Manganese-methionine chelate improves antioxidant activity, immune system and egg manganese enrichment in the aged laying hens.

BACKGROUND: It has been reported that supplementation of manganese (Mn) could alleviate the negative effects of age on egg quality in laying hens. However, limited information is available on compensatory ways in order to reduce the adverse effects of hen age on health and Mn deposition in the body. OBJECTIVES: The objectives were to investigate the effect of organic and inorganic sources of Mn on antioxidant activity, immune system, liver enzymes, shell quality and Mn deposition in the tissues of older laying hens. METHODS: A total of 250, 80-week-old Leghorn laying hens (w36) were allocated into five treatment groups with five replications in a completely randomised design. Treatments were control (without Mn supplementation), 100% Mn sulphate, 75% Mn sulphate + 25% organic Mn chelate, 50% Mn sulphate + 50% organic Mn chelate and 25% Mn sulphate + 75% organic Mn chelate. RESULTS: The groups fed 50 and 75% organic Mn chelate exhibited the lowest feed conversion ratio, as well as the maximum laying percentage, and egg weight and mass. Except to those fed 75% Mn sulphate, the hens received Mn supplements either as organic or inorganic, had higher immunoglobulin G and M compared with the control (p < 0.05). A significant elevation in the values of superoxide dismutase was observed in the hens receiving 50 and 75% organic Mn chelate when compared with the other treatments. The ALP activity decreased with increasing organic Mn chelate. Mn supplementation, either as organic or inorganic, increased Mn deposition in bone, egg yolk and shell, serum and liver. CONCLUSION: Dietary supplementation with 50-75% Mn-methionine has the potential to replace Mn-sulphate in laying hens' diet for improving eggshell quality, Mn deposition in the eggshell, antioxidant capacity and immune response, as well as improving laying performance, egg weight and feed conversion ratio.

Zinc supplementation improves antioxidant status, and organic zinc is more efficient than inorganic zinc in improving the bone strength of aged laying hens.

BACKGROUND: There have been some reports indicating that supplementation of zinc could alleviate the negative effects of age on egg quality in laying hens. However, information regarding these positive effects on health and zinc deposition in the body is limited. OBJECTIVES: The aim of the present study was to investigate the effect of organic and inorganic sources of zinc on the antioxidant activity, bone strength, and zinc deposition in the tissues of older laying hens. METHODS: In a completely randomized design, 175 Leghorn laying hens (w36) aged 80 weeks were allocated into seven treatment groups and five replications: control (without zinc supplementation), zinc sulphate treatments (15, 30, and 45 mg/kg), and organic zinc treatments (15, 30, and 45 mg/kg). RESULTS: There was a significant increase in feed intake in the zinc sulphate and organic zinc treatments compared to the control treatment (p < 0.05). The egg mass in organic and sulphate zinc showed a significant increase. The feed conversion ratio was decreased significantly in the organic zinc treatments (p < 0.05). Both organic and sulphate zinc supplements enhanced serum superoxide dismutase activity as an antioxidant index (p < 0.05). The cortical thickness of the tibia was improved in laying hens receiving 30 mg/kg organic zinc. Supplementation of zinc could lead to an increase in zinc deposition in tissues, and organic zinc boosts bone strength. CONCLUSION: Zinc supplementation can improve antioxidant activity, feed intake, and feed conversion ratio and enhance egg mass and optimal absorption of zinc in tissues. The use of 30 mg/kg organic zinc is recommended for improving the cortical thickness of the tibia in aged laying hens.

Effects of feeding rumen-protected amino acids on the performance of feedlot calves.

OBJECTIVE: This study was conducted to produce and evaluate protected amino acids (AAs) against degradation in the rumen with greater bioavalibility and without the problems associated with polymer coating and the effect this has on calf performance. MATERIALS AND METHODS: In the first step, essential AAs methionine and lysine were reacted with two chemical compounds (Benzaldehyde and Glutaraldehyde) in an attempt to make ligands for producing protected AAs. The physico-chemical characterization, melting point, and mass spectrometric of products were estimated. These products were fed to 36 Holstein dairy calves with 110 ± 0.50 kg of average body weight and an age of 110 ± 10 days. Calves were randomly assigned to six treatments. This study was done with six treatments as a completely randomized one-way design. RESULTS: Feed consumption and average daily gain were less for control animals and those fed methionine and lysine glutaraldehyde compared to other treatments. The largest chewing time was observed for methionine and lysine glutaraldehyde, respectively, and the least was control. There was no difference for energy consumption, dry matter intake, or blood metabolites among the six treatments. The greatest total protein content was related to methionine and lysine glutaraldehyde treatment and the least total protein was observed in control treatment. CONCLUSION: It can be concluded that the use of chemical methods to protect AAs can be applied and may have some beneficial effects.

WITHDRAWN:The Effect of Intermittent Watering on Performance, Blood Metabolites, and Nutrient Digestibility in Baluchi Lambs.

Objective: This study was conducted to evaluate the effect of intermittent watering on Baluchi lambs, regarding their performance, blood metabolites, and nutrient digestibility. Methods: Twenty male Baluchi lambs, 120 ± 5 days of age and 29 ±2.2 kg body weight were randomly assigned to four watering treatments: (T1) free access to water during the day, (T2) watered ad libitum twice a day, (T3) watered ad libitum once a day, (T4) watered ad libitum once every two days. The experiment lasted 42 days. Results: water restriction led to reduction in weight gain, DMI, water consumption, Water/DMI (p<0.05). Rectal temperature and respiration rate non influenced (p>0.05). aldosterone, cortisol, insulin hormone affected by treatments (p<0.05). Serum glucose, creatinine, total protein and globulin not affected (p> 0.05). while observed significant difference among T3 with other treatment in BUN (p<0.05). significant differences were observed in serum cholesterol and triglyceride between T4 and other groups (p< 0.05). There was a significant difference between T4 and T1 and T2 in albumin serum (p< 0.05). RBC WBC non influenced by water restriction (p< 0.05). However, PCV, MCV, MCH, MCHC and hemoglobin influenced by treatments (p< 0.05). sodium and chloride of serum was significantly higher in T4, and there were significant differences among the treatments (p< 0.05). But there were no differences among the treatments (p> 0.05), with regard to calcium, phosphorus, magnesium, potassium. Digestibility of ADF, NDF, CP and OM was different among T3, T4 and other treatments (p< 0.05), while no differences were found in EE digestibility among treatments (p> 0.05). There was a significant difference between T4 and other groups and between T4 and T1 regarding fecal output and urine exertion respectively. Conclusion: This results implies that Baluchi lambs can tolerate water restriction up to once a day for at least 28 days without harmful effects.