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Studies on the growth performance of native chicken ecotypes and RIR chicken under improved management system in northwest Ethiopia النص الكامل
2006
Hassen, H. | Neser, F.W.C. | Dessie, Tadelle | Kock, A. de | Marle-Koster, E. van
A study was conducted to evaluate the growth performance of native and RIR chickens under intensive management condition for 22 weeks using a standard commercial ration. Seven native chicken populations were collected from representative administrative zones in northwest Ethiopia. The experimental layout was a Completely Randomized Design (CRD) with three replications. Data on feed consumption, body weight and related parameters were collected up to the age of 22 weeks. The mean total feed intake for the seven native chicken ecotypes and RIR chicken lines at the end of their growth phase were 13.80, 15.16, 13.44, 13.25, 13.81, 13.36, 14.11 and 12.83 kg for the native chicken types named as Tilili, Gellilia, Debre-Ellias, Mello-Hamusit, Gassay, Guangua, Mecha and RIR, respectively. There was no significant difference in feed consumption among the tested chicken ecotypes. However, a significant (p<0.05) difference was observed in average body weight and body weight gain between the different lines. The average body weights for Tilili , Gellilia, Debre-Ellias, Mello-Hamusit, Gassay, Guangua, Mecha and RIR were 1191, 1186, 1054, 1222, 1038, 1249, 1257 and 1394 g respectively. The lowest and highest mean mature body weight at the age of 22 weeks were 1038 g for Gassay and 1257g for Mecha native chicken lines, respectively. Besides, the average mature body weight for Tilili, Gellilia, Debre-Ellias, Mello-Hamusit, Gassay, Guangua, Mecha and RIR was 1191, 1186, 1054, 1222, 1038, 1249, 1257 and 1394 g and their mean daily body weight growth rates were 7.6, 7.5, 6.7, 7.8, 6.6, 7.9, 8.0 and 8.8 g per bird, respectively. The native chicken lines named as Mello-Hamusit, Guangua and Mecha were the fastest growers among the native chicken lines. Mortality from hatching to end of the growth period i.e. at maturity was higher for all the native and RIR chickens used under intensive management condition.
اظهر المزيد [+] اقل [-]Estimation and comparison of benefits due to feeding hay and silage during the dry season on commercial dual-purpose cattle production systems in Honduras and Costa Rica
2006
Schoonhoven, A.D. | Holmann, F. | Argel, P. | Ordoñez, J.C. | Chaves, J.
Smallholders with dual-purpose cattle production systems in most Central America experience a shortage of forages during the dry season (4-8 month. As a result, substantially lower milk production and weight gain occurs. Dual-purpose operations seeking to maximize milk and beef production in the dry season can produce and feed hay or silage to their livestock. The increase in milk and beef production due to feeding hay or silage during the dry season on commercial dual-purpose cattle productions systems, the production costs of making silage or hay and the benefits as a result of feeding silage or hay are estimated and compared in Honduras and Costa Rica. Due to feeding silage or hay, farmers in Honduras and Costa Rica have increased milk production during the dry season. The costs of feeding hay are lower in both countries, although farmers feed a higher amount (kg DM/cow/ day) than silage. Feeding silage or hay to milking cows is profitable in both countries. The income-cost ratio and the net benefit ($/ cow/day) due to feeding these feedstuffs are positive. Farmers with milking cows in Honduras realise a higher income-cost ratio and net benefit due to feeding silage and hay than farmers in Costa Rica. Likewise, beef cows or young livestock supplemented with these feeding alternatives don't loose weight during the dry season. In Honduras as well in Costa Rica, it is profitable to feed silage or hay to beef cows or young livestock. Currently, no silage and a small hay market exist in Honduras. Possibly, these will develop due to an increasing demand for these profitable feedstuffs. In Costa Rica thanks to the efforts of agricultural organisations, a hay market of different qualities is developing.
اظهر المزيد [+] اقل [-]Estimation and comparison of benefits due to feeding hay and silage during the dry season on commercial dual-purpose cattle production systems in Honduras and Costa Rica النص الكامل
2006
Schoonhoven, Aart van | Holmann, Federico J. | Argel M., Pedro J. | Pérez, E. | Ordoñez, J.C. | Chaves, J.
Smallholders with dual-purpose cattle production systems in most Central America experience a shortage of forages during the dry season (4-8 month. As a result, substantially lower milk production and weight gain occurs. Dual-purpose operations seeking to maximize milk and beef production in the dry season can produce and feed hay or silage to their livestock. The increase in milk and beef production due to feeding hay or silage during the dry season on commercial dual-purpose cattle productions systems, the production costs of making silage or hay and the benefits as a result of feeding silage or hay are estimated and compared in Honduras and Costa Rica. Due to feeding silage or hay, farmers in Honduras and Costa Rica have increased milk production during the dry season. The costs of feeding hay are lower in both countries, although farmers feed a higher amount (kg DM/cow/day) than silage. Feeding silage or hay to milking cows is profitable in both countries. The income-cost ratio and the net benefit ($/cow/day) due to feeding these feedstuffs are positive. Farmers with milking cows in Honduras realise a higher income-cost ratio and net benefit due to feeding silage and hay than farmers in Costa Rica. Likewise, beef cows or young livestock supplemented with these feeding alternatives don't loose weight during the dry season. In Honduras as well in Costa Rica, it is profitable to feed silage or hay to beef cows or young livestock. Currently, no silage and a small hay market exist in Honduras. Possibly, these will develop due to an increasing demand for these profitable feedstuffs. In Costa Rica thanks to the efforts of agricultural organisations, a hay market of different qualities is developing.
اظهر المزيد [+] اقل [-]Estimation and comparison of benefits due to feeding hay and silage during the dry season on commercial dual-purpose cattle production systems in Honduras and Costa Rica
2006
Schoonhoven, A.D. | Holmann, F. | Argel, P. | Ordoñez, J.C. | Chaves, J.
Smallholders with dual-purpose cattle production systems in most Central America experience a shortage of forages during the dry season (4-8 month. As a result, substantially lower milk production and weight gain occurs. Dual-purpose operations seeking to maximize milk and beef production in the dry season can produce and feed hay or silage to their livestock. The increase in milk and beef production due to feeding hay or silage during the dry season on commercial dual-purpose cattle productions systems, the production costs of making silage or hay and the benefits as a result of feeding silage or hay are estimated and compared in Honduras and Costa Rica. Due to feeding silage or hay, farmers in Honduras and Costa Rica have increased milk production during the dry season. The costs of feeding hay are lower in both countries, although farmers feed a higher amount (kg DM/cow/ day) than silage. Feeding silage or hay to milking cows is profitable in both countries. The income-cost ratio and the net benefit ($/ cow/day) due to feeding these feedstuffs are positive. Farmers with milking cows in Honduras realise a higher income-cost ratio and net benefit due to feeding silage and hay than farmers in Costa Rica. Likewise, beef cows or young livestock supplemented with these feeding alternatives don't loose weight during the dry season. In Honduras as well in Costa Rica, it is profitable to feed silage or hay to beef cows or young livestock. Currently, no silage and a small hay market exist in Honduras. Possibly, these will develop due to an increasing demand for these profitable feedstuffs. In Costa Rica thanks to the efforts of agricultural organisations, a hay market of different qualities is developing.
اظهر المزيد [+] اقل [-]Herbs additive projection on pigs growth intensity and digestive tract microflora
2006
Jansons, I. | Nudiens, J.
A study was conducted to determine efficiency of a phytoadditive on pig growth processes and digestive tract microflora. The pigs of control group were fed without the phytoadditive. The feed of the trial group piglets contained 0.5% of the phytoadditive per tonne feed, for starter pigs and finished pigs - 0.2% per tonne feed. The study indicated that at the age of 170 days, pig mass in the trial group was 111.67+-1.22 kg on average, but in the control group - 101.79+-0.81 kg, which showed that pigs from the trial group had by 9.7% higher average mass than in the control group (p is less than 0.05). Average daily gain for the trial group was 0.777+-0.009 kg, which was by 12 % more than for the control group pigs (p is less than 0.05). Feed conversion in the trial group was 2.928 kg, but in the control group - 3.129 kg, which was by 6.4% higher than in the trial group. Gastric microflora analyses showed that use of phytoadditive reduced mould colony forming units (CFU) amount in the trial group decreased by 24 times. Duodenum microflora analyses showed that use of phytoadditive reduced mould CFU amount by 25%, yeast CFU amount by 34%, Escherichia coli mesophilic and termophilic forms CFU by 16.3% compared to the control. A lactic acid bacterium CFU in the trial group was 2.5 times higher compared to the control. Rectum microflora analyses showed that use of phytoadditive reduced mould CFU amount by 31.6%, yeast CFU amount - by 62%, Escherichia coli mesophilic and termophilic forms by 57 % and 15.6 % respectively. Lactic acid bacteria CFU amount in 1 g of sample in the trial group increased by 5.1 times.
اظهر المزيد [+] اقل [-]Stress modelling of chopped biomass
2006
Nulle, I. | Kakitis, A.
Relevant resources for renewable biomass fuel production are wood, cereal straw residues, and emergent vegetation from wetlands. Peat is an important slowly renewable biomass fuel too. Using blended peat and woody or herbaceous biomass, sulphur content of the fuels is increased and, if the mixture is burned, sulphates are formed instead of chlorides, and the risk of high temperature corrosion is avoided. The loading, storage container discharging, mixing and automatic feeding process depends on internal stresses acting in the biomass volume. To estimate vertical stress in silos, a mathematical model was built. Vertical stress in the opening of the silo hopper reaches 1.4 kPa if the diameter of a silo is 0.4 m, but for the diameter of 2 m it is possible to obtain even 7.2 kPa. Increase of the coefficients lambda and mu to the maximal values (lambda = 0.6; mu = 0.5) decreases vertical stress for more than 70%.
اظهر المزيد [+] اقل [-]Pollution of water and sludge with heavy metals and oil products in park pond of Kedainiai town
2006
Sukys, P.
The paper presents the analysis of the pollution of water and sludge of the pond situated in the park of Kedainiai town. The analysis of pollutants such as heavy metals and oil-products has been carried out with the aim to evaluate the possibilities of arranging a sanitary safe bathing, place in the park and use the accumulated sludge. It was determined that the content of heavy metals in sludge exceeds the maximum permissible limit for sludge pollution in Lithuania. According to cadmium amount, the pollution also exceeds maximum allowable soil pollution level. However, the sludge in the pond contains a rather large amount of oil-products. After carrying out stirring-up tests of bottom sludge, it was determined that turbid water is polluted with oil-products that exceed the maximum permissible limit.
اظهر المزيد [+] اقل [-]Investigation of ground water and water from shallow wells located in karst zone
2006
Rudzianskaite, A.
The paper discusses the peculiarities of hydrological and hydro-chemical regime of ground water in shallow wells and boreholes in moraine soils of active karts zone. It was determined that the fluctuations in water levels in boreholes and wells have the same tendencies: water was closest to the ground surface when the air temperature was increasing in the cold period (November-March) and decreasing in the warm period (April-October) pf the year. Chemical composition of water in boreholes (sum of ions) was up to 1.2 times lower than that in well water. This was determined by higher sodium, sulphates, and chlorine and nitrates amounts. When water level is decreasing, water chemical composition is increasing in water of wells and boreholes. It was determined that water in wells was contaminated with nitrate nitrogen; water in boreholes was polluted with ammonia nitrogen.
اظهر المزيد [+] اقل [-]Investigations of the pollution of surface (rain) wastewater and its impact on the environment
2006
Steponavicius, A.
The paper presents the analysis of legal acts and normative documents regulating the management of surface (rain) wastewater in Lithuania. On the basis of the results, the investigations on treatment efficiency of pollution of surface wastewater accumulated in the territory of the cattle and pigs slaughterhouse of Krekenavos mesa Ltd were carried out. Having applied differentiated runoff coefficients calculations of the dependence of wastewater amount territory of the company were suggested. According to the monitoring program, wastewater pollution indices and investigation frequency were determined in respect of the requirements of surface water monitoring. Wastewater pollution dynamics in treatment facilities of the company was estimated. As it was determined, the main index specifying treatment necessity of subsurface wastewater accumulated in company's territory is suspended solids. Considering this index it was determined that maximum wastewater pollution exceeded the determined rate of environmental requirements 2.13 times within the study period. After treatment in the facilities, the average wastewater pollution with suspended solids decreased from 31.44 mg lE-1 to 8.67 mg lE-1. Other pollutants concentrations contained in wastewater were insignificant and did not exceed the rate determined in the environmental requirements, thus they may be released into open water bodies. It was also determined that the average amount of suspended solids contained in the Upyte stream reached 17.55 mg lE-1. Considering this index, pollution of wastewater outlet is 50.6% lower than the background pollution of the stream.
اظهر المزيد [+] اقل [-]Treatment of wastewater in milk collecting station
2006
Askinis, S.
The paper presents the test results of studies on the treatment of wastewater in experimental treatment facilities in a milk collecting station. The treatment process of wastewater was a follows: aeration-flocculation device -sedimentation pond - two-stage constructed wetlands. The laboratory investigations have shown that the primary treatment with quicklime (1 kg mE-3) reduces wastewater pollution by 54%, while the treatment with coagulant 'ZETAG 8660' (4 g mE-3) reduces it by even 68%. Such results were not obtained in the primary wastewater treatment stage under industrial conditions: biological oxygen demand (BOD5) in wastewater was reduced 27.2%, the amount of suspended sediment was reduced by 48.1%, the amounts of Ntotal and Ptotal decreased by 15.8% and 27% respectively. Such results much depended on the air temperature, inaccurate dosage of chemicals as well as on insufficient capacity of reaction and sedimentation reservoirs for 2.5 times higher amount of wastewater. However, despite such unfavourable conditions, this stage of treatment process was rather efficient: the pollution of wastewater with organic matter flowing into the stream did not exceed the maximum allowable rates. The average value according to BOD5 was 4 mg O2 lE-1, the highest BOD5 value was 9.6 mg O2 lE-1. From the environment protection point of view, it is particularly important that the removal of biogenic pollutants is quite sufficient in the wastewater treatment facilities. After the treatment process in wastewater treatment facilities, the amount of Ntotal decreased by 82.4% and the amount of Ptotal was reduced by even 97.3%.
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