پژوهشهای علوم دامی (دانش کشاورزی)
سال:1394 | دوره:25 | شماره:4 |تعداد مقالات:21

BACKGROUND: By studying lipid and lipoprotein concentrations changes in the pregnant camels, methods can be found to reduce fertility problems and enhance reproduction efficiency in the species Bactrian camels.OBJECTIVES: This experiment was carried out to evaluate the effect of age, sex and pregnancy on serum lipid and lipoproteins in two humped Camels.METHODS: blood samples were collected from the jugular veins of 20 healthy camels according to their age (<10, 10-4 and >4 years), sex and pregnancy. Serum concentrations of total cholesterol (TC), triglyceride (TG), total lipid (TL), LDL-cholesterol, HDL-cholesterol and VLDL-cholesterol were evaluated.RESULTS: The concentrations of TG, HDL-cholesterol, LDL-cholesterol and VLDL-cholesterol in different age groups was significantly different (P<0.05). Age had a significant effect on the level of serum TG, HDL-cholesterol, LDL-cholesterol and VLDL-cholesterol of the camels, as in advanced ages, these parameters were lower except LDL-cholesterol. The concentration of LDL-cholesterol in immature camels was lower than adult ones. The concentration of TC was higher in male camels compared with females and this difference was significant (P<0.05). Tthe concentration of HDLcholesterol was higher in non-pregnant camels as compared with pregnant camels.CONCLUSIONS: Probably activation of sexual hormones during the puberty and hormonal interactions in the hypothalamus – pituitary - Gonadal axis (HPG) is the main reason for this phenomenon.

BACKGROUND: Study of heritability, genetic and phenotypic correlations of internal egg quality traits.OBJECTIVES: The aim of this study was to evaluate of heritability, genetic and phenotypic correlations of internal egg quality traits in Azerbaijan native fowls.METHODS: Statistical models for all traits were fitted using GLM procedure of SAS software. Fixed effects including generation and incubation time were significant (P < 0.01) for all traits except for yolk hright. In the first section, eight univariate animal models were compared for estimation of heritability and other genetic parameters and the most appropriate model for each trait was determined based on deviance information criterion (DIC). The genetic and phenotypic correlations between certain traits were also estimated through a multivariate animal model.RESULTS: Results showed that direct heritability estimations for egg quality traits ranged from 0.12 for Haugh unit to 0.46 for yolk depth. There were high positive genetic and phenotypic correlations between albumen height and Haugh unit (0.96) as well as between egg weight and albumen weight (0.87).CONCLUSIONS: Egg quality traits especially Haugh unit as a trait in the selection index, could be useful to improve internal egg quality in eggs of Azerbaijan native fowls.

BACKGROUND: Use of cooling systems can improve blood anti-oxidants of dairy cows during the hot weather.OBJECTIVES: This study was conducted to evaluate the advantages of cooling systems on immunity, oxidative status and cell blood counts of early lactating dairy cows during hot weather. METHODES: Forty six multiparous Holstein dairy cows were blocked according to milk yield and parity into two treatments after parturition as follows: group 1, the heat stressed cows and group 2, cows were housed in individual roofed boxes and were cooled 8 hours per day with sprinkle and fan.RESULTS: The production of oxygen free radicals (P<0.001), malonaldehyde (P<0.01) and activity of glutathione peroxidase (P<0.001) and superoxide dismutase (P<0.001) and total antioxidant capacity (P<0.05) were higher in group 1 in compared with group 2. But the concentrations of immunoglobulin A (P<0.01), immunoglobulin G (P<0.001), interlukin-1 (P<0.01) and tumor necrosis factor-alpha (P<0.001) in group 2 were greater than group 1. Furthermore, the hematological factors such as white blood cells (P<0.01), lymphocytes (P<0.05), monocytes (P<0.05), red blood cells (P<0.01), hemoglobin (p<0.05) and hematocrit percentage (P<0.001) were better for cows in group 2.CONCLUSIONS: With regard to these results, using of cooling systems can improve oxidative situation, immunity and hematological profiles of lactating dairy cows during hot weather.

Background: Increasing population and growing demand for dairy products and protein has led to paying more attention by policymakers in livestock sector on increasing efficiency. Objective: The purpose of this study is measuring technical and environmental efficiency of dairy farms in Sarab County and determining effective factors influencing them.Methods: Required data collected using simple random sampling and filling 51 questionnaires at year 1394.Results: Using Data Envelopment Analysis, average technical, scale and environmental efficiency calculated 95%, 55% and 88%, respectively. The Kruskal-Wallis test used to the statistical comparison of the difference between technical and environmental efficiency, Results confirm significant difference between them. Also, the result of Spearman's rank correlation coefficient show that the higher the technical efficiency of the farm, the less the pollution emitted and then the farm has high environmental efficiency.Conclusions: Finally, education and milk yield per cow determined as the effective factors influencing the environmental efficiency of dairy farms.

Background: livestock production as a protein source for human hasnot an equal elevation along with world population growth. Whereas different animal diseases have more confining effects on livestock production. Cystic echinococcosis as a zoonotic disease has direct and indirect influence on human health and meat production system, respectively. Objective: We investigated effect of time and area variables on economic losses of cystic echinococcosis based on hydatidosis data report of three abattoirs in south of Kerman province from 2011 to 2014.Methods: Database was registered information of three slaughterhouses of three cities from south of Kerman province. Economic losses evaluation was based on discarded offal price and indirect financial losses of meat and wool production decline resulted from hydatidosis disease. Result: The disease rate average was 5.4% during 4 years. Contaminated carcass rate was significantly different between three cities and different seasons (P<0.01). Disease had the most outbreaks during fall and winter seasons. Total economic losses were 58345080 Rial. Maximum and minimum loss was 64% for offal discards and 5% for wool production. Conclusion: although disease rate in these regions showed a decreasing trend, but total disease rate was partly critical. More disease control during farm animal production, exact carcass inspection and enhancement of public information about cystic echinococcosis for disease prevention is recommended.

BACKGROUND: The Subsidy Reform Plan (SRP) was implemented in 2010 in order to replace the subsidies on energy, food and etc with targeted social assistance.OBJECTIVES: Given the importance of dairy industry in human nutrition, the aim of this study is to evaluate the impact of ISRP on the efficiency and productivity of dairy farms.METHODS: Data were collected from a sample of 65 industrial dairy farms by using proportionate stratification sampling method, through face-to-face interviews based on a structured questionnaire. The calculation method of efficiency and productivity respectively are data envelopment analysis (DEA) and Malmquist index.RESULTS: The results show that respectively decrease and increase in technical and allocative efficiency of farms. In addition, farm productivity has declined in this period, but there was no significant difference between periods. There were significant differences between productivity and technical, allocative and economic efficiency of farms with different size. Furthermore, farms with more than 1,000 head of cattle has been less affected by the ISRP.CONCLUSIONS: In order to improve the dairy farm productivity and efficiency, and the farmer’s motivation, it is important to removal of the output price distortions and enhancing farmers' access to input markets.