritis that continues to exist after the operation. Further research is needed to determine whether mares with pneumovagina should also be treated for endometritis at the time of surgery.

[Nutrition of horses: digestion, energy and protein evaluation and nutritional standards].

Abstract: The diet of horses should cover the energy and nutrient requirements of these animals. The desired composition of the ration depends on its digestion in the equine gastrointestinal tract. Nutritional problems or diseases caused by incorrect composition of the ration or by incorrect feeding should be prevented. The digestion of carbohydrates, fats, and proteins in the different parts of the gastrointestinal tract is described. In addition, the recently introduced net energy and digestible protein evaluation systems for feeds, and the energy and protein requirements of horses are presented.

Udder health on dairy farms. 1. Results of a longitudinal study on 300 Dutch farms

Abstract: Udder health was studied in 300 dairy herds grouped in three categories according to the bulk milk somatic cell count. In all herds, lactating cows were housed in a free-stall barn during the winter. All herds participated in a three or four-weekly milk recording system, had annual production quota between 300,000 and 900,000 kg, and were stocked with cows of the Holstein-Friesian or Dutch Friesian breeds. The incidence of clinical mastitis was not different among herds with a low (< or = 150,000), middle (151,000 to 250,000), or high (251,000 to 400,000 cells/ml) bulk milk somatic cell count. Clinical mastitis caused by Gram-negative pathogens occurred more often in herds with a low bulk milk somatic cell count. Clinical mastitis caused by Staphylococcus aureus, Streptococcus dysgalactiae, or Streptococcus agalactiae occurred more often in herds with a high bulk milk somatic cell count; however, the incidence of clinical Streptococcus uberis mastitis was not different among the three herd categories. The differences in bulk milk somatic cell count between the categories could be explained by the management practices studied. The incidence of clinical E. coli mastitis was mostly related to housing, hygiene, and milking machine. The incidence of clinical Staphylococcus aureus mastitis was associated with factors that were related to the bulk milk somatic cell count and to factors of which it was not clear whether they were a cause or effect of the high incidence of Staphylococcus aureus mastitis. The incidence of clinical Streptococcus dysgalactiae mastitis was related to nutrition, milking technique, and milking machine. The incidence of clinical Streptococcus uberis mastitis was associated with housing, nutrition, and milking machine. Two groups of farmers and herds could be differentiated. The first group was identified as 'Clean and Accurate', and the second group as 'Quick and Dirty'. The relationship between these two groups and bulk milk somatic cell count category was high. However, the relationship between the two groups and the incidence of clinical mastitis was weak.

[HYPP: hyperkalemic periodic paralysis in the horse].

Abstract: Hyperkalaemic periodic paralysis(HYPP) is characterized by intermittent episodes of muscular tremor, weakness, and collapse, and is probably caused by abnormal electrolyte transport in the muscle cell membrane. During an episode of HYPP, most animals are severely hyperkalaemic. HYPP is a hereditary disease and occurs only in American Quarter horses or crossbreds. Because these horses are now being imported into the Netherlands, HYPP should be included in the differential diagnosis of horses showing signs of muscle tremor, paresis, or paralysis. The present article reviews the literature on HYPP and describes a case showing typical signs of the disease.

Metabolic insights and nutrition of poultry

Abstract: Excessive specialization and high production requirements place high demands on the metabolism of poultry A number of metabolic problems, such as disturbances of energy metabolism (affecting mainly hens) and mineral balance (affecting mainly laying hens), affect performance Nearly all these problems are multifactorial in nature, but diet, and in particular the interaction between diet and phenotype, plays an important role The problem of ascites in broiler hens is discussed in relation to external and genetic causative factors Genetic factors can be further subdivided into structural and functional causative factors This distinction has important consequences For example, sudden death syndrome can be distinguished as a separate entity Fatty liver syndrome in laying hens, and gout and urolithiasis in chicks and hens are briefly discussed Finally, some of the most important or most common skeletal problems affecting poultry, namely, tibial dyschondroplasia, battery fatigue, rickets, and chondrodystrophy, are briefly discussed in the context of the dietary factors that underlie these disorders or which can be used as treatment

[Characteristics of pedigree cat breeding in the Netherlands: breeds, population increase and litter size].

Abstract: A survey of the Dutch Cat Fancy was carried out to determine reproductive, patterns of pedigree cats. The data of the present study were obtained by questioning the pedigree registers of the cat clubs participating in the foundation 'Overleg Platform van de Nederlandse Cat Fancy'. The Dutch Cat Fancy registers 34 different cat breeds. From 1992 up to 1996 a total of 25.985 litters were registered. Over this period the number of litters increased from 4989 to 5313. Litters from Longhair and Exotic Shorthair cats comprised the biggest group and accounted for 55% of the total number of litters. However, over this period, the number of Longhair and Exotic Shorthair litters decreased by 9%. Litters from British Shorthair, Birman, Maine Coon and Norwegian Forrest Cat increased in number as did litters from small breeds such as Ragdoll, Bengal and Sphynx. Litters from Abyssinian, Siamese, Oriental Shorthair cats remained relatively the same. The average litter size of the total cat population, based on pedigree certificates, was calculated at 3.3 kittens per litter. For different breeds litter size varied from 2.7 (Longhair and Exotic Shorthair) to 4.3 (Burmese and Maine Coon). Taking into account an average age of 14 years, the total Dutch pedigree cat population was estimated at 240,000 viz. about 10% of the total cat population.

Stofwisselingsinzichten en voeding bij pluimvee

Abstract: Bespreking van een aantal stoornissen: ascites in de braadkuikensector, Sudden Death Syndrome, het vette leversyndroom bij leghennen, jicht en urolithiase bij kuikens en hennen, en tenslotte de meest voorkomende skeletproblemen in de pluimveesector: tibiale dyschondroplasie, batterijmoeheid, rachitisafwijkingen en chondrodystrofie

Analysis of survey data about the effect of vaccination of sows against blue pig abortion (PRRS) in the Netherlands

Abstract: Questionnaires were used to collect information on the experience of pig breeders with the vaccination of sows against PRRS. There was a 1-year interval between the two questionnaires. Sixty-two pig breeders returned the first questionnaire and 36 returned the second questionnaire. Before they started vaccination, 61% of the pig breeders sent samples to the laboratory of the Animal Health Service for investigation. At least one blood sample was positive for PRRS antibodies, but PRRS virus was not detected in any of the samples. Repeat breeding was the most important reason to vaccinate sows. On 54 farms (77%) sows were first vaccinated during the suckling period, on one farm (2%) sows were vaccinated during gestation, and on 7 farms (11%) all sows were vaccinated irrespective of their phase of reproduction. Repeat vaccinations were given during the suckling period on all farms. Mild side effects were reported on 16 farms (25%). Repeat breeding was the most important adverse reaction, followed by anoestrus. After 1 year, 58% of the pig breeders expressed satisfaction with vaccination. Twenty-eight pig breeders stopped vaccinating their sows in the first year, mainly because vaccination had no effect on the technical results. The effect of PRRS on the technical results of eight farms before and a year after vaccination was analysed. Although technical results were slightly better after vaccination, it was not clear whether this improvement was due to vaccination. From the results of this study it can be concluded that, without good diagnostic investigations, the routine vaccination of sows against PRRS is not economically viable in herds infected with PRRS virus.

Het belang van een goede diagnostiek voor rundertuberculose

Abstract: Informatie over bovine tuberculose: besmettingsroutes, pathogenese, diagnostiek, kenmerken bij immuunrespons, ELISA-betrouwbaarheid, bewaking en bestrijding in Nederland Op het uitvoeren van tuberculinatie met de lange naaldspuit wordt nader ingegaan

[Giardia, a potential cause of diarrhea].

Abstract: Diarrhoea is a common problem in young animals living in densely populated surroundings, such as kennels and catteries. One possible causative agent is Giardia. The aim of this article is to increase awareness of this parasite.

A South American tapir (Tapirus terrestris) with peritonitis

Abstract: A 6-year-old male tapir was admitted because it had been anorexic for 1 day. On admission, the tapir weighed 160 kg. Its rectal temperature was 32.4 degrees C, its heart rate was 120 beats per minute, and its respiratory rate was 12 breaths per minute. The elasticity of the skin was diminished. Haematological evaluation upon admission revealed a haematocrit of 0.63 L.L-1., 6.0 G.L-1 leucocytes with 40 per cent band neutrophils. The concentrations of urea nitrogen and creatinine in plasma were raised (18.9 mmol L-1. and 475 mumol L-1., respectively). Severe combined acidosis was apparent; the venous pH was 6.965, the bicarbonate concentration was 13.7 mmol.L-1., and the venous pCO2 was 8.6 kPa. No strongyle eggs were isolated from faeces by flotation, but a faecal sample yielded a positive culture for Pseudomonas aeruginosa. Urinalysis revealed proteinuria and the presence of leucocytes and renal epithelial cells. Treatment with fluids, TMP/S (17.5 and 3.5 mg/kg body weight, twice a day, respectively), and clenbuterol (0.56 microgram/kg body weight, twice a day) intravenously was unsuccessful and the tapir died 4 days after hospitalization. At necropsy, peritonitis due to a colon infarct as well as chronic bronchopneumonia and renal tubulonecrosis were found. The antibiotic susceptibility of the bacteria isolated (Streptoc. sp., E. coli, and K. pneumoniae) from the tapir post-mortem was assessed.

Navicular disease in the hind limb of a Warmblood horse

Abstract: A 12-year-old Dutch Warmblood mare was admitted to the clinic with a 1-month history of lameness of the left hind leg. After clinical and radiological examinations and an bursascopy, the diagnosis navicular disease was made. The therapy consisted of stallrest, non-steroidal anti-inflammatory drugs, and orthopaedic shoeing plus intrabursal injections of short-acting corticosteroids and hyaluronic acid. The therapy was repeated following recurrence of the lameness. According to the owner the horse is currently performing at its previous level.

[An integrated quality policy for and by (cattle) veterinarians: 2. A comparison with the quality policy of family physicians].

Abstract: The core of the integrated quality control policy of Dutch general practitioners is the development of treatment guidelines. These guidelines are the basis for assessing interventions and for improving quality. General practitioners took the initiative to prepare these guidelines without there being external pressure on them to do so. The quality control policy strengthens the position of this professional group by diminishing differences in therapeutic approach. The procedures followed for establishing guidelines, such as those for human medicine, are described and may be of use to veterinarians.

["Emerging" viral zoonoses in native animals who can be the host in the Netherlands].

Abstract: Viral zoonotic diseases can be defined as 'Viral diseases transmitted from vertebrate animals to man'. Viral zoonoses have been emerging and re-emerging throughout history and can cause serious diseases and disease outbreaks in human populations. This paper deals with emerging viral zoonotic infections that have hosts in native species and can be a hazard for the human population in the Netherlands. Rabies virus, hantavirus, influenza virus tick-borne encephalitis virus, borna disease virus and prions will be discussed.

[An integrated quality policy for and by veterinarians: 1. Status of business].

Abstract: Several initiatives are being developed by the livestock industry and veterinarians to improve quality. This article describes the term quality control. Although action has been taken to improve quality, at the moment there is no integrated policy of quality control for veterinarians. To date, initiatives have been limited to defining the preconditions for such policies and little has been done to establish the content of veterinary interventions.