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.

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.

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.

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.

Fuel as the main energy resource in agriculture and forest production is surveyed in the work. Specific weight of fuel and lubricants in applicable expenses in country farms is analysed, average fuel and oil consumption in farms of different specialization, as well as changes in oil price in farms of different size and specialization are shown.

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%.

The paper presents the investigations performed by Water Management Institute of Lithuania University of Agriculture on the pollution and treatment efficiency of wastewater formed in an up-to-date slaughterhouse built in 2003. Wastewater is canalized from the slaughterhouse by red and green sewerage systems. Initially the wastewater is pre-treated in a fat separator, further treatment process is performed in physical-chemical treatment facilities and settling ponds. After primary treatment, the wastewater is directed into two-stage constructed wetlands of horizontal flow. The wastewater in slaughterhouse is about 4-5 times more polluted than domestic wastewater containing even 20 times higher for concentration. During the primary treatment process (fat separator + physical-chemical treatment device + settling pond), from 73.1 to 98.9% of pollutants are removed. After primary treatment, indices of wastewater are similar to those of domestic wastewater: pH - 8.5, biochemical oxygen demand (BOD5) - 98 mg lE-1 of O2, Ntotal and Ptotal - 46 and 8.9 mg lE-1 respectively. After biological treatment in two-stage constructed wetlands of horizontal flow, the wastewater satisfies the environmental protection requirements according to organic (BOD5) and biogenic (Ntotal and Ptotal) pollutants and thus may be realised into the environment. Regression dependencies of medium and strong relation (R**2=0.503-0.893) of pollutants BOd5, SS (suspended sediments), Ntotal and Ptotal in treated wastewater on the total of constructed wetlands have been determined.

In the process of biological wastewater treatment, P-removal is efficient enough when the concentration of organic pollutants according to BOD5 (biochemical oxygen demand) is no higher than 190 mg lE-1 of O2 and its relationship with phosphorus does not exceed 20. Having studied the composition of wastewater from dairy farms it was determined that wastewater pollution according to BOD5 is from 800 to 900 mg lE-1 of O2 and the ratio of BOD5/Ptotal is 30-36. The paper gives the results of the tests on P-removal from wastewater carried out in a laboratory model. During investigations wastewater was flowing via mineral filters (filtralite P (FLP), zeolite (CE), and shulgite (SG)). Total amount of Ca, Fe and Al oxides contained in those filters were 23.0, 16.1 and 7.9% respectively. The rates of P-removal from wastewater in the filters were as follows: 88.5% (FLP), 45.5% (CE), and 96.3% (SG). Considering different hydraulic load, P-mass balance was calculated. The calculation results showed the following P absorption amounts: FLP - 5.08 g dE-1, CE - 1.76 g dE-1, and SG - 3.91 g dE-1 (calculated for 1 m**3 of each filter). Wastewater filtration through mineral media resulted in the removal of other pollutants, too: organic pollutants removal (according to BOD5) was 30.8 to 72.5%, and the removal of nitrogen compounds (more than 90% of which were in the form of ammonium salts) was even 93.2% in CE filter.

In the paper there are described problems of sewerage system in Riga which essentially impede its normal functioning. There are analyzed operation regimes of two principal pumping stations which pump all wastewater of Riga to the purification plants (2001-2005). The main focus is on implementing different measures that would improve collection and pumping of wastewater. It is offered to build a third penstock from the Voleru chamber to the purification plants. It is suggested to separate the rainwater from the household wastewater. There are analyzed 11 different versions of pump operation. In the conclusions and recommendations the formation of the possible dangerous situation during heavy downpours is demonstrated. It is recommended to build a regulation reservoir near the purification plants which could essentially protect the Daugava from unpurified wastewater during the downpours.