فهرست مطالب نگار هدایت

Because of the particular role of vitamin A in different tissues and organs, various clinical signs are seen in its deficiency. Additionally, marginal deficiency of vitamin A without the presence of clinical signs leads to performance defects such as infertility. In this study, the seasonal changes of β-carotene and vitamin A of serum and liver of slaughtered sheep in Ahvaz abattoir were investigated. A total of 360 sheep were sampled from October 2013 to June 2014. Spectrophotometry was used for measuring values. The results were analyzed statistically with student t-test. The mean ±SE concentration of β-carotene and vitamin A of serum and liver were 209/9±1/5, 98±0/9 (µg/dl), 19/8±0/4, 32/3±0/8(µg/g), respectively. Although there wasnt significant difference in levels of the measured parameters in two age groups(sheep only with immature teeth and sheep with a minimum mature tooth) but there was a significant difference in vitamin A of serum and liver in the two sexes. The serumic levels of vitamin A in male sheep was more than the females while the concentration of vitamin A in the liver of female sheep was more than the males. The difference between seasons in vitamin A of serum was also statistically different with higher concentrations observed in warm seasons in comparison to milder seasons.

When the weather is getting cold in winter and according to temperature limitation, egg production decreases in rural areas and other avicultures that suffer from keeping optimal temperature quantitatively and qualitatively. According to this point that whey has a high dietary and probiotic value and in high volume is being produced in rural areas as an accessory product and often is being thrown away therefore; we can decrease cost of sustenance and conquest on cold stress with adding a natural valuable source, a probiotic substance, like whey to egg mash. The first priority in this study is determination of effectiveness about whey in laying of domestic fowls in winter and cold stress. In this study 90 domestic fowls in 38 weeks old and duration of 30 days were used. The study was completely random and with 3 cares and 3 repetitions (9 cages with 10cases in each of them) were done. The testable cares were in order: (1)the first group(witness) that received basal egg mash in total period (based on corn and soya) and was kept in 8-12c, (2)the second group received basal egg mash in total period and was kept in 16-20c, (3) the third group received basal egg mash with 5% solution of whey and was kept in a same temperature like witness group, then after 10 days from care performance, number of eggs and some of their qualitative indexes in each group were analyzed and measured. The results of this study show that the number of eggs in the second and the third group increased 60% and 50% sequentially, But; the noticeable point was that the eggs of third group had been increased in some indexes like average weight and although according to food consumption than the second group was in a same level but in point of quality has caused a statistically significant (P < 0.05). Thus with adding whey to egg mash of laying fowls can compensate some damage in reduction of egg production due to cold stress.