Effects of n-3 fatty acids on growth, antioxidant status, and immunity of preweaned dairy calves.

This study aimed to estimate the influences of flax oil and a mixture of ethyl esters of fatty acids from flax oil added to a milk replacer (MR) formulation on the biochemical, immunological, and antioxidant status of blood, production parameters, and health of calves. Twenty-seven Holstein-Frisian calves were assigned to 3 groups: the control group without fat added to the diet (CON, n = 9), a group receiving ethyl esters of flax oil (10 g/d) with lyophilized apples (25 g; MRE), or a group receiving flax oil (10 g/d) with lyophilized apples (25 g; MRL). The study was conducted from d 14 to d 42 of life. Intake of MR and feed were recorded daily, and fecal scores, rectal temperature, and body weight were recorded weekly. Laboratory blood tests were conducted every 7 d from d 14 to 42. Supplementation with the formulation containing ethyl esters of flax oil (MRE) positively affected health, average daily weight gain, growth rate, and feed efficiency. Intake of the starter feed was lower in the calves receiving the formulation with flax oil (MRL). The MRE formulations lowered the concentrations of triglycerides, total cholesterol, and LDL fraction in blood serum and decreased the total antioxidant capacity (TAS) and levels of glutathione peroxidase (GPx). The MRL formulation increased TAS and GPx levels in blood serum. The MRE treatment limited the circulating levels of tumor necrosis factor. The MRE and MRL preparations lowered the concentration of SFA (C16:0, C18:0, C18:1) in blood serum, and MRE significantly increased levels of α-linolenic acid. The MRE and MRL preparations beneficially affected production and physiological parameters. Our data support the idea that supplementation with n-3 fatty acids improves calf growth and metabolic and oxidative functions in young calves.

Effect of humic-plant feed preparations on biochemical blood parameters of laying hens in deep litter housing system.

An influence of various humic-plant feed additives based on some herbs (nettle, chamomile, yarrow, perforatum), lucerne and humic materials on biochemical indices of Lohmann Brown (LB) layers blood plasma was estimated. Hens were housed in deep litter system, 20 birds in a group. Four groups were formed: control (C - standard feeding), and experimental, supplemented with prepara- tions: E-1 herbal-humic, E-2 humic-herbal and E-3--humic-lucerne. Hens were placed in the pens on the 16th week of life, addition of preparations with standard food mixture started at the 22nd wk and lasted until 66th wk of life. Blood for analyses was collected four times in the following periods: 27, 37, 54 and 65th wk of life. The applied humic-plant preparations to a limited degree affected the values of examined biochemical parameters in serum: total protein (TP), albumins (Albs), glucose (Glu), urea, triacylglycerols (TAG), total cholesterol (TCh), alanine aminotransferase (ALT), aspartate aminot- ransferase (AST) and alkaline phosphatase (ALP). It is difficult to determine based on these study, which preparation is one the most active biologically, however is seems that humic-lucerne prepara- tion affected the examined blood parameters to the highest degree. The reference values ranges in hens blood serum LB hens were proposed for: TP (43-65 g/l), Albs (15-22 g/l), urea (0.5-1.2 mmol/l), Glu 10-15 mmol/l), TCh (2.2-4.5 mmol/l), TAG (10-24 mmol/l), AST (4-12 U/l), ALT (150-280 mmol/l) and ALP (190-350 U/l).