Investigation and control of mastitis outbreaks caused by Pseudomonas aeruginosa in a sheep flock and a goat herd

Outbreaks of mastitis in a sheep flock and a goat herd caused by Pseudomonas aeruginosa, and their control are described.The morbidity rates of mastitis in a sheep flock and in a goat herd were 18.7 and 18.2 per cent, respectively. The lethality and involuntary culling rates of the animals with sub-clinical mastitis correspond to the morbidity rate.The highest morbidity rates were noted in yearlings--22.5 and 30 per cent, as well as in animals pre- and post partum (7 and 20 per cent, in sheep and goats, respectively). The morbidity periods in the flock and in the herd were 20 and 27 months, respectively. A strict-hygiene milking programme and maintenance of the milking devices was introduced. In addition, prevention of crowding, provision of dry bedding and thorough cleaning of water troughs have also been instituted. Ruthless culling of all infected and carrier animals was an essential part of the control program against Pseudomonas aeruginosa mastitis.     

Differences in the digestive tract characteristics of broiler chickens fed on complete pelleted diet or on whole wheat added to pelleted protein concentrate

1. The effects of whole grains of wheat on the digestive tract of broiler chickens was studied. A complete pelleted feed was compared with free choice feeding of whole wheat and a pelleted protein concentrate, given from 7 to 29 d of age. 2. Pepsin activity in proventriculus tissue was lower in whole wheat-fed birds than in complete diet-fed birds. The weight (g/kg body weight) of the gizzard was higher in whole wheat-fed birds and its contents had a lower pH. 3. In the intestine, there were no differences in deoxyribonucleic acid (DNA) concentration, protein/DNA, ribonucleic acid (RNA)/DNA, RNA/protein ratios or alkaline phosphatase activity expressed per tissue weight. The weight (g/kg body weight) of the duodenum was lower in whole wheat-fed birds and its contents had a higher pH. Also the activities of alkaline phosphatase and leucine aminopeptidase in the duodenum, and maltase in the ileum, expressed per unit of bird weight, were lower in whole wheat-fed birds. 4. These results suggest that whole grain feeding increases the chemical (pepsin in proventriculus) and physical (gizzard muscle) functionality of the upper part of the digestive tract but decreases the digestive capacity of the intestine. Higher gizzard functionality may play a positive role in the control of bacterial populations. The lower digestive enzyme activities in the intestine may be detrimental in situations of mucosal deterioration caused by intestinal disease.     

The prevalence of porcine cysticercosis in Eastern and Southern provinces of Zambia

The objective of this study was to determine the prevalence and importance of porcine cysticercosis in rural areas of Zambia. The study involved an abattoir survey of 1316 pigs at a slaughter slab in Lusaka and two field surveys in villages in Southern and Eastern provinces. Lingual examination of live pigs and visual inspection of their carcass as well as blood sampling for measuring circulating parasite antigen by enzyme-linked immunosorbent assay (Ag-ELISA) were used as parameters to measure infection. In the field surveys, a questionnaire was administered to every household whose pigs were examined to obtain information on pig husbandry practices and to study risk factors for the infection. Out of the 1316 pigs examined at the slaughter slab, 143 (10.9%) and 271 (20.6%) were positive by lingual examination and meat inspection, respectively. Most of the pigs were very heavily infected with predominantly live cysts. The field surveys revealed that eight (8.2%) out of 98 pigs from Southern province and eight (5.2%) out of 151 pigs from Eastern province were positive for cysticercosis by tongue palpation. Using the Ag-ELISA 20 (20.8%) and 14 (9.3%) pigs were positive in Southern and Eastern provinces, respectively. The questionnaire survey revealed poor pig husbandry practices, absence of meat inspection and control, poor knowledge of the disease and poor sanitation in the surveyed villages. The prevalence of pig cysticercosis found in this study ranks among the highest in the southern African region, in Africa and in the world. The current study suggests the presence of human tapeworm carriers and a high risk of human cysticercosis in the surveyed areas as well as in urban centres where pigs from rural areas are increasingly sold, slaughtered and consumed.     

Constraints under organic farming on French sheepmeat production: a legal and economic point of view with an emphasis on farming systems and veterinary aspects

Ovine meat production in France, which is continually regressing due to economic difficulties, is based on two main production systems. The first system is located in plains in which one part of the lambs born in the spring are fed grass, and the other part of the lambs are from out of the season parturitions following hormonal treatments and are fattened in sheep houses. The second system is represented by farms in the mountains using hardy breeds which have a natural faculty for out of the season breeding and whose lambs are fattened indoors, whatever the season of birth. Amongst the sanitary problems encountered, parasitism in particular of young animals, is crucial, especially for farms on plains practising grass fattening. These farmers systematically use conventional anthelmintic treatments, in particular against Moniezia and Strongyles. With organic farming, the limited number of conventional anthelmintic treatments is a strong constraint, especially for the management of young grass-fed animals. A study of 10 organic farming farms or farms converting to organic farming (six in the mountains and four in the plains) showed that the size of these farms is inferior to that of conventional ones and have technical performances which are comparable to the average with 20 to 30% extra over-prices on lamb sales. Despite this, the gross margins per ewe in organic farming are equal to the average of those for conventional farms. This is due to the high consumption of concentrate at a high cost (50 to 100% greater than that for conventional farms). Finally, to prevent sanitary risks, certain organic farmers use important amounts of feed supplements containing phytotherapy products whose costs burden a part of the financial results of the farm. On the contrary, other organic farmers are able, by adapting breeding and grazing managements, to significantly decrease animal health costs without increasing feed supplements nor decreasing zootechnical performances.     

Molecular epidemiology of a large classical swine fever epidemic in the European Union in 1997-1998

A big epidemic of classical swine fever (CSF) occurred in the European Community in 1997. The first case was reported at the beginning of January 1997 from Germany. The disease presumably spread to the Netherlands, and from there to Italy, Spain and eventually to Belgium. About 30 isolates from these outbreaks were analysed by comparison of the nucleotide sequence data generated from fragments of both the E2 glycoprotein gene (190 nucleotides) and from the 5'-nontranslated region (5'-NTR; 150 nucleotides). By combining epidemiological data with genetic typing, it was found that the outbreaks were related and caused by a virus belonging to the genetic subgroup 2.1. As this type of virus had been reported infrequently in Europe and not at all since 1993, we postulate that it was newly introduced into the European Union (EU).     

Alveld-Producing Saponins: II. Toxicological Studies

The phototoxic lamb disease alveld, prevalent in South-Western Norway, is caused by ingestion of Narthecium ossifragum. Earlier studies have shown that peroral administration of large amounts of crude saponins from this plant elicits the disease. Such saponins have now been purified further by 2 different methods (A and B). Two A type preparations resulted in alveld when fed to 2 lambs. The most highly purified preparation (type B) did not cause alveld in the 2 lambs tested. Lambs vary, however, in their susceptibility to the disease. Both types of preparations led to increases in serum aspartate aminotransferase, bilirubin and 5′-nucleotidase in rats when injected intraperitoneally in amounts of 50 or 100 mg/kg body Weight. Cannulation of the bile duct showed that injected saponins reduced both the volume of bile and the amounts of bilirubin and bile acids excreted. Histological changes seen in the light microscope were, except for the most peripheral parts of the liver, hardly noticable. These observations support the view that saponins are the liver-toxic agents responsible for alveld. The possibility is discussed that the effect arises through a change in the lipid environment of carrier-mediated transport systems.     

Mixed thymoma in a cow.

A neoplastic mass measuring 25 x 8 x 3 cm was found in the mediastinum of a 10-year-old Holstein cow. The neoplasm was encapsulated, multilobulated, and cystic. Several firm adhesions were present between the neoplasm and the right cranial lung lobe and the ipsilateral side of the pericardial sac. Under microscopic examination, the neoplasm was characterized by solid sheets of spindle epithelial cells (pancytokeratin and high molecular weight cytokeratin positive) subdivided by fibrous trabeculae. Numerous individualized or small aggregates of mature T-cell (CD3 positive) lymphocytes were scattered throughout the neoplastic cell population. Based on the gross, histologic, and immunohistochemical findings, the neoplasm was diagnosed as a mixed thymoma.     

Floral analysis cannot be considered as an alternative to the foliar diagnosis in the olive

Correlations between macro and micronutrient concentration of olive leaves and those obtained in floral buds at five development stages, were studied in order to evaluate the utility of floral analysis for the diagnosis of the nutritional status of olive orchards. Olive leaves from ‘Arbequina’, ‘Frantoio’, ‘Hojiblanca’, ‘Bella de España’ and ‘Picual’ cultivars were taken during July of 2002 and 2003. Samples of floral buds were collected at five development stages: closed bud (E), petal fall (G), G + 15 days, G + 30 days and pit hardening (H). Results showed a lack of signification of the correlation coefficients between leaf and floral analysis for N, P, K, Ca, Mg, B, Zn, Mn, Fe, Cu and Na in both years of the experiment. The few significant correlations obtained were not repeated in both years. Therefore, the results indicate that floral bud mineral analyses cannot substitute the foliar diagnosis to establish the nutritional status of the olive orchards.     

The effects of fructo-oligosaccharides or whole wheat on the performance and digestive tract of broiler chickens

1. The objective of this experiment was to study two feeding methods, which could potentially act on the gut microflora, the structure and/or the function of the digestive tract and thereby improve the performance of broilers. 2. Four dietary treatments were studied: a negative control (wheat based) with no additives (C), a positive control with 0.01 g/kg avilamycin (AV), a treatment with 0.6 g/kg fructo-oligosaccharides (FOS) and a treatment with the same composition as treatment C but in which a part or all (400 g/kg) of the wheat was given as whole wheat and a concentrate supplement (WW). The measurements were: the performance from 0 to 6 weeks, the bacterial counts at 3 and 6 weeks, the digestive tract morphology and the activity of some intestinal enzymes at 3 weeks. 3. The birds given AV had better daily live weight gain (DLWG) and feed conversion ratio (FCR) compared to treatment C. The birds given FOS had a lower feed intake and a lower DLWG than the birds on treatment C but their FCR was significantly improved. WW resulted in a numerically lower feed intake and a significantly lower DLWG than treatment C. With AV, the number of aerobic mesophilic bacteria in the caeca was reduced at 3 weeks. With WW, gizzard and pancreas weights were greater and the surfaces of the ileal crypts were larger. An increased activity of leucine aminopeptidase (LAP) in the duodenum was found for treatments AV, FOS and WW. 4. In conclusion, in this study, treatments WW and FOS reduced DLWG, which may have been due to a lower feed intake during the whole period. With WW, the FCR was not affected, maybe because of both positive and negative effects on digestive tract (higher gizzard and pancreas development and LAP activity; larger crypts). However, FOS improved FCR, which may be partly explained by the higher LAP activity.