M.J.A. Nabuurs

Effect of fermented soya beans on diarrhoea and feed efficiency in weaned piglets

Aims: To evaluate anti‐diarrhoeal and growth enhancing properties of fermented soya beans in weaned piglets.

Inhibition of adhesion of enterotoxigenic Escherichia coli K88 by soya bean tempe

Aims: Tempe is a traditional fungal fermented food made from soaked and cooked soya beans. It has been associated with antidiarrhoeal characteristics. This study investigated potential inhibitory effects of tempe on enterotoxigenic Escherichia coli (ETEC) K88. 
Methods and Results: Soya beans were soaked, cooked and subsequently fermented using several Rhizopus spp. Water‐soluble filter‐sterile extracts were tested for their ability to inhibit growth of E. coli and several indicator microorganisms and to inhibit adhesion of ETEC K88. Antimicrobial activity was found against Bacillus stearothermophilus only. ETEC K88‐induced haemagglutination of hamster red blood cells was strongly inhibited by a number of tempe extracts and hardly by the cooked soya bean extract. Furthermore, several tempe extracts were able to inhibit adhesion of ETEC K88 to piglet small intestinal brush‐border membranes. 
Conclusions: Tempe appeared to interfere with ETEC K88 adhesion rather than showing growth inhibitory properties. 
Significance and Impact of the Study: The results indicate that tempe could exert an antagonistic effect against ETEC through inhibition of adhesion and might therefore have a protective effect against ETEC K88 infection in pigs. Hence, tempe could have potential to use as a feed supplement in the diet of weaned piglets.

A review of porcine pathophysiology: a different approach to disease.

Abstract Diseases are often thought to result from a single cause. Although this is sometimes the case, e.g. with a highly virulent infection such as Classical Swine Fever (CSF), more often clinical disease in swine herds results from multiple predisposing factors. This is especially true in modern intensive pig husbandry, in which the role of highly infectious diseases is limited to (nonetheless devastating) outbreaks. More important nowadays are diseases, although associated with an agent, without a clear pathogenesis. The emphasisin disease control thusfar has been on treatment, eradication and prevention. This has been achieved by focusing attention on husbandry factors, such as climate, housing, hygiene, management, and nutrition. Although this approach has been successful for a number of diseases, several health problems are persistent. There are strong indications that in the latter, intrinsic animal factors are important. Successful handling of these problems requires knowledge of the (patho)physiology of the pig. In this article, several characteristics of pig physiology associated with the occurrence of disease are described. It appears that the modern (fattening) pig is exceptional among other animal species in that its cardiovascular system is mismatched to its body weight. It is argued that this particular disposition causes relatively minor disturbances to have major consequences in the pig. This concept of pig physiology is central to the understanding of the hitherto poorly understood pathogenesis of several diseases, such as oedema disease.

Effect of processed and fermented soyabeans on net absorption in enterotoxigenic Escherichia coli-infected piglet small intestine.

Infectious diarrhoea is a major problem in both children and piglets. Infection of enterotoxigenic Escherichia coli (ETEC) results in fluid secretion and electrolyte losses in the small intestine. In the present study the effect of processed and fermented soyabean products on net absorption during ETEC infection was investigated. Soyabean was processed into an autoclaved, a cooked and a mould-fermented (tempeh) product. The soyabean products were pre-digested and the effect of the products on net absorption in the small intestine of piglets was studied. Pairs of small-intestinal segments, one non-infected and the other ETEC-infected, were perfused simultaneously with the different products during 8 h. Net absorption of fluid, DM, Na, chloride, K and total solutes was determined. Net fluid absorption was highest for cooked soyabean followed by autoclaved soyabean and tempeh as a result of the osmolality of these products. In ETEC-infected segments, cooked soyabean and tempeh showed minor fluid losses (27 (SE 23) and 43 (SE 20) microl/cm(2), respectively) compared with the saline control (260 (SE 23) microl/cm(2)). Tempeh resulted in a high uptake of solutes. Processed soyabean products, particularly cooked soyabean and tempeh, are beneficial in maintaining fluid balance during ETEC infection. Additionally, tempeh showed high DM and total solute absorption. Therefore, particularly, tempeh may be beneficial in the case of post-weaning diarrhoea in piglets and possibly in children as well.

Comparative Toxicity of Three Quinoxaline-di-N-dioxide Feed Additives in Young Pigs

The quinoxaline-di-N-dioxide derived feed additives carbadox, olaquindox, and cyadox are widely used as growth promoters in modern pig husbandry (Aumaitre and Raynaud 1978; Bronsch et al. 1976; Herzig et al. 1984). Carbadox and olaquindox have also been demonstrated to protect against several enteric pathogens such as Treponema hyodysenteriae, an anaerobic spirochete involved in the pathogenesis of swine dysentery (Blobel and Schliesser 1979). In earlier studies from this institute it was demonstrated that doses of carbadox in feed of less than twice the recommended one of 50 ppm induced toxic side-effects, causing specific adrenal lesions (Van der Molen et al. 1985), and it was suggested that carbadox interacts with the biosynthesis of aldosterone (Van der Molen et al. 1986a, b).

Pharmacology of carbadox in the pig

An evaluation has been made of the in vitro minimal inhibitory concentrations (MIC) of carbadox against various bacterial species in relation to the carbadox levels obtained in the gastrointestinal tract and in the blood after in-feed medication of carbadox. Although a prophylactic efficacy against orally transmitted enteropathogenic spirochaetes and anaerobic bacilli seems warranted, no justification for the therapeutic application of carbadox was found. In fact, therapeutic dosages were found to induce hypoaldosteronism in young pigs. A direct anabolic action of carbadox could not be reproduced in healthy young pigs fed a standard commercial feed. The widespread use of carbadox in pig husbandry constitutes a selection pressure towards Escherichia coli strains with MIC values above the carbadox levels in the small intestines. Carbadox R-plasmids in E. coli strains can be transmitted to other gram-negative bacilli but not to Treponema hyodysenteriae. Prevention of swine dysentery seems now to be the only indication for in-feed administration of carbadox. A lower dosage and a shorter treatment period than those currently advised might provide a marginal safety factor while still being effective.