23 research outputs found
Relationship between birth weight and body growth characteristics of lambs
Research was carried out in population of R2 generation Pirot pramenka x Pirot improved sheep during period of three years. Lambs were divided into three groups: I from 2.5 kg to 3.5 kg; II from 3.6 kg to 4.5 kg; III from 4.6 kg to 5.5 kg. Weight of lambs was controlled at birth, with 30, 60 and 90 days of age. Average body weight at birth of the tested lambs was 3.35 kg in the first group, 4.30 kg in the second group and 5.06 kg in the third group. At 30 days of age, the body weight of the lambs was 10.19 kg in the first group, 11.39 kg in the second and 12.49 kg in the third group. All these differences in body weight of lambs at birth were statistically highly significant (P¬ 0.01). With 60 days of age, average body weight was 16.48 kg in the first group, 19.01 kg in the second and 20.49 kg in the third group. Differences between groups of lambs at this age were statistically very significant (P¬0.01).On the end of experiment at 90 days of lambs age, we have found the following values of the body weight of lambs: 26.35 kg in the first group, when the second 30.49 kg and 28.93 kg in the third group. Differences between groups of lambs at this age were statistically very significant (P¬0.01). At the age of 90 days maximum weight of the body was in the second group of lambs, or a group which body weight at birth occupied the mean of the population. Correlations between body weights of lambs vary from weak to midsized values. The highest values of correlation coefficients were found between body weight at birth and weight of lambs at 30 days of age
Crossing system application and its effect on lambs growth traits
Success of crossing depends on the breeds used and the genetic distance among them, as well the combining ability of maternal and individual heterosis to make the proper choice of breeds employed in a crossing system. The aim of this study is to find the effect of genotype and crossing system on early weights and daily gain of lambs. The lambs of purebred Pirot Pramenka ( P) got the lowest body weight at birth, at 30 days, at 60 days and 90 days with a value of 3.65 kg, 9.48 kg, 14.99 kg and 21.96 kg while purebred Wurttemberg attained the highest body weight at birth of 4.48 kg. The lambs of three bred crossing (PxWxF) highest on BW30, BW60 and BW90 days. The results showed a highly significant difference on average daily gain (ADG) among genotypes (P<0.01) except on the difference between W - PxW of which belongs to the lower border of significant level (P<0.05). The highest difference on ADG was between P - PxWxF (105.950 g), wherein the lowest difference was between W-PxW (9.290 g). It can close that the attained value between pure bred Wurttemberg (W) and two-bred crossing (PxW) was almost equal. Genotype and crossing system have significant effect on body weight and average daily gain of lambs. Based on the results obtained, it shows an advantage effect of crossing system (PxWxF) when it comes on growth and daily gain of lambs
The influence of the factor 'genetic value of the sire' on the implementation of the genetic potential of the indicator 'milk production of maximum lactation' of the Yaroslavl breed cows
Dairy products are the main food elements of the man. Milk is the sole food for infants and it plays an important role in feeding of the sick, convalescent, and healthy adults. The Yaroslavl Region is a leading region of the Yaroslavl cattle breed. Therefore, the aim of our research was to determine the strength and reliability of the influence of the factor 'genetic value of the sire' on productive characteristics of animals as a factor that helps to increase the productivity of animals. When we determine the strength of the influence of factors for statistical data we used the procedure of generalized linear models (General Linear Models - GLM), and evaluation components of phenotypic variation attributes were analyzed by multivariate dispersive analysis. Our research has allowed to allocate bulls with genetic value which has the improving effect. Using the recommended lines the farmers of the Yaroslavl region may increase productive characteristics of animals and the profit of the farms and improve the efficiency of breeding
Biochemical characteristics of Streptococcus suis strains isolated from healthy and deceased pigs
The aim of this study was to determine the biochemical properties of Streptococcus suis strains isolated from healthy and deceased pigs. For this research we tested 34 S. suis strains isolated from deceased pigs that had clinical signs of septicemia and meningitis, as well as from clinically healthy pigs. The strains that have been already confirmed with specific antisera were tested using commercial battery of biochemical tests (API 20 Strep and ID 32 Strep) to determine the dominant biochemical characteristics that can be used in diagnosis of bacterial infection if specific S. suis antisera are not available. The main results showed that all S. suis strains were postive in esculine, trehalose, glycogen, lactose, sacharose, starch, leucine aminopeptidase, alanine-phenyl-alanine-proline arylamidase tests, while negative in Voges-Proskauer, hipurate, ribose, arabinose and sorbitol tests. S. suis strains were in high percentage positive in arginine dihydrolase, β-glucoronidase, α-galactosidase, β-galactosidase, methyl-β-d- glucopyranoside, glycyl-tryptophan arylamidase and inulin tests. Athough S. suis is in highly positive in some tests, it can be concluded that Voges-Proskauer, hipurate, trehalose, esculine tests, along with β-glucoronidase (βGUR) and α-galactosidase (αGAL), were significant in differentiation of this bacteria from other similar streptococci, along with some other crucial features (a hemolysis on blood sheep agar, absence of growth in 6,5% NaCl broth)
Methods for determining stress syndrome in beef cattle and its relevance to quality of meat
Methods for determining stress syndrome in beef cattle is of great importance to identify the physiological state of young cattle before slaughter in order for such animals to be properly treated and restored to a normal physiological state. As a consequence of the state of stress prior to slaughter, meat is obtained which is different from normal. These are non-typical post-mortem changes in meat: 'PSE' (pale, soft, exudative) and 'DFD' (dark, firm, dry) meat, 'watery' meat, usually pork, and 'dark' mostly meat of young bulls. Tests were performed on bulls originating from a farm located 50 km from the slaughterhouse and another farm located 150 km from the slaughterhouse. Young bulls were kept in a free system and loading and unloading was done on unloading ramps and animals taken to the boxes using the lane corridor. Also, attention was paid to avoid mixing with unfamiliar animals during transport. The study included 20 males. The same vehicle was used to transport cattle from the farm to the slaughterhouse. The rectal temperature was taken from 20 young bulls, at the time of loading of cattle into a vehicle during transport and immediately before slaughter. The results of measurements of rectal temperature of investigated bulls suggest that prolonging of transport increases the rectal temperature which can serve as an indicator of stress syndrome in bulls. In addition to measuring of rectal temperature as an indicator of bulls' stress syndrome, other methods are still used, such as the measurement of cortisol in saliva and blood, or the latest methods of measuring cortisol in hair. This is the latest method of the 21st century, which can even determine the time of occurrence of stress. This method is the future that will determine whether the stress occurred few days, weeks or even months ago
The effect of genetic and non-genetic factors on production traits of Simmental cows
This study covered 737 controlled first calving Simmental cows with, lactations concluded within one year. All first calving animals were on the farms of individual farmers in the municipalities of Kragujevac and Mladenovac. The research included the influence of bull sires, year and season of calving on milk yield and fertility. Least squares method was used to determine the average duration of lactation of 323.74 days. For a period of 305 days, heifers produced 3701.67 kg of milk, or 3644.58 kg of 4% FCM. The average production of milk fat was 144.26 kg and milk fat content was 3.88%. The interval from calving to first insemination lasted in average 124.19 days, and the animals were first calved at the age of 789.95 days. The bull sires had a highly significant effect (P0.05) of bull sires. Year of calving had a significant effect (P0.05). Season of calving of cows demonstrated highly significant effect (P0.05) on the production of milk fat, however it had no effect (P>0.05) on the milk fat content, duration of lactation and service period and age at calving
Destruction of chemical warfare surrogates using a portable atmospheric pressure plasma jet
Today’s reality is connected with mitigation of threats from the new chemical and biological warfare agents. A novel investigation of cold plasmas in contact with liquids presented in this paper demonstrated that the chemically reactive environment produced by atmospheric pressure plasma jet (APPJ) is potentially capable of rapid destruction of chemical warfare agents in a broad spectrum. The decontamination of three different chemical warfare agent surrogates dissolved in liquid is investigated by using an easily transportable APPJ. The jet is powered by a kHz signal source connected to a low-voltage DC source and with He as working gas. The detailed investigation of electrical properties is performed for various plasmas at different distances from the sample. The measurements of plasma properties in situ are supported by the optical spectrometry measurements, whereas the high performance liquid chromatography measurements before and after the treatment of aqueous solutions of Malathion, Fenitrothion and Dimethyl Methylphosphonate. These solutions are used to evaluate destruction and its efficiency for specific neural agent simulants. The particular removal rates are found to be from 56% up to 96% during 10 min treatment. The data obtained provide basis to evaluate APPJ’s efficiency at different operating conditions. The presented results are promising and could be improved with different operating conditions and optimization of the decontamination process
Effect of genetic and environmental factors on the phenotype characteristics of lambs
The aim of this study was to determine the influence of environmental factors affecting body weight variability of lambs in two crossbreed groups: Pirot x Württemberg and Sjenica x Württemberg. Both populations were managed under the same farm conditions. The data were analyzed to determine the effect of age of the dam, weight of dam, birth type, sex, year and season, on the birth weight and weaning weight of crossbreed lambs. Statistical analysis was performed by GLM procedure using the SPSS statistical package program. The average birth weight of Pirot x Württemberg lambs was 3.56 kg while Sjenica x Württemberg lambs was slightly higher at 3.69 kg. The difference on birth weight between the two crosses was not statistically significant (P>0.05). The average weaning weight of Pirot x Württemberg lambs was 23.54 kg while Sjenica x Württemberg lambs had higher weight at 24.37 kg. The difference of 0.83 kg on weaning weight was statistically significant (P <0.05). Body weight, depending on the environmental factors, ranged from 3.17 to 3.96 kg at birth and from 22.12 to 24.18 kg at weaning in Pirot x Württemberg lambs. Body weight of Sjenica x Württemberg lambs ranged from 3.39 to 3.99 kg at birth and from 22.69 to 25.44 kg at weaning. Statistical analysis showed that the differences were statistically significant (P<0.05) and highly significant (P<0.01)
Dynamics of wet flue gas desulphurization in spray absorber
A concise one dimensional thermal-hydraulic two-fluid model is presented for the numerical prediction of sulphur dioxide absorption from the flue gas onto drops of the water-limestone slurry in the vertical spray tower absorber. The model is based on mass, momentum and energy balance equations for each phase separately, i.e. downward falling droplets of water-limestone slurry and upward flowing flue gas. The sulphur dioxide content in the flue gas is predicted by a balance equation of the sulphur dioxide mass fraction in the flue gas. Interface transfer processes between the flue gas and the droplets are determined by closure laws. The obtained steady-state balance equations are transformed in a form suitable for a direct application of the numerical integration method for the system of ordinary differential equations. The developed thermal-hydraulic model is validated by comparing numerical results with available measured data at the large utility absorber. The presented results clearly show the dynamics of flue gas and droplets thermal-hydraulic processes and their influence on the absorption process
A computer verification of a conjecture about the Erdös-Mordell curve
In this paper we consider Erdös-Mordell inequality and its extension in the plane of triangle to the Erdös-Mordell curve. Algebraic equation of this curve is derived, and using modern computer tools in mathematics, we verified one conjecture that relates to Erdös-Mordell curve