AbstractIn the operation of bioreactors, the fluid movement promotes mixing between sludge and substrate. The dynamics of this system are complex, and the interaction between the phases is difficult to evaluate accurately. In this work, Computational Fluid Dynamics is applied to simulate a pilot-scale anaerobic sequencing batch reactor, using a three-dimensional, transient and multiphase modeling. Several correlations were applied to estimate the interfacial forces. Results indicate that the use of different coefficients for the drag and lift forces strongly affects the predicted turbulent kinetic energy, and thus the mixture estimation in the bioreactor. The use of the drag as the only interfacial force provided an average turbulent kinetic energy close to the value found using a more complete model. However, the absence of lift and virtual mass forces had a significant impact on the resulting turbulence distribution.

This paper discusses the effect of different internal recirculation velocities on the mixture and shear stress on the flocs in an anaerobic sequencing batch reactor (ASBR). Thus, simulations are performed using a computational fluid dynamics (CFD) tool to evaluate this dependency. The analysis of velocities and turbulent kinetic energy indicates that the highest flow evaluated (0.003 m³/s) results in better mixing within the reactor. However, care must be taken with the recycling pipe size, in order to maintain the shear stress inside the range of optimal values.

At the 2nd. Department of Zootechny of the E. S. A. L. Q., in Piracicaba, between 1953 and 1955 an experiment of sugar cane varieties was carried out, with the objective of discovering varieties to substitute "Taquara" (the variety most widely used) and Co 290 (the most recommended). The former was condemned as being too susceptible to cane smut and the latter showes signs if degeneracy. In the experiment, 8 varieties were used with 3 replications in randomized blocks, in 3 rows each. The cane was crop not in the same period, but when they were at comparable ripeness (70 cm of apparent culm). They were crop twice during the year, with a sharp hoe near the soil. The summary of the results and the statistical analyses are shown in tables 1 to 3, showing the possibility of there being 3 groups: A superior one composed of Co 419, a median one, in decreasing order of production, composed of Kassoer, CB 40-69. Co 413, IAC 36-25 and POJ 161 and an inferior group composed of Co 290 and Taquara. There is a possibility that POJ 161 belongs to the last group. Nevertheless, this variety is not recommend because of its susceptibility to smut. As Kassoer is more healthy, vigorous and enduring than Co 419 and other varieties, it is shown recommendable. IAC 36-25 is being recommended presently for forage since its productions is lower than Kassoer, placing 5th productivity, although statistical significance was not detected. As our final conclusions, Co 419, Kassoer, CB 40-69, Co 413 and IAC 36-25 can be planted as forage while POJ 161, Co 290 and Taquara should not. The last two were exactly those used as forage reserve in the 2nd. Department at the beginning of the experiment.

Searching for a substitute of wheat bran and wheat standard middlings in chick mashes, three experiments were carried out using ground sorghums. In the first one, 30% of Atlas, Kafir e White Afrikan x Sumac (seed chops) were substituted for 30% of wheat by-products. All the rations with sorghum grain gave inferior results. In another experiment, 7, 14, 20 and 30% of sorghum substituted equal percentages of those wheat by-products, the best results having been obtained with 7% of Atlas and 23% of wheat by-products. Finally, in a third experiment, 5% of dried cow manure plus 10, 20 and 30% of ground Atlas sorghum were substituted for 5% of alfalfa hay meal plus, respectively, 10, 20 and 30% of wheat by-products. All results obtained from rations containing sorghum were as good as or better than that given by the ration including alfalfa hay meal and only wheat by-products. Under the conditions of this experiment, 5% of cow manure plus 12,25% of sorghum and 17,75% of wheat by-products is supposed to be the best combination to be recommended, this result having been attained through the study of the regression equation.

Three groups of 6 pigs, three months old, were fed the same basal ration of corn and mineral mixture ad libitum. The control group received soybeans oil meal (solvent proc.), the second group raw soybeans and the third one, sprouted soybeans. The feed intake, daily gain and conversion were practically the same in the three groups as the analisis of variance revealed. Conclusion is it does not pay to sprout soybeans for pigs.

Kikuio grass (Pennisetum clandestinum Hochst) is beyond any doubt, a pasture very important for farm animals; since its chemical composition is very similar to that of alfalfa, the present field trial was carried out; a randomized block design with 8 treatments was selected as follows: 1 N - P - K - Ca - Mg (complete manuring) 2 N - P - K - Ca----- (without Mg) 3 N - P - K-------Mg (without Ca) 4 ----P - K - Ca - Mg (without N) 5 N------K - Ca Mg (without P) 6 N - P - Ca - Mg (without K) 7 organic matter (without mineral fertilizers) 8 control Nitrogen was applied as NaN03 (topdressed) and as ammonium sulfate; P2O5 was given as superphosphate associated to bonemeal; K2O was applied as muriate, CaO as "sambaquis" (oyster shells); MgO was given as MgSO4 (topdressed). The source of organic matter was farmyard manure. As far yields are concerned the following observations were made: 1. treatment n. 7 was superior to all others; 2. considering the mineral fertilizers, good responses were due to N and P2O5; 3. the control yield was exceedingly poor, being inferior to all the others treatments; The chemical analyses revealed that: 1. the protein content decreased accordingly to this order: 7, 6, 5 and 1; treatment 4 (without N) gave the lowest protein content; 2. treatment n. 4 produced the highest fat content; treatment no. 7 ranked second; no. 8 gave the lowest fat content; 3. crude fiber: highest - treatment 7; lowest - 8; 4. ashes: the ashes content was higher in treatment 5; proprobably because the most abundant element in the ashes is K, the ash content of treatment 6 (no K) was very low; 5. non nitrogenous substances (determined by difference) - high in treatment 8 and low in treatment 7; 6. mineral elements in the ashes - the element omitted from a given treatment was very low in the grasses therein obtained; this shows the relative poverty of the soil in that element. As general remark the Authors suggest the use of farmyard manure in the fertilization of Kikuio grass; farmyard manure could probably substitute wither green manure or compost.

The AA. have studied, in this paper, the correlation of egg production in yearling R. I. R. pullets and the difference between the pelvic bones, an between the pelvic bones and keel. The distances between those bones were measured by the fingers. It was suggested an index = spread of pelvic x spread of keel bone. These three data were compared with the last 30 days production and with the production to date - six months. Comparisons have been made with 285 pullets. The AA. have concluded: (a) there is a positive correlation between the spread of the pelvic bones and the last 30 days (r = + 0,23 and pr = + 0,16); (b) there is not correlation of the distance between the pelvic bories to the keel and the last 30 days (r = + 0,11 and pr = - 0,01; (c) there is positive correlation of the distance between the pelvic bones to the keel and last six months production (r = + 0,27 and pr = + 0,19); (d) the correlation of the index sugested pratically equals correlation between pelvic bones (r = + 0,27 and pr = + 0,19); (e) correlation between last 30 days production and the total egg production is high (r = + 0,55 and pr = 0,53). Is is stated that spread of the pelvic bones is a low index of actual production and the distance of the keel a low index of total egg production in R. I. R. pullets. The last month real production is a better index of the total egg production.

This paper deals with an experiment to determine the optimum period (number of days) in fattening chickens. Thirty chickens R. I. R. were numbered, weighed and feeded in crate, with one standard ration (17% crude protein). The chickens were weighted every two days and the results obtained indicate the optimum is reached between 12 and 16 days of feeding. It was observed that after 16 days the weights stop or decrease progressively as showed by the Grafic I.

Four years of inbreeding and its effects on fertility, hatchability, viability and egg production in the new bred "PPPP" (Pescoço Pelado Preta Piracicaba) (naked neck and black plumage, Piracicaba) were reported in this paper. It was observed a decrease in fertility, hatchability, viability and egg production as the inbreeding increases. The black plumage naked neck homozygozous chickens are now submitted to a system of uncontrolled mating in the hope that the natural selection will reduce some of the undesirable factors providing abundant material for pedigree control.

The data reported in this paper are in accordance with the hypothesis previously established (2) of the interaction of a main pair of alleles as controlling the inheritance of black, blue and blue-splashed plumage in chickens received from the State of Goias, Brazil. The black plumage is relatively uniform but the blue and blue splashed plumages indicate the action of other genes regulating the lack of uniformity.

This paper deals with the inheritance of black, blue and blue-splashed plumage in poultry. The material analysed had its origin in the State of Goias, Brazil and the genetical data seems to indicate the interaction of a single pair of genes as in the Andalusian fowls and other blue breeds. The dominant gene for blue egg is also present in the material and selection is now being directed to isolate a breed with blue plumage and blue eggs, named "Tudo Azul", what in Portuguese means all blue (plumage and eggs) and corresponds, in braziliian slang, to the expression "O. K." used in the United States. The commercial possibility of the chickens, as judging by its, laying capacity, is emphasized.

The pedigree of chickens homozygous for black plumage and naked and now obtained in the Poultry Department of the "Luiz de Queiroz" School of Agriculture, was traced in this paper. The animals will be used in the formation of the new local breed called "Piracicaba PPPP", (Pescoço Pelado Preta de Piracicaba), which we propose to start with selection of others morphological characters and mainly the economical ones: egg laying, early maturing and soft-meated chickens.

Visando a obtenção dum método fácil e rápido para calcular rações para animais, o Autor deduz e apresenta uma fórmula que dará a quantidade dum alimento a ser acrescentada a uma mistura para balanceá-la. Sugere a necessidade de tabelas apropriadas para facilitar o uso da fórmula.

Looking for a short and quick method for calculating animal ration, the Author deduces and presents a formula which gives the amount of a particular food to be added to the mixture for a balanced diet. The necessity of proper tables to facilitate the use of the formula is pointed out.