Comparison of the effects of dietary supplementation of flavonoids on laying hen performance, egg quality and egg nutrient profile.

1. The aim of this experiment was to compare the effects of dietary supplementation of hesperidin, naringin and quercetin on laying hen performance, egg quality and egg yolk lipid and protein profiles. 2. A total of 96 Lohmann White laying hens weighing an average of 1500 g at 28 weeks of age were randomly assigned to a basal diet and the basal diet supplemented (0.5 g/kg) with either hesperidin, naringin or quercetin. Each treatment was replicated in 6 cages in an 8-week experimental period. Data were analysed using one-way analysis of variance. 3. None of the dietary flavonoids affected laying performance and eggshell quality. Hesperidin and quercetin supplementations decreased albumen and yolk indexes. 4. As compared to the control group, egg yolk cholesterol content decreased and egg yolk protein content increased in response to dietary hesperidin and quercetin supplementation. The mean egg yolk cholesterol (mg/g) and protein (g/100 g) contents were 10.08/14.28, 16.12/14.08, 14.75/15.04 and 15.15/14.85 for the control group and groups supplemented with naringin, hesperidin and quercetin, respectively. 5. Egg yolk lipid and protein profiles were variable. 6. In conclusion, dietary supplementation of hesperidin or quercetin could be used in the diets during the early laying period to reduce egg yolk cholesterol and increase egg yolk protein, which may be attractive to consumers.

Effects of antioxidant vitamins (A, D, E) and trace elements (Cu, Mn, Se, Zn) on some metabolic and reproductive profiles in dairy cows during transition period.

The objective of this study was to determine the effects of some antioxidant vitamins and trace elements on some metabolic and postpartum reproductive profiles in dairy cows during transition period. In the study, altogether 20 clinically healthy Brown Swiss dairy cows (aged 4-5 years-old) under the same management and feeding conditions in periparturient period were used. The animals were divided into two equal groups: control (C) and treatment (T) group (n=10 for each group). Vitamins (A, D, E) and trace elements (Cu, Mn, Se, Zn) were administered intramuscularly into the cows of the T group, while isotonic saline, as placebo, was injected subcutaneously into those in the C group. Blood samples were collected by venipuncture of the jugular vein at the beginning of transition period, parturition and 3-weeks after the parturition. The metabolic and reproductive parameters were determined. In the C group, statistically significant changes were observed in the levels of non-esterified fatty acids (NEFA), high density lipoprotein (HDL), low density lipoprotein (LDL), total protein (TP) (p<0.05), glucose (GLU), progesterone (P4) (p<0.01), total cholesterol (T.CHOL), triglycerides (TG), UREA, creatinine (CRSC) and total bilirubin (TBIL) (p<0.001). In the T group, significant changes in the levels of NEFA, TBIL (p<0.05), T.CHOL, HDL, LDL (p<0.01), TG, GLU, P4, TAC and TOC (p<0.001) were observed. It was concluded that the administration of various vitamins and trace elements could be effective to improve some metabolic and reproductive profiles in dairy cows during the transition period.

Evaluation of 4 point-of-care units for the determination of blood l-lactate concentration in cattle.

BACKGROUND: Despite being used commonly in bovine medicine, information on reliability of point-of-care (POC) lactate meters is limited. OBJECTIVE: To determine the validity of 4 commercially available POC lactate meters in cattle. ANIMALS: Cattle with various diseases (n = 120). METHODS: Blood samples collected from the jugular vein were processed immediately on POC lactate meters. Plasma l-lactate concentration was measured by the enzymatic-colorimetric method (ELISA). Data were subjected to Friedman's test for comparison, Passing-Bablok regression and Bland-Altman plot analyses for reliability, and receiver operating characteristics analysis for sensitivity (Se) and specificity (Sp). RESULTS: The POC lactate meters were highly correlated with ELISA (r = 0.98-0.99) despite disagreements among units. When regressed on ELISA, blood l-lactate concentrations generated from Accutrend Plus and Lactate Pro were linear up to 16.6 and 15.7 mmol/L, respectively, whereas those generated from i-STAT and Lactate Scout were linear up to 19.5 and 19.7 mmol/L, respectively. All POC lactate meters had a Se of 100% with Sp of 95.7-98.6% at a plasma l-lactate cut-off concentration of 4 mmol/L. i-STAT had the best accuracy (99.0%) and precision (99.8%), the best linear fit (y = -0.13 + 1.04X) yielding the lowest bias (-6.6%) as well as the highest Se (100%) and Sp (98.6%). CONCLUSIONS AND CLINICAL IMPORTANCE: Despite high correlation with the reference method, dilution is needed for Accutrend Plus/Lactate Pro and i-STAT/Lactate Scout if concentrations >15 and 20 mmol/L, respectively. i-STAT provided the most accurate and precise results.

Investigation of lectin activity in Theileria annulata piroplasms.

Adhesion to target cells is an essential step in the pathogenesis of many protozoal infections. Some protozoa have been reported to have a lectin activity involved in their attachment to the cell surface. The ligand-receptor interaction involved in Theileria annulata infection is unclear at present, in spite of the fact that some aspects of the process have been investigated. To this end, T. annulata piroplasms have been screened for lectin activity. Blood taken from infected cattle was first depleted of leukocytes and then subjected to ammonium chloride lysis in order to isolate the piroplasms. The piroplasms were homogenised and a crude membrane extract was prepared by centrifugation. To investigate lectin activity in piroplasm proteins, a simple screening procedure was employed for analysing piroplasm proteins binding to various lectin ligands. Numerous immobilised lectin ligands (L-fucose-sepharose, N-acetyl-neuraminic acid-sepharose, N-acetyl-D-galactosamine-agarose, N-acetyl-D-glucosamine-agarose, D-mannose-agarose, beta-D-glucose-agarose, alpha-methyl-D-mannoside-agarose) were incubated with T. annulata piroplasm crude membrane extract. The ligand-bound proteins were eluted and separated by a brief centrifugation and determined by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). The present study suggests that a 32 kDa protein of piroplasm binds to D-galactosyl residues of the agarose matrix and that the binding is inhibited by galactose and not by the other monosaccharides tested.