Soybean: feed quality and safety. Part 2: Pathology of soybean feeding in animals. A review

Abstract

Various animal models in farm and laboratory animals indicate the possible pathological effect of soybean feeding. Immunity and tolerance to oral soybean intake and a generalised meta-model of effects are discussed. It seems that FAO/WHO recommendations will have to be considered in assessing the biological value of soybean feed sources. Determination of hull content, antigenic potential, conglycinin and trypsin inhibitor content is warranted in view of the future component pricing of soybean meals.Key words: Soybean, villus height, antibody to soybean antigens, feed antigens, immune tolerance to feed, soybean pathology model, soybean allergy, component pricingIntestinal pathology in soybean fed animals McGuinnes et al. (1987) observed that rats fed on raw soybean meal developed enlarged pancreas and hyperplastic nodules which turned to adenomas and carcinoma. The effect was attributed to trypsin inhibitor effect, due to increased cholecystokinin plasma levels. According to Grant et al. (1987) the effect of pure soybean trypsin inhibitor on pancreas hypertrophy was less pronounced when it was fed in the form of soybean meal.Mice fed on raw soybeans survive only for weeks (Gee and Morgan, 1993). Feeding raw soybeans increases duodenal mucosa and smooth muscle layer thickness, but heat treatment significantly reduces this effect. Small intestinal weight is significantly increased in mice fed raw soybean meal (2.242 g vs. 1.410 g). A similar difference was observed in pancreas weight (0.547 g vs. 0.251 g). A similar effect was noted upon the administration of camostate (synthetic trypsin inhibitor), suggesting the role of trypsin inhibitors in the pancreas effect. However, small intestinal weight and structure are not influenced by camostate (unlike raw soybean meal), which suggests disparate effects on small intestine and pancreas. Pusztai et

Morphophysiological Adaptations of the Gastrointestinal Tract in Piglets Fed a Sesame Meal or Soybean Meal Diet

“…This may be caused by the higher fiber content and the presence of the trypsin inhibitor in vegetable proteins, as previously reported by Csaky and Fekete (2004). Furthermore, the experimental diets did not cause any detrimental effect on visceral weight of the experimental animals, which is similar to findings in other studies (Csaky and Fekete, 2004;Reis de Souza et al, 2007;Opapeju et al, 2008).…”

“…Li et al (1991) and Csaky and Fekete (2004) have observed similar effects in weaned piglets fed soybean meal diets. Zhan et al (2008) and Shan et al (2012) observed that dietary supplementation of arginine improved intestinal mucosa development in weaning piglets.…”

“…Previous studies have revealed the presence of certain allergenic proteins (glycinin and β-conglycinin), lectins and trypsin inhibitor in soybean meal (Csaky and Fekete, 2004;Purushotham et al, 2007), all of which can decrease jejunal villus height, as observed in piglets receiving SBM diet. Li et al (1991) and Csaky and Fekete (2004) have observed similar effects in weaned piglets fed soybean meal diets.…”

The Metabolizable Energy Value, Standardized Ileal Digestibility of Amino Acids in Soybean Meal, Soy Protein Concentrate and Fermented Soybean Meal, and the Application of These Products in Early-weaned Piglets

“…However, the presence of antigenic proteins such as glycinin, β-conglycinin and anti-nutritional factors such as TI and lectins in soybean could cause hypersensitivity for newly weaned piglets which may decrease nutrient availability and therefore restrict its’ inclusion in diets fed to weaning pigs (Li et al, 1990; Csaky and Fekete, 2004; Hao et al, 2010). …”

Distribution of isoflavones and coumestrol in neglected tropical and subtropical legumes

“…Their therapeutic and/or preventive virtue, based partly on the ability to bond with estrogenic or androgenic receptors, is exerted especially in anticancer mechanisms (prevention and lower incidence in hormone‐related types of cancer), regulation of cardiovascular complaints and osteoporosis, antimicrobial protection and alleviation of postmenopausal disorders (with the possible use as an alternative to hormone replacement therapy) . Although isoflavonoids have a considerable number of positive health effects, they were first noticed in the first half of the last century, when reproduction problems had been noted in animals grazing on clover‐rich pastures …”