No abstract

Indian River broiler breeder hens (n = 29) were caged individually to investigate whether hen age and egg sequence position were related significantly to the dependent variables fertility, hatchability, viability (hatch of fertile eggs), and preincubation embryonic development. Hens were artificially inseminated once per week. All eggs laid during the period of 31 to 54 wk of age were stored at 16 to 17 C for .5 to 7 days. Time of oviposition records were used to assign eggs to sequence position ("first" or "subsequent"). Eggs laid on odd-numbered weeks were broken open, fertility determined, and embryonic development staged. Eggs laid on even-numbered weeks were sent to a commercial hatchery to assess hatchability. Unhatched eggs were opened to determine fertility and embryonic mortality. In addition, hen weight, number of days since insemination, time of oviposition, and egg weight were recorded to determine their relationship to the dependent variables. Fertility (n = 3,240 eggs) and hatchability (n = 1,653 eggs) were not significantly related to egg sequence position, but were related to hen age (P = .0001 and P = .0002, respectively). Older hens demonstrated lower fertility and hatchability. In contrast, embryo viability (n = 1,487 eggs) and preincubation embryonic development (n = 1,200 eggs) were not significantly related to hen age, but were related to egg sequence position (P = .0026 and P = .0001, respectively). First-of-sequence eggs had lower viability, and embryos of these eggs were more developed than embryos of subsequent eggs. These data indicate that the reduction in chick production observed as the hen ages may be due to the increased incidence of first-of-sequence eggs.

Key impediments to increased corn yield and quality in the southeastern US coastal plain region are damage by ear-feeding insects and aflatoxin contamination caused by infection of Aspergillus flavus. Key ear-feeding insects are corn earworm, Helicoverpa zea, fall armyworm, Spodoptera frugiperda, maize weevil, Sitophilus zeamais, and brown stink bug, Euschistus servus. In 2006 and 2007, aflatoxin contamination and insect damage were sampled before harvest in three 0.4-hectare corn fields using a grid sampling method. The feeding damage by each of ear/kernel-feeding insects (i.e., corn earworm/fall armyworm damage on the silk/cob, and discoloration of corn kernels by stink bugs), and maize weevil population were assessed at each grid point with five ears. The spatial distribution pattern of aflatoxin contamination was also assessed using the corn samples collected at each sampling point. Aflatoxin level was correlated to the number of maize weevils and stink bug-discolored kernels, but not closely correlated to either husk coverage or corn earworm damage. Contour maps of the maize weevil populations, stink bug-damaged kernels, and aflatoxin levels exhibited an aggregated distribution pattern with a strong edge effect on all three parameters. The separation of silk- and cob-feeding insects from kernel-feeding insects, as well as chewing (i.e., the corn earworm and maize weevil) and piercing-sucking insects (i.e., the stink bugs) and their damage in relation to aflatoxin accumulation is economically important. Both theoretic and applied ramifications of this study were discussed by proposing a hypothesis on the underlying mechanisms of the aggregated distribution patterns and strong edge effect of insect damage and aflatoxin contamination, and by discussing possible management tactics for aflatoxin reduction by proper management of kernel-feeding insects. Future directions on basic and applied research related to aflatoxin contamination are also discussed.

Four pearl millet genotypes were tested for their potential as raw material for fuel ethanol production in this study. Ethanol fermentation was performed both in flasks on a rotary shaker and in a 5-L bioreactor using Saccharoinyces cerei'isiae (ATCC 24860). For rotary-shaker fermentation, the final ethanol yields were 8.7-16.8% (v/v) at dry mass concentrations of 20-35%, and the ethanol fermentation efficiencies were 90.0-95.6%. Ethanol fermentation efficiency at 30% dry mass on a 5-L bioreactor reached 94.2%, which was greater than that from fermentation Since the late 1970s, fuel ethanol production from renewable resources has grown into a huge industry and provides several billion gallons of ethanol for formulated gasoline in Canada, Brazil, the United States, and some other countries (Wheals et al 1999). The annual production of ethanol in the United States was 3.4 billion gallons in 2004 and is expected to reach 5.5 billion gallons by year 2005. About 30% of the gasoline in the United States currently is blended with ethanol and the percentage is still growing (MacDonald et al 2003). This makes the fuel ethanol industry the fastest growing energy industry in the world. A great amount of research has been conducted on corn to achieve higher ethanol yields or to increase values of the byproducts. Seed companies have made a great effort to develop corn hybrids with higher starch contents or higher extractable starch contents to increase ethanol yields (Bothast and Schlicher 2005). Utilizing both starch and fiber in the grains and increasing starch loading are also the major focus to achieve high ethanol yields. Bruce et al (2004) reported that a modified corn dry-grind process using both starch and fiber can increase ethanol yield by 7%. Ponnampalam et al (2004) reported that the integration of germ and fiber removal in the dry-grind ethanol industry could raise fermentation capacity, add value to by-products, and increase ethanol yield by 11%. Corn is an excellent source of starch for a glucose platform. However, corn alone can not meet the demand for fuel ethanol. The United States consumes more than 150 billion gallons of fuel for automobiles per year (Hicks et al 2005). Even if 100% of the 2004 corn crop were used for ethanol production, the produced ethanol would have only met 23% of our demands. Obviously, other small grains are needed for ethanol production, especially in areas without corn. Although the biological process for ethanol production is the same in all the distilleries (conversion of glucose to ethanol), the major raw materials used in ethanol plants at different locations may be quite different. The price and availability of the raw materials and the price of by-products are critical factors for ethanol plants to maintain profitability. Sugarcane juice and molasses are the dominant materials for ethanol production in Brazil. In the United States and Canada. fuel ethanol is produced primarily from Contribution No. 05-297-i from the Kansas Agricultural Experiment Station. Manhattan, KS 66506.

No abstract

Brown stink bug, Euschistus servus (Say) (Heteroptera: Pentatomidae), damage on developing corn, Zea mays L., ears was examined in 2005 and 2006 by using eight parameters related to its yield and kernel quality. Stink bug infestations were initiated when the corn plants were at tasseling (VT), mid-silking (R1), and blister (R2) stages by using zero, three, and six in 2005 or zero, one, two, and four bugs per ear in 2006, and maintained for 9 d. The percentage of discolored kernels was affected by stink bug number in both years, but not always affected by plant growth stage. The growth stage effect on the percentage of discolored kernels was significant in 2006, but not in 2005. The percentage of aborted kernels was affected by both stink bug number and plant growth stage in 2005 but not in 2006. Kernel weight was significantly reduced when three E. sercus adults were confined on a corn ear at stage VT or R1 for 9 d in 2005, whereas one or two adults per ear resulted in no kernel weight loss, but four E. servus adults did cause significant kernel weight loss at stage VT in 2006. Stink bug feeding injury at stage R2 did not affect kernel damage, ear weight or grain weight in either year. The infestation duration (9 or 18 d) was positively correlated to the percentage of discolored kernels but did not affect kernel or ear weight. Based on the regression equations between the kernel weight and stink bug number, the gain threshold or economic injury level should be 0.5 bugs per ear for 9 d at stage VT and less for stage R1. This information will be useful in developing management guidelines for stink bugs in field corn during ear formation and early grain filling stages.

Broiler breeder hens are typically provided a restricted amount of feed once a day. This feed is rapidly consumed; therefore, the hens fast for an extended period of time before their next feeding. In the current research, the effects on reproductive performance of implementing a twice-a-day vs. a once-a-day feeding program after photostimulation were investigated. Pullets and cockerels were reared on a skip-a-day feeding program. Pullets were weighed at 20 wk of age and then distributed into 30 laying pens such that each pen had a similar BW distribution. Each individual laying pen consisted of 35 hens and 4 roosters. At 21 wk of age, the birds were photostimulated for reproduction and 15 of the laying pens were placed on a once-a-day feeding schedule, whereas the other 15 pens were placed on a twice-a-day feeding schedule. The total amount of feed provided per day to all the laying pens was the same. Birds fed once a day received all their feed at 0630 h, whereas birds fed twice a day received 60% of their total feed allotment at 0630 h and the other 40% at 1500 h. Even though both treatment groups began egg production at the end of wk 23, birds fed twice a day laid more (P < or = 0.05) eggs through 42 wk of age than those fed once a day. Additionally, the average egg weight for the entire production period, which lasted until the birds were 60 wk of age, was greater for hens fed twice a day. Overall BW uniformity for the entire experiment was significantly better for hens fed twice a day vs. once a day. However, cumulative mortality was significantly higher for hens fed twice a day than for those fed once a day. The results indicate that feeding broiler breeder hens twice a day after photostimulation may enhance reproductive performance during the early lay period.

Egg fragments, paper pads from chick boxes, and fluff samples were obtained from six commercial broiler breeder hatcheries and analyzed for the presence and level of salmonellae. Overall, 42 of 380 samples (11.1%) from those hatcheries were contaminated with salmonellae. Salmonellae organisms were detected in 22 of 145 (15.2%), 5 of 100 (4.6%), and 15 of 125 (12%) samples of egg fragments, fluff, and paper pads, respectively. The percentage salmonellae-positive samples from each of the six hatcheries were 1.3, 5.0, 22.5, 11.4, 36.0, and 4.3% respectively. Of the 140 samples randomly selected for enumeration, salmonellae were found in 11 samples. Four of these 11 samples had greater than 10(3) salmonellae per sample, 3 others had greater than 10(2) but less than 10(3), and the remaining 4 had less than 10(2). Salmonella serotypes isolated were S. berta, S. california, S. give, S. hadar, S. mbandaka, S. senftenberg, and S. typhimurium, all of which have previously been isolated from poultry. The incidence and extent of salmonellae-positive samples found in the breeder hatcheries were much less than that previously found in broiler hatcheries. Many factors contribute to the lower incidence and level of salmonellae found in the breeder hatcheries; however both the breeder and broiler hatcheries present critical control points in the prevention of salmonellae contamination during commercial poultry production. The cycle of salmonellae contamination will not likely be broken until contamination at these critical points is eliminated.