Heterosis in Fayoumi strain incrossing
Summary Many experiments have proved the superiority of hybrids resulting from incrossing of mbred lines, which have been utilized commercially in poultry production. The aim oi this experiment was to study the effect of incrossing inbred lines of Fayoumi chickens upon their combinability. The results can be summarized as follows: The fertility percentage 96.7 in comparing with 92.9 (L2j while reached in The heavier incross Lz5 X L3!.j had body weight equal to 118, II2 and io3 % in relation to the control at 4, 8 and i6 weeks of age, respectively. Heterosis in body weight became less obvious as chicks advanced in age and alleles responsible for early growth rate showed a great response to incrossbreeding. Incrossbreeding improved feed utilization of Fayoumi chicks. These results show the possibility for improving the native breed by incrossing and detecting the most efficient incrossbreds.
Estimation of general and specific combining abilities from a diallel cross of three inbred lines of Fayoumi chicks
Three inbred lines of Fayoacmi chicks were incrossed in diallel mating system to estimate general and specific combining ability. The inbreeding coefficients in three inbred lines were 25 , 37 .5 and 5o per cent. L 25 showed the highest g.c.a. in fertility and body weight at 8 weeks of age. L 37 ,5 exhibited the best g.c.a. in viability, while L 50 gave the best g.c.a. in hatchability. The inbreeding coefficient of sire had a highly significant effect on both fertility and hatchability while its effect on viability and body weight at 8 weeks of age was not significant. L z5 X L 37 ,5 incrossbred chicks gave the best s.c.a. in viability and body weight, fertility and hatchability.
Instrumentation and Automated Photometric Titration Procedure for Total Acidity Determination in Red Wine Employing a Multicommuted Flow System
An automated procedure for photometric titration of red wine and associated instrumentation is described. The procedure was based on the flow-batch approach implemented employing multicommutation. The photometric detection was carried out using a homemade LED-based photometer. The mixing device, LED, and photodetector were attached to the titration chamber in order to form a compact and small-sized unit. The flow system comprised an automatic injector and three-way solenoid valves, which were controlled by a microcomputer through an electronic interface card. The software, written in Quick BASIC 4.5, was designed with abilities to accomplish all steps of the titration procedure including data acquisition and real-time processing to decide about the course of titration in the following step and so forth, until the titration endpoint was reached. The usefulness of the proposed titration system was demonstrated by analyzing red wine samples. When results were compared with those obtained using the AOAC reference method, no significant difference was observed at the 95% confidence level. A relative standard deviation of ca  2% (n=9 ) was obtained when processing a typical red wine sample containing 7.3 gl -1 total acidity expressed as tartaric acid.