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Plant-based simple phenolics are natural antimicrobial and antioxidant compounds that may possess biological activity when included in animal diets. Previous work in our lab has shown that sinapic acid (SA) found in canola meal improves nutrient retention and alters gut microbiota when fed at low levels (0 to 0.10%) to broiler chickens. It was of interest to investigate the effect of dietary SA in laying hens that possess a more mature intestinal microbiota. Therefore, 2 experiments were conducted to determine the effects of dietary SA on performance, nutrient digestibility, and egg quality in laying hens. Sinapic acid (Sigma-Aldrich, 98% purity) was included in diets at 0, 0.025, 0.050, and 0.075% in experiment 1, and 0 and 0.5% in experiment 2. Both experiments were conducted for 21 d. Dietary treatment did not affect production traits and gastrointestinal tract volatile fatty acid production in either experiment. Apparent metabolizable energy and protein digestibility were also unaffected by treatment in experiment 1, but in experiment 2, feeding 0.5% SA increased both AME(n) and protein digestibility in comparison to the unsupplemented control. Egg weight, albumen weight, yolk weight, egg specific gravity, shell thickness, and Haugh units were not significantly affected by dietary treatments in either of the experiments. Sinapic acid was not detected in eggs from experiment 1 but in experiment 2, low levels of SA were detected in both the yolk and albumen of eggs from hens fed 0.5% SA. Further research is needed to more completely define the relationship between dietary SA level and nutrient utilization as well as the accumulation of SA in egg components.

Modern strains of fast-growing meat type poultry are highly susceptible to heart failure. Heart-related mortalities are observed predominantly in fast-growing broiler chickens, with ascites and sudden death syndrome being the most common heart-related conditions in modern broiler flocks. This paper examines the role of structural, molecular, and biochemical factors pertinent to the pathophysiology of heart failure in fast-growing broilers. Evidence explaining the pathogenesis of acute and chronic heart failure, in the context of the underlying molecular and biochemical changes in the cardiomyocytes, contractile apparatus, and extracellular matrix in the ventricular myocardium are critically evaluated and discussed with reference to the clinical signs associated with deterioration of heart pump function. The secondary pathophysiological effects on the cardiovascular system, resulting from hemodynamic changes associated with the failing heart pump, are also reviewed and critically discussed.

Lectins are capable of altering intestinal morphology by binding to and disrupting the intestinal brush border membrane. They are also known to alter the weight of lymphoid organs. Therefore, we evaluated the effect of soybean lectin (SBL) on intestinal morphology and lymphoid organ weights of poults fed diets containing SBL. Dietary treatments evaluated in this study included a cornstarch and casein-based control (lectin-free) semipurified diet (PD) and semipurified diets containing 0.024 or 0.048% SBL (PDL and PDH, respectively). Experimental diets were fed from hatch to 14 d. Morphological evaluation of the intestine involved measurement of the villi height and perimeter, crypt depth, villus:crypt, and thickness of the muscle layer in the jejunum. Intestinal physical characteristics were also determined by measuring intestinal weight, length, and volume. Results indicated that 0.048% SBL in PDH increased villus:crypt and reduced total intestinal length in turkey poults. In addition, both the 0.024 and 0.048% dietary SBL levels reduced thymus weights. It was concluded that dietary SBL up to 0.048% enhanced intestinal development by increasing villus:crypt, but might alter the structural integrity of lymphoid organs.

This work examines the effects of lupine-based diets on the status of the host's riboflavin and zinc. Test diets contained 35% soybean meal (control) or raw (40%) or dehulled (35%) lupine seed meal and were isocaloric (13.4 MJ of AME/kg) and isonitrogenous (23% crude protein). Each diet was offered ad libitum to a group of 16 male commercial broiler chicks for 21 d, starting at 1 d of age. Broilers fed lupine diets had lower feed intakes and growth rates. All sections of the intestinal tract were significantly enlarged (P < 0.01) in all groups fed lupine-based diets in comparison with broilers fed the soybean meal diet, but there were no differences in the morphologies of the mucosa, submucosa, muscularis, or serosa. Increased size of the duodenum, jejunum, and ileum was predominantly attributed to the increase in length rather than intestinal tissue mass. Hence, the enlargement of the intestinal tract was consistent with physiological hyperplasia and not pathological remodeling and hypertrophy. Overall, broilers fed lupine-based diets had more viscous digesta than those fed the soybean meal diet, but the differences were statistically not significant. Blood plasma Zn concentration did not differ between broilers fed lupine-based diets and those fed soybean-meal-based diets, and all broilers fed lupine-based diets had significantly higher (P < 0.001) riboflavin concentrations. In this context, it is apparent that the bioavailability of these micronutrients from lupine diets is not compromised. Intestinal tissue hyperplasia may be interpreted as physiological adaptation to increase absorptive capacity and thus maximize absorption of essential nutrients in the face of antinutritional factors in the diet.

This study describes the adverse effects of dietary lupines in broiler chickens for which lupine seeds (Lupinus angustifolius) in raw, dehulled, or autoclaved forms were used as a replacement for soybean meal (SBM) in practical diets. Test diets contained 35% SBM (control) or raw (40%), autoclaved (40%), or dehulled (35%) lupine seed meal. All diets were isocaloric (3,230 kcal/kg AME) and isonitrogenous (23% crude protein). Each diet was offered ad libitum to a group of 16 (four replicates with four birds per replicate) day-old male broiler chicks for 21 d. Chemical analysis of lupine seeds showed no detectable levels of mycotoxins, and total alkaloid contents were below 0.01%. Decreased food intake and growth rate were the main signs observed in all birds fed lupine-based diets. These adverse effects were observed during the first week and persisted throughout the trial. Acute signs of toxicity were observed in four chicks fed the diet containing raw lupine seed during the first week of exposure. Initial clinical signs included leg weakness, lack of coordination, and torticollis. In later stages, during Weeks 2 and 3, some birds fed lupine-based diets showed signs of muscle paralysis and skeletal deformity. Postmortem examination did not show gross pathological changes associated with the dietary treatments. Liver microsomal cytochrome P-50 content was higher (P < 0.05) in birds fed the raw lupine-based diet (mean 0.56 pmol/mg protein) in comparison with controls (mean 0.25 pmol/mg protein), which indicated a systemic effect. Based on the present results, it can be stated that high levels of some varieties of sweet lupines in broiler diets may cause significant adverse effects manifested as 1) decreased feed intake and growth rate in most of the birds, and 2) specific signs of acute and chronic toxicity in some individuals.

Relative efficacy of thiamine (B1) and/or calcium disodium ethylinediaminetetraacetate (EDTA) administration on lead (Pb) excretion via bile and urine was studied in Pb-loaded sheep. The sheep were administered B1 s.c., 75 mg/kg body wt., EDTA i.v., 110 mg/kg body wt., and a combination of B1-EDTA at rates as above. Each treatment was followed by 69 h sampling of blood, bile, and urine. Urinary Pb excretion increased following B1-EDTA greater than EDTA greater than B1 administration. Thiamine and B1-EDTA treatments increased biliary Pb excretion. Overall, B1, EDTA and B1-EDTA administration increased Pb excretion via bile and urine by 72%, 595%, and 842% respectively over basal level (mean +/- SE: 20.1 +/- 2.9 micrograms Pb/h). It has been concluded that thiamine enhances elimination of Pb from the body and this feature may be beneficial in chelation therapy.