No abstract

well. Recent studies demonstrated that about 2.5 million cubic tons of dried tea is manufactured annually, of this total, approximately 20% is consumed in Asian countries including China, Korea and Japan. Some studies have been performed with animal models, mostly with rodents, to get a better understanding of the effects of green tea components on living organisms (Yang and Wang, 1993;Dreosti et al., 1997). Current studies informed that green tea and catechins, the main components of green tea, have many physiological and biochemical functions including antioxidant and antimutagenic effects (Yen and Chen, 1995;Kuroda and Tomita, 1999). Grimble (1998) reported that green tea had effects to reduce the serum and liver cholesterol levels in the rat. Yamane et al. (1999) reported that green tea extracts included in the diet improved egg quality profiles in a short-term experiment. Also in a longterm feeding study of green tea powder for laying hens had favorable effects on egg quality traits such as thick albumen stability without adverse effect on laying performance (Biswas et al., 2000). Therefore, the objective of this study was to evaluate the effects of green tea powder on laying performance and egg composition of layers as a reference to recommend the optimum dietary level of green tea powder for egg-laying hens.

Soybean [Glycine max (L.) Merr.] is the number one oil and protein crop in the United States, but the seed contains several anti-nutritional factors that are toxic to both humans and livestock. RNA interference technology has become an increasingly popular technique in gene silencing because it allows for both temporal and spatial targeting of specific genes. The objective of this research is to use RNA-mediated gene silencing to down-regulate the soybean gene raffinose synthase 2 (RS2), to reduce total raffinose content in mature seed. Raffinose is a trisaccharide that is indigestible to humans and monogastric animals, and as monogastric animals are the largest consumers of soy products, reducing raffinose would improve the nutritional quality of soybean. An RNAi construct targeting RS2 was designed, cloned, and transformed to the soybean genome via Agrobacterium-mediated transformation. Resulting plants were analyzed for the presence and number of copies of the transgene by PCR and Southern blot. The efficiency of mRNA silencing was confirmed by real-time quantitative PCR. Total raffinose content was determined by HPLC analysis. Transgenic plant lines were recovered that exhibited dramatically reduced levels of raffinose in mature seed, and these lines were further analyzed for other phenotypes such as development and yield. Additionally, a precision-fed rooster assay was conducted to measure the true metabolizable energy (TME) in full-fat soybean meal made from the wild-type or transgenic low-raffinose soybean lines. Transgenic low-raffinose soy had a measured TME of 2,703 kcal/kg, an increase as compared with 2,411 kcal/kg for wild-type. As low digestible energy is a major limiting factor in the percent of soybean meal that can be used in poultry diets, these results may substantiate the use of higher concentrations of low-raffinose, full-fat soy in formulated livestock diets.

Apparent digestibility of dry matter and energy, and availability of amino acids from blood meal (BM), fish meal (FM), meat and bone meal (MBM), poultry byproduct meal (PBM), soybean meal (SBM), corn, wheat and yellow grease (YG) were determined for bluegill Lepomis macrochirus (mean weight, 57 g), and likewise, but not for BM or wheat, for largemouth bass Micropterus salmoides (mean weight, 30 g). To avoid nutrient interaction from a reference diet, diets containing 98.5% (985 g kg )1 ) of test ingredients were used, except for semisolid, YG which was mixed with corn to permit pelletization. Faeces were collected by a siphoning method. Apparent dry matter digestibility values ranged from 50% (corn) to 87% (BM) for bluegill and from 53% (MBM) to 76% (PBM) for largemouth bass. Apparent energy digestibility values ranged from 53% (corn) to 92% (BM) for bluegill and from 63% (MBM) to 93% (YG) for largemouth bass. Apparent digestibility of most amino acids exceeded 90% for evaluated protein sources, except for MBM which showed slightly lower values (80-90%) for both fishes. Isoleucine digestibility from BM was relatively low (82%) for bluegill. High digestibility values for SBM, PBM and BM, indicate good potential for replacing FM in diets for both fishes. KEY WORDS

A 42 day feeding trial involving twenty five, seven weeks old male grass cutters with an initial weight of 604.9-609.7g was conducted to determine the growth response and carcass characteristics of weaner grass cutters fed diets supplemented with P. longifolia seed oil as a natural growth promoter. Five diets were formulated to contain basal diet + 0% P.longifolia oil and Oxytetracycline for T1 this served as negative control while T2 was fed basal diet containing Oxyteteracycline (synthetic growth promoter) as positive control at 25mg/kg, T3, T4 and T5 were fed basal diet supplemented with P. longifolia oil as natural growth promoter at 0.2%, 0.3% and 0.4% respectively. The grass cutters were randomly divided into five groups of five grass cutters each with each grass cutters serving as replicate in a completely randomized design experiment. Feed and clean water were provided ad libitum. There was a significant (P<0.05) differences among the treatments for final live weight, feed conversion ratio, carcass weight and dressing percentage. There was no significant differences (P>0.05) in mortality, feed intake, daily water intake, feed cost per kg and relative weights of the organs examined (liver, kidney, heart, spleen, testis, intestine and abdominal fat). The result of this study indicates that the inclusion of P. longifolia oil up to 0.40% has no deleterious effect on the performance and health status of grass cutters.