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SUMMARY The inner perivitelline layer (IPL) sperm hole assay provides an objective assessment of the number of sperm penetrating the hen’s ovum at the germinal disc. That number will provide insight into numerous parameters concerning fertility, including, but not limited to, the probability of the ovum being fertilized (true fertility), the duration of fertility, an assessment of mating activity, the effect of inseminating in vitro-stored semen, and the influence of spiking a breeder flock. In the current paper, we discuss the use of a filter paper ring to isolate and process the IPL overlying the germinal disc (PL disc) in 5 species of domestic birds. The morphology of the PL disc is also described to assist those using the sperm hole assay during sperm hole counting. The filter ring approach was successfully used with chicken, turkey, duck, goose, and Japanese quail eggs; the PL discs remained intact and stretched across the filter ring and sperm holes, when present, were clearly discernible. Morphologically, the PL disc appeared to be a silhouette of the germinal disc, including the germinal vesicle observed in follicular oocytes. The fibers forming the IPL had a honeycomb-like arrangement that could be mistaken for actual sperm holes in faintly stained slides. Given its diversity of applications and relative simplicity using the filter ring, it is recommended that the sperm hole assay be part of a quality control program at the hatchery. Already used in the scientific community, this filter ring method has the additional advantage that the blastoderm may be collected before the staining process.

SUMMARY Campylobacter is a human food-borne pathogen frequently associated with poultry and poultry products and can be found in high numbers within the gut contents of colonized broilers. The number of Campylobacter on broiler carcasses increases markedly during automated defeathering as rubber picker fingers press on the abdomen and can force gut contents out of the cloaca. One method to prevent this increase is to plug the cloaca and prevent escape of gut contents. For a plug to be effective, it must resist expulsion during picking. In the current work, we test shredded sponge or paper as a means to plug broiler carcass cloacae during automated feather removal. Broiler carcass cloacae were plugged before scalding and carcasses were sampled to determine the bacterial numbers present on breast skin after scalding (before feather picking) and again after feather picking. Neither 50 cc of shredded paper nor 25 cc of shredded sponge was effective as a cloacal plug. However, a plug made of 50 cc shredded sponge material was effective to occlude broiler carcass vents during automated defeathering. Significantly fewer Campylobacter cells were detected on the breast skin of post pick carcasses plugged with 50 mL of shredded sponge than on post pick unplugged control carcasses.

Coccidiosis continues to affect caged layers worldwide despite keeping them on wire all their productive lives. Coccidiosis in caged layers, diagnosed either in clinical or subclinical forms, has one feature in common, unpredictability. Until recently, despite the use of vaccine, coccidiosis remained problematic, particularly at the beginning of lay, likely related to the low protective immunity for a lack of vehicle for recycling. An approach for using paper plates, both for vaccination as well as recycling is described. Caged layers that were vaccinated once with gel-puck coccidiosis vaccine laid at over 90% continuously for over 24 wk with little or no problem of coccidiosis.

Summary This study aimed to investigate the effects of modified-dietary fiber from cassava pulp (M-DFCP), mostly classified as insoluble dietary fiber (IDF), as a feed supplement on productive performance, nutrient digestibility, weight of digestive organs, abdominal fat storage, and cholesterol in meat and blood of broiler chickens. A total of 336 one-day-old male broiler chickens (Ross 308) were allocated to 4 groups in 7 replicate pens with 12 chicks each, based on a completely randomized design. Four dietary treatments composed of control and 3 M-DFCP inclusion levels: 0.5, 1.0, and 1.5%. The results showed that M-DFCP showed no negative effects on growth performance in broiler chickens. The inclusion of M-DFCP in diets at 1.0 to 1.5% had positive effects on increased gizzard weight, reduced gizzard pH, and reduced abdominal fat. The M-DFCP at 1.0% can also increase nutrient digestibility (dry matter, organic matter, and ether extract). In addition, the supplementation of M-DFCP at 1.0 to 1.5% in diets represented lower cholesterol in serum, breast and thigh meats, and liver of broiler chickens. In conclusion, these results indicate that M-DFCP can be used as an IDF source in broiler diets. The inclusion of 1.0% M-DFCP in broiler diet has positive effects on enhancing gizzard function, improving nutrient digestibility, and reducing abdominal fat and cholesterol in chicken meat, blood, and liver.

SUMMARY Because of fecal shedding from Campylobacter-positive birds, broiler transport cages can be contaminated with Campylobacter, leading to cross-contamination of previously Campylobacter-negative broilers during live haul. Earlier work has shown that drying soiled or washed cages for 24 to 48 h can lower or even eliminate detectable Campylobacter on cage flooring. Because extended drying times are impractical, we tested the use of hot flowing air to speed the process. To determine if the effect was due to heat alone or flowing air alone, hot flowing air was compared with unheated flowing air and static hot air as well as with a benchtop control. The numbers of Campylobacter, Escherichia coli, and coliforms on small squares of washed or unwashed fecally soiled transport cage flooring were measured after drying treatments. When applied after a water spray wash treatment, flowing air at approximately 50°C for 15 min lowered the numbers of Campylobacter to an undetectable level. This represents a tremendous savings in drying time and suggests a potential commercial application. Static heat at similar temperatures was not nearly as effective, and unheated flowing air was moderately effective, but less so than hot air. Processors may be able to use a forced hot air treatment to dry cages between flocks, lessening the number of Campylobacter on cage flooring, thereby decreasing the potential for cross-contamination during live haul.

SUMMARY Dried cassava pulp (DCP), a by-product of cassava starch factory processing, contains a large quantity of starch. Therefore, it is certainly worthwhile to investigate its use as an energy source for poultry feed. Two experiments were conducted to examine the potential use of DCP for broilers. Growth, carcass traits, length and weight of digestive organs, and nutrient digestibility were determined in broilers fed diets containing 0 to 16% DCP. Seven-day-old mixed-sex chicks (n = 240) were randomly distributed to 5 dietary treatment groups through 42 d of age (experiment 1). In experiment 2, a total of 50 chicks were randomly allotted to individual cages at 15 d and fed 1 of 5 diets for 10 d to measure digestibility. Results showed that growth performance and nutrient digestibility decreased with increasing levels of DCP. In most cases, these parameters did not change significantly when DCP was at or below 8%. A significant increase in gizzard weight and a reduction in abdominal fat were also found in broilers fed DCP. In conclusion, it is suggested that DCP be used as an energy source at inclusion levels up to 8% in broiler diets.

SUMMARY Microbiological concerns in food plant sanitation that relies heavily on physical and chemical methods for removing and killing bacteria could be reduced by the use of non-chemical intervention methods. This initial work on the effects of electrostatic space charge on biofilms shows promise as a viable intervention option for reducing bacterial contamination on surfaces. Natural bacterial populations from a poultry processing facility were collected, allowed to multiply and form biofilms, and assessed for susceptibility to negative air ionization. A small chamber with an electrostatic space charge system was used to treat the mixed bacterial populations that were grown on stainless steel coupons (1 × 4 cm). The object of the system was to transfer a strong negative electrostatic charge to bacteria that were attached to coupons at the base of the chamber. The system effectively decreased the survival levels of bacteria on the stainless steel, with a reduction efficiency of 99.8%. All of the swab samples taken from coupons were culture positive for bacteria, and the bacterial counts from the ionized surfaces were significantly less than for the non-ionized surfaces (P < 0.01). These results demonstrate the potential efficacy of negative air ionization against bacterial contamination on surfaces in the poultry processing environment.

Three hatcheries were surveyed using the Biotest Reuter Centrifugal (RCS) air sampler and conventional Petri-plate procedures. The RCS sampler was more sensitive in detecting fungi at low levels of contamination. Marked differences in fungal and bacterial levels were detected among the three hatcheries and were attributed to operational and decontamination procedures. Microbiological evaluation of the hatcheries showed higher bacterial and fungal levels on hatching days compared to non-operational days and after cleaning.

Some types of grain sorghum contain tannins which are deleterious to poultry performance. The quantitative test for sorghum, while useful, cannot feasibly be employed in quality control programs in which quick results are needed at the elevator or feed mill. Two qualitative tests, the “scratch” test and the “bleach” test, are described. These tests will help quality control personnel detect sorghums that contain tannins.

Salmonella Enteritidis is a leading food-borne pathogen in the United States, with many outbreaks in humans traced back to shell eggs. As a result, the implementation of effective strategies for reducing Salmonella Enteritidis in commercial layer flocks has become a critical public health and economic objective. In this paper, we share the findings of 2 multistate USDA-National Integrated Food Safety Initiative grant teams and their work aimed at Salmonella Enteritidis reduction in shell eggs. One project, led by K. Venkitanarayanan, is using plant-derived antimicrobial molecules as dietary supplements to reduce Salmonella Enteritidis colonization of the digestive and reproductive tract of chickens. The same molecules are being evaluated for their effect on Salmonella Enteritidis in egg wash solutions. The project led by S. Kariyawasam used on-farm investigation and novel bacterial typing methods to study Salmonella Enteritidis transmission in diverse layer environments to update and optimize Egg Quality Assurance Programs that will significantly reduce Salmonella Enteritidis contamination of shell eggs. The current US Food and Drug Administration Egg Safety Rule and Egg Quality Assurance Programs are based on critical control points and best management practices developed from studies of large flocks (>50,000 hens) conducted in the 1990s, indicating that opportunities exist to improve preharvest programs to reduce Salmonella Enteritidis contamination. This paper will share the findings of these 2 projects.

SUMMARY Two experiments and 3 field trials were conducted to examine the usefulness of a novel bedding material for rearing Large White commercial turkeys. The control bedding was pine shavings (PS) in both experiments and all trials. The novel bedding, aGroChips (AC), is a chopped paper product made from cotton lint waste, gypsum, and old newsprint following a proprietary paper manufacturing process. In both experiments, hens and toms were reared according to typical industry techniques. In the first experiment, use of AC resulted in significantly (P < 0.05) heavier toms and hens. In the second, the toms brooded and reared on AC were significantly (P < 0.05) heavier than those brooded and reared on PS, whereas toms brooded on one bedding and then reared on the other were intermediate in weight. There were no differences in final cumulative FCR or carcass yield in either experiment. Three field trials were conducted with Large White commercial turkey hens in which the hens were brooded either on PS or AC, with both groups reared on PS. There was a mean increase of 0.2 kg in BW, a decrease (improvement) of 0.03 in FCR, and an increase of 3,200 kg per trial for AC-brooded birds (based on 16,000 hens placed per brooder house). A hard, dry litter crust was observed in the AC houses. With subsequent testing, further changes in the manufacturing process to create a hard, durable pellet may result in a more usable and useful bedding material.

SUMMARY Effect of access to wood shavings and processed paper in the litter bath of modified cages on performance, gizzard activity, plumage condition, and peck damages was studied for layers fed a wheat-based diet. Egg production was similar for all treatments, but birds with access to paper showed higher feed consumption than the control birds and birds with access to wood shavings. This resulted in a corresponding difference (P < 0.05) in feed utilization. A significantly higher AMEn was observed for birds with access to wood shavings than in the control. Consumption of wood shavings and paper from the litter bath was 4 and 11 g/hen per day, respectively. Weights of empty gizzard and gizzard contents were considerably higher for birds with access to wood shavings. The median particle size in the duodenum decreased with access to wood shavings. In contrast, birds with access to paper showed a higher mean particle size in the duodenum.

SUMMARY Functional foods are foods enriched with single ingredients, which influence 1 or more functions of the consumer in a favorable way, exceeding the effects of normal adequate nutrition. Consumers can expect health benefits from these products. The production of functional poultry meat is a promising future perspective, although the market share of such products will be small. The objective of the present paper was to summarize some examples of functional poultry meat. Substances of interest for this purpose are fatty acids and antioxidants. Enrichment of poultry meat with these health-promoting substances is not really a new approach, but there exists a potential for meeting the recommended daily intake for humans despite a probable negative effect on product quality. In the past, many papers were published showing that poultry meat can be enriched with conjugated linoleic acid, omega-3 fatty acids, and Se in such a way that 100 g of enriched tissue meets 3 to 11, 70 to 130, and 60% of the recommended daily intake for humans, respectively. However, the occurrence of tough meat (conjugated linoleic acid) and an increased liability to oxidation (omega-3 fatty acids) may impair the use of functional poultry meat. More research is needed, both on these negative effects on human requirements for these substances and possible interactions between enriched components.

Eggshell fragments, paper pads from chick boxes, and fluff samples were obtained from three commercial primary breeder hatcheries and analyzed for the presence and level of salmonellae with identical laboratory methods in 1991 and 1998. Overall, 29 of 180 samples (16.1%) from the three hatcheries in 1998 were contaminated with salmonellae, whereas in 1991, 11.1% of the overall samples were found to be salmonellae positive. Salmonellae were detected in 1.7% of eggshell fragments, 1.7% of fluff samples, and 48% of the paper pad samples in 1998, whereas 15.2, 4.5, and 12% of these type samples, respectively, were salmonellae positive in 1991. Although the percentage of positive samples was slightly higher in 1998 than 1991, from an enumeration standpoint, the salmonellae contamination in primary breeder hatcheries seems to have improved in the past 7 yr. In 1998, less than 4% of the positive samples had high levels of salmonellae, whereas in 1991 36% of the positive samples had high numbers of salmonellae. Primary broiler 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 dramatically reduced or eliminated.

Pathogenic bacteria such as Salmonella and Campylobacter on poultry products have been linked with cases of human intestinal disease. Inadequate poultry processing procedures may play a role in producing products that contain high concentrations of Salmonella and Campylobacter. The purpose of this paper was to determine whether different processing procedures provided significant variation in the bacterial contamination of raw, ready-to-cook carcasses. In this experiment, broiler chickens were processed with and without skin as well as with and without evisceration procedures. Standard processed chicken carcasses, with intact skin and viscera removed, had lower bacterial counts than did carcasses without skin or carcasses containing intact viscera (“New York dressed”). Current processing procedures widely used within the poultry industry yield superior product with regard to microbiological quality when compared to the alternative procedures described in this paper.

A 46 day trial was conducted to evaluate the use of shredded newspaper as a litter material for broilers. Four litter treatments were used: 1) wood shavings (WS), 2) wood shavings mixed with paper (WSP), 3) shavings layered over paper (S/P), and 4) paper layered over shavings (P/S). Litter material had no effect on body weight, feed conversion, mortality, or percent leg problems. Feed consumption during days 39 to 46 was significantly higher for broilers grown on WS and ESP. The incidence of breast blisters was lower for birds in the WS treatment than for birds in the other treatments. Newspaper in combination with wood shavings can be a suitable litter if litter moisture can be controlled.

SUMMARY Recent years have seen commercial broilers reach market weights at systematically younger ages. These broilers have more efficient growth rates and higher meat yields due to advances in breeding programs and improvements in poultry husbandry, health, and nutrition. Nonetheless, some critics have voiced concerns with possible negative impacts on the skeletal integrity of broilers. To address these concerns, we provide in this paper time trends of breeding values for 11 to 14 yr for 5 skeletal (limb) health traits in broilers of 3 pedigree pure lines. Results presented are based on well over a million chickens per line. Of the 5 traits, 4 had low heritabilities with the other being low to moderately heritable. Yet through intense and persistent selection, incidence of limb issues has not worsened and has declined in 4 of the traits.

SUMMARY Viral infections impose a great threat to backyard chicken production among poor rural households in developing countries. These infections limit the contribution of chicken production in improving the livelihoods of poor communities, particularly in Africa. Chicken viral infections lack treatment options; control and prevention depend primarily on adoption of vaccines and good farm management practice such as the institution of biosecurity measures. In backyard production systems, these control options are less practical and less feasible to implement. Research has demonstrated the role of genetic diversity of farmed animals and birds in explaining variation in resistance to infectious diseases and suggests that heterogeneous populations are less susceptible to disease than homogeneous populations. Local African chicken ecotypes have high genetic diversity and have demonstrated the ability to survive persistent exposure to pathogens and harsh environmental conditions. This suggests that local African chickens have the genetic potential to enhance breeding strategies for resistance to viral infections. Despite the ongoing threat of infectious disease and dynamic of diseases epidemiology attributed by climate change, little has been done to harness the genetic potential of local African chicken ecotypes to breed for resistant traits. To lay the foundation for future research, this review paper presents a summary of challenges facing current chicken viral infections control and prevention options in local African chickens, and gives an overview of documented information on the genetic diversity and population structure of local African chicken ecotypes.

SUMMARY Microbiome plasticity in chickens provides an attractive target for future potential therapeutic platforms. However, a better understanding of the chicken microbial ecology and how interventions such as xylanase addition can modulate this is needed. Interest in xylanase as an essential additive for livestock in manipulating growth performance has been reported as early as 1980s. In this paper, we describe how a new xylanase leads to an array of benefits in broilers, not only by improving broiler performance and nutrient digestibility, but also by clearly improving gut health. Gut health improvements are demonstrated by better intestinal morphology, different volatile fatty acid profile in the gut and even promotion of beneficial over pathogenic micro-organisms in the intestinal tract. Our study confirms that supplementation of xylanase at the lowest dose of 30,000 U/kg (10 g/t) and above significantly improves broiler performance and digestibility. Furthermore, the observation that xylanase can modulate broilers’ intestinal morphology and microbial content beneficially, by stimulating Lactobacilli growth and thus exerting a prebiotic effect, provides novel and useful insights for future applications.

SUMMARY The immune system is complex, with redundant and overlapping functions. Identifying the correct immune parameters to study the immune status of an animal is challenging. Nutritional immunologists often measure different isotypes of antibodies, hematological parameters, parasite loads, functional assays of macrophages and T cells, pro- and anti-inflammatory cytokines, phosphorylation status of proteins involved in signaling pathways, and several other parameters to identify the immune status of birds. Papers in which authors misinterpret immune parameters are common. This article discusses the drawbacks of some of the common interpretations of several immunological assays available for nutritional immunologists.

SUMMARY The poultry industry is considered one of the most efficient industries in producing animal protein. Poultry production consists of several main segments: broilers, commercial eggs, turkeys, ducks, and other poultry, including geese, guinea-fowl, pheasants, quail, and ratites. Currently, ostrich meat is marketed as a healthy red meat because it is characterized by high polyunsaturated fatty acid contents, low saturated fatty acid content, and low cholesterol level compared with red meats, such as beef, while tasting similar to lean beef. Ostrich meat contains lower sodium and higher iron contents than other kinds of meat, making it preferable to hypertensive people and those with anemia. Taken together, ostrich meat is considered as an ideal red meat for individuals seeking healthier lifestyle. Moreover, many different ostrich products, such as leather and feathers, are used by people. The current review paper considers the quality characteristics of ostrich meat, including physical traits, and compares it to other types of meats, such as bovine and other poultry meats.

SUMMARY Several plant-derived antimicrobials have been tested under laboratory or research farm conditions and have been shown to be effective in reducing the colonization and shedding of Salmonella Enteritidis from laying hens and broiler chickens when added to the feed. How well these particular compounds or essential oils work under commercial conditions is yet to be determined. Some of the practical implications of using these compounds in commercial poultry feed or diets are discussed in this paper. In general, an ample supply of many of these compounds exist, they are relatively easily mixed with other feed ingredients, and are effective at relatively small amounts. The cost of adding to the feed is still a variable and the total economic effect can only be estimated at this point.

SUMMARY In this paper, we present a review of the current knowledge of calcium and phosphorus metabolism as it relates to homeostatic mechanisms in poultry; contrasts with mammalian systems, as well as information that is available for mammalian systems but not for avian systems, are included. The importance of understanding these homeostatic mechanisms and their effect on Ca and P absorption are discussed briefly in the context of correctly formulating poultry diets. Clearly deficiencies, excesses, or imbalances in Ca and P result in a cascade of changes, including increases or decreases in the absorption of these 2 minerals from the intestinal lumen. The effect of these changes on the actual digestibility of Ca and P from ingredients or diets has not been determined yet; most of the methodologies we used for the determination of P digestibility are done under deficient conditions. The methods used to determine the release of Ca and P from diets when phytases were used were also done under deficient Ca and P conditions. Given the effect of Ca and P homeostatic mechanisms on absorption, methodologies and, possibly, the quantitative the effect of these homeostatic mechanisms on values generated for Ca and P should be reviewed before they can confidently be applied.

SUMMARY The use of exogenous feed enzymes in poultry diets is becoming a norm to overcome the adverse effects of antinutritional factors and improve digestion of dietary components and bird performance. In this paper, an overview of the science behind the use of feed enzymes and the current status of enzyme technology is provided. Responses to enzyme supplementation are often variable and the reasons contributing to the observed variability are discussed. Though there are opportunities to enhance nutrient utilization with enzyme supplementation, there will be physiological limits to achievable responses. These limits are imposed by the pH and digesta retention time within the digestive tract. Nutritional strategies to, at least partly, overcome these limits need to be explored; potential approaches include feeding to restore functionality of crop and gizzard as well as the use of unconventionally high doses of enzymes. Anticipated future development of better forms of feed enzymes will also lower the physiological barriers.

SUMMARY Previously, we reported that feeding native Indonesian laying hens a diet containing up to 30% palm kernel meal (PKM) resulted in comparable egg production to that of hens fed a corn-soybean meal (control) diet regardless of enzyme supplementation. In the present paper, we focus on the effect of the PKM diet on nitrogen excretion, ammonia (NH3) volatilization, as well as microbial counts. One-hundred and eighty 48-wk-old local hens were allotted to 180 cages (1 bird/cage) in a curtain-sided house. Twelve diets were assigned randomly to 15 cages each. The diets were a factorial combination of 3 levels of PKM (0, 15, and 30%), 2 concentrations of a fiber-degrading enzyme [0 and 15 units β-glucanase (major enzyme) activity/kg of diet; Ronozyme VP, DSM Nutritional Products Inc., Basel, Switzerland], and 2 concentrations of phytase + protease mixture [0 and 2,000 units of phytase (Ronozyme NP) + 12,500 units of protease (Ronozyme ProAct) activity/kg of diet; both products of DSM Nutritional Products Inc.]. Diets were isocaloric (2,758 kcal of ME/kg) and contained 17.5 to 18.4% CP and were fed for 10 wk. At 4 wk, excreta DM (but not N) increased as dietary PKM concentrations increased (19.44 vs. 21.98 vs. 23.02% for 0, 15, and 30% PKM, respectively; P ≤ 0.005). However, there were no effects of enzyme supplementations on excreta DM or N. Decreases in excreta NH3 of 36 to 47% (P ≤ 0.0001) associated with PKM concentration or of 11 to 18% (P ≤ 0.05) associated with the use of fiber degrading enzyme were observed. Although phytase + protease supplementation did not show a significant effect on NH3 reduction, interaction effects of enzymes with PKM on NH3 were observed. Moreover, increasing PKM to 30% resulted in increased Lactobacillus spp. and reduced coliform/Escherichia coli counts (P ≤ 0.005), and lower (P ≤ 0.05) excreta pH. Interaction effects between PKM and individual enzymes used on Lactobacillus spp. or between PKM and both enzymes on coliform/E. coli were observed.

The allocation of resources for maintenance, growth, reproduction, and health is a dynamic throughout the life of an animal. Resources are finite, and where allocations are directed is a function of an individual's genetic background, stage in the life cycle, and environmental challenges. Included in this paper are discussions of the concept of resource allocation with examples from experiments.

Although the transition from cage housing to alternative systems commenced more than 20 yr ago, there is still an ongoing need for information supporting system understanding, system development, and genetic selection. Cannibalism remains one of the largest problems in these housing systems. Furthermore, recent developments in feed prices have increased the price of animal feed, raising production costs of eggs. Replacing feedstuffs with cheaper self-grown crops might be a possible solution to lower feed costs. In Belgium, and more specifically, in the Kempen region, corn is a widely grown crop that is usually used for feeding dairy cows, yet a ground mix of dry corn grains and a small part of the cob, known as corn cob mix (CCM), can also be used as poultry feed. In this paper the effect of the fibrous feed CCM on the prevalence of cannibalism on hens with trimmed and untrimmed beaks is investigated. The results show a positive effect of CCM on mortality; nevertheless, the mortality in the groups of untrimmed hens was very high, indicating the importance of beak trimming. Furthermore, a positive effect of CCM on egg weight was observed.

Viral and bacterial diseases remain a threat to the poultry industry and countermeasures to prevent and control them are needed due to production losses. With the continued threat of exotic and emerging diseases and concern over the use of antibiotics in animal production, there is a serious and urgent need to find safe and practical alternatives to prevent or control pathogens. Identification of new tools for the design of new immunological interventions or therapeutic antimicrobials to reduce microbial pathogens in poultry is now required more than ever. Immunological interventions to reduce microbial pathogens in poultry would be of great value to the poultry industry and to the consumer. We have been advocating boosting immunity and encouraging the host to utilize its innate immune system to control and clear infections. Our research has addressed the use of innate immune mechanisms and components to develop new immune modulators (prophylactic and therapeutic) and the characterization and production of antimicrobial peptides as potential immune modulators in poultry. Dietary bioactive food components that interact with the immune response have considerable potential to reduce susceptibility to infectious diseases. With this premise, this paper asks and answers a series of pertinent questions on the utilization of avian immunity for increasing resistance to a variety of potential pathogens problematic in today's commercial poultry industry. Using experimental data to provide answers to these questions, we hope to stimulate a dialog between avian immunologists and nutritionists that results in coordinating and integrating their expertise into specific practical solutions that will benefit the industry and improve the well-being of commercial poultry.

There is a need to evaluate the position paper and guidelines set forth by the United Egg Producers (Washington, DC) and the American Veterinary Medical Association (Schaumburg, IL) on feeding practices and nutrient levels provided during a molt. This pilot study was undertaken to learn if a complete cessation of lay could be achieved with daily feeding while using an alternate morning and evening feeding schedule. This was an effort to mimic the fast that a bird experiences in a natural setting. The hens were fed the amount they would eat in 4 h during the morning one day and again the evening of the next day. Some hens ceased production in the third week and others in the fourth week, with zero production for all hens occurring during the fifth week. The return to 50% egg production was achieved from wk 7 to 8. Peak egg production occurred from the eleventh to twelfth weeks postmolt, reaching a level only 5 to 6 percentage points below the first cycle. This feeding protocol resulted in complete cessation of lay, allowing for a more uniform and complete restoration of the ovarian and oviductal tissues. This restoration is necessary for an effective economical postmolt period of egg production.

SUMMARY Mycoplasma gallisepticum (MG) is a persistent, highly transmissible chicken and turkey pathogen. Infections of the organism can yield significant losses in performance and associated economics to all sectors of the poultry industry. In this paper, potential and realized effects of MG on the poultry industry are discussed along with currently available and developing control methods. Available methods of MG control largely include stringent biosecurity and biosurveillance practices within the turkey and broiler sectors of the poultry industry and live attenuated MG vaccine strains that are approved for use only within the commercial egg layer industry. Although largely effective, MG breaks within these industries still occur, demonstrating that further means of control are required. Alternative means for consideration include bacterins and subunit vaccines, although their applicability may be limited by associated vaccination protocols. Further means under consideration include novel live attenuated MG strains and recombinant bacterial and viral species. Optimally, control methods would be applicable to all poultry and be safe, cost effective, and efficacious. Current research regarding novel MG vaccines is addressed herein.

Although a variety of scholarly papers and books classify chickens and turkeys as granivores, they are omnivores and do not have the food preferences, digestive anatomy, or nutritional strategies that would classify them as granivores. Their wild relatives consume a very wide variety of food items of both plant and animal origin, and seeds are not often a primary component. Intake of insects by jungle fowl chicks and wild turkey poults exceeds 50% of their diet, and adult females increase their intake of insects at the time of reproduction. In the case of jungle fowl, termites and bamboo mast are preferred foods in the area of Southeast Asia where domestication likely occurred. The nutritional strategy of omnivores is a composite of that of faunivores, frugivores, granivores, and herbivores. Appreciating the nutritional strategy of birds that eat diverse types of foods illuminates the potential capabilities and limitations of generalists, like chickens and turkeys. The marriage of comparative genomics with comparative nutrition is likely to be fertile ground for future advancements in applied poultry nutrition.

SUMMARY Data are scarce for relative effectiveness of the liquid hydroxy analogue of Met (MHA-FA) relative to DL-Met (DLM) in turkeys. In the current paper, 2 experiments are presented in order to determine the relative effectiveness of liquid MHA-FA. In trial 1, female 1-d-old Hybrid Converter turkeys were fed 13 different corn-soy diets supplemented with graded levels of DLM, diluted DLM (65%), or liquid MHA-FA (0.07, 0.14, 0.21, 0.28%) from d 7 to 50. DLM (65%) treatments can be regarded as an internal standard for the validation of exponential regression analysis. In trial 2, male 1-d-old BUTA Big 6 turkeys were assigned to 63 battery cages for 21 d. Treatments consisted of a basal corn-soy diet and 2 series each containing graded levels of either DLM (0.100, 0.200, 0.300%) or liquid MHA-FA (0.154, 0.308, 0.462%). The ratio between both products at the 3 corresponding inclusion levels was 65% weight/weight. In both trials, basal diets were formulated to be deficient in Met + Cys but adequate in all other nutrients and energy. Exponential regression analysis revealed a relative effectiveness for weight gain and feed conversion of liquid MHA-FA of 68 and 56% vs. DLM in trial 1, respectively, and of 66 and 44% in trial 2, respectively. These findings support the hypothesis of a relative bioeffectiveness of approximately 65% of liquid MHAFA as compared with DLM.

SUMMARY Four trials were conducted to evaluate Bacillus subtilis spores as a direct-fed microbial for improving broiler performance. In trials 1 to 3, straight-run Cobb 500 broiler chicks were grown to 42, 42, and 39 d, respectively, to evaluate diets containing Calsporin (0.05%; contributing spores at 0.003% level), an alternative growth promoter, compared with control basal diets. The additive significantly increased BW in all experiments (average +0.113 lb or +2.90%) and decreased feed conversion ratio in 2/3 trials (average 3 trials −0.027 lb of feed/lb of body weight or −1.46%) without affecting mortality. In trial 4, on new litter with a used litter covering and relatively high stocking density (0.67 ft 2 /bird or 0.0622 m 2 /bird), Ross × Hubbard HiY equal mixed-sex chicks were grown to 49 d of age. On all sides of pens, 34 in. high corrugated paper was used to prevent crossover of test additive but provided minimal ventilation and caused wet litter. Chick quality was substandard due to omphalitis. Bacillus subtilis spores (0.003%) treatment gave best BW and feed conversion results (+0.446 lb or +8.66% and −0.146 lb of feed/lb of body weight or −6.92%) compared with control treatment though not significantly better than bacitracin-methylene disalicylate (BMD) (55 ppm) or Bacillus subtilis spores plus BMD. Mortality was significantly lower in control than the combined additive treatment (in which no culling and large differences in growth increased mortality of weaker chickens). Bacillus subtilis spores improved broiler chicken BW and feed conversion ratio and in a direct comparison successfully replaced BMD.

SUMMARY In Denmark organic production of broilers (chickens for meat production) has expanded since 1996, when only a few farmers produced approximately 6,000 broilers. At that time, the broilers were sold directly to customers. At present, the yearly production is 350,000 broilers, and professionals organize the sale. Organic broiler production should comply with the overall goals for organic farming. This new production system differs from the conventional system due to specified standards. The production period is prolonged because broilers need to be at least 81 d old when slaughtered, and these chickens are genetically programmed to be slower growing with a maximum growth rate of 30 g/d. Additionally, daily access to roughage, organic feed without coccidiostats, and outdoor pasture areas is required. In the present paper the organic production system and data concerning growth, feeding, animal health, and slaughter quality is described based on an investigation conducted on 9 Danish farms in 1998. This investigation is the first of organic broiler production in Denmark.

Seventy-five unvaccinated chickens were divided into three equal groups. Chickens in group A received RDVF [Lentogenic strain of Newcastle disease virus (NDV)] vaccine oculonasally at 7 d of age and through drinking water at 4 wk of age. Chickens in group B were vaccinated with LaSota (Lentogenic strain of NDV) in the same way. Group C birds were kept as unvaccinated challenge controls. Five birds from each of these groups were moved to separate pens at 7 wk of age and were challenged with a field isolate No. 105 of virulent NDV (C1, based on monoclonal antibody grouping or Asiatic type, which was isolated from a disease outbreak). Similarly, five birds from each of the groups were moved to different pens at same age and challenged with the reference strain of the virulent NDV. All the unvaccinated birds died postchallenge, but both vaccinated groups withstood the challenge. Serum samples were collected from all three groups at different times, and antibody levels (against NDV) were measured by hemagglutination inhibition test, passive hemagglutination test, and enzyme-linked immunosorbent assay. The possibility of Asiatic-type NDV causing outbreaks in commercially vaccinated flocks is discussed in this paper.

Bacteria, including human enteropathogens, can penetrate the outer structures of the egg. There are several mechanisms employed by bacteria to gain entry to the egg. The most likely area on the egg to be penetrated is the air cell end, especially when temperature differential and moisture are favorable. The natural defenses that an egg has against such attack are generally not adequate to completely protect the egg from bacteria. The implications and consequences of bacterial penetration of the shell and membranes are serious, including potential dissemination of human pathogens to the hatchery, grow-out flock, and final product. This paper reviews the mechanisms involved in bacterial penetration, methods used to detect penetration, and the stages of modern production which lend themselves to shell penetration and the subsequent potential contamination of many chicks.

The efficacy of several organic acids against growth of molds typically found in animal feed was determined. A plate assay was used in which paper disks soaked in a spore solution were placed on the surface of agar plates containing increasing concentrations of the respective organic acid. Mold growth radiated from the disks, and the radius was considered indicative of the degree of inhibition as compared to a control. The efficacy of each of the organic acids against the various molds varied substantially. Valeric acid, propionic acid, and butyric acid displayed the highest efficacy against all molds with the effective concentrations ranging from 0.05 to 0.25%. Other acids, including acetic acid, lactic acid, and benzoic acid, required concentrations of 10 lb/ton or more for effective mold inhibition. Susceptibility of mold to inhibition by organic acids was in the order Fusarium spp. > Aspergillus spp. > Penicillium spp., with Fusarium spp. being the most susceptible mold.

This paper reviews the characteristics of cassava root meal and the problems and considerations involved when using it in poultry diets. A high starch content and a low percentage of protein and amino acids are cassava's main nutritional traits. However, when cassava root meal is used in poultry diets, other factors should be taken into consideration, including cyanogenic content, high level of potassium and silica, lack of carotenoids, and dustiness. Cassava's normal rate of inclusion in poultry diets in the European Union is about 25%. The inclusion of cassava root meal in poultry feeds will depend on the price and availability of energy and protein sources, synthetic amino acids, and pigments.

Light and methionine supplementation for molting hens have been the focus of attention in may different research papers. The present experiments examined the combined effects of additional light prior to molting and methionine supplementation in molt feed on the performance of molted hens. Additional light or methionine supplementation in molt feed had no significant effect on most of the performance criteria observed in the two experiments. However, the did increase feed cost, utility cost, and incidence of body-checked eggs in both experiments. These result give reason to question the efficiency of supplying 24 hr light for 7 days prior to molt and using TSAA levels greater than 0.60% or protein levels greater than 15.90% in molt feed.

This paper reports factors that determine the susceptibility of individuals to bacterial, viral, and parasitic diseases and toxins, as well as their humoral and cell-mediated immune responses, Interactions of genotypes and environments are major factors in the allocation of resources to disease defense. These allocations are dynamic and vary throughout the life of an individual. Allocation of resources to defend against disease may occur at the expense of growth, feed conversion, or other factors. Furthermore, an individual cannot simultaneously have a strong defense against all disease agents. Virulence of infectious agents and host-pathogen relationships are also important factors in an individual's susceptibility. Since any individual's level of defense against a given agent is not constant, chance is also a factor, for exposure to a disease agent can occur when the individual's defense level is low or high.

Waxy corn sometimes becomes available to the feed industry when its supply exceeds the demand of the wet milling industry. Several research papers in the past have evaluated the feeding value and/or metabolizable energy (ME) of waxy as opposed to normal corn. Unfortunately, several artifacts present in most of these studies complicate an interpretation of published data. True metabolizable energy (TMEn) assays were conducted on three sets of normal and waxy versions of the same corn hybrids. It was confirmed that corn hybrids vary in metabolizable energy. The TMEn of the three normal hybrids used in this study ranged from 3883 to 4024 kcal/kg (dry basis). However, results do not indicate a difference in TMEn of waxy vs. normal corn of the same hybrid. Thus, when formulating poultry rations with waxy corn, there is no reason to make any adjustment in metabolizable energy unless the specific hybrid is known to be low or high in caloric or protein value.

Salmonellae can penetrate egg shells without causing decomposition of the egg. As these chicks hatch, reservoirs of salmonellae can take hold on the commercial hatchery. Our study in 1990 sampled eggshells from hatching trays, belt swabs, and paper pads from three commercial hatcheries and found 75.5%, 90.9% and 66.7% contamination, respectively. This study in 1995 repeated these samples, but found 22.5%, 52.2%, and 12.1% contamination, respectively. The decline in salmonellae contamination is both dramatic and encouraging, resulting from several important factors.

Nutritionists rely on the assumption that feed is digested in a manner which is independent of both the ingredient matrix of the diet and the genetics and physiological status of the bird. This fact is evident when observing feed formulation in the poultry industry and in particular the manner in which energy and amino acid specifications are met through ingredient mixing. Such assumptions about digestion may not be entirely valid, however. Additivity of metabolizable energy, for example, is a fundamental tenet of poultry nutrition which is beginning to look less and less secure. The reasons stem from a lack of recognition of the differences in intestinal maintenance energy costs placed on the bird through use of specific ingredients and, more importantly, the role of intestinal microflora in energy and protein utilization. This paper attempts to highlight some recent (and some not so recent) findings which suggest that our reliance on the current formulation systems may overstate their robustness to dietary changes.

Focal ulcerative dermatitis (FUD), commonly referred to as “breast buttons,” is a chronic skin disease affecting unfeathered skin over the keel of the breast of turkeys and occurring most frequently in males. A series of six studies with male turkeys (n=11,680) examined risk factors associated with the occurrence of FUD. Factors studied included age, litter treatments (perlite, lime, or brooding on crenelated paper), litter type (pine sawdust, soft pine shavings, coarse pine shavings, peanut hulls, or find pine shavings), litter conditions (moisture, pH, or ammonia), commercial strain of turkey, and body weight. In all studies, occurrence of FUD is low (

Reported in this paper are factors which can increase differences between experimental group means and/or reduce variation with groups. Factors which affected the precision of research results included sex and body weight distribution with experimental caged flocks; comb type and beak trimming which influenced social rank; dose of chemicals and infectious agents and antigens; and chicken-human relationships. Experimental precision was especially affected when these factors influenced some but not all experimental groups. Increased precision of experimental procedures allows for reducing the numbers of animals and/or observations needed for experiments.

The nutritional requirements of broiler breeders and the effect of feed makeup on their performance has been the subject of considerable research. The present paper reviews the literature available on the subject, examining the effects on parameters such as egg production, egg weight, egg composition, fertility and hatchability, offspring performance, and body weight. The importance of amino acid intake (especially of lysine and methionine) and its relationship with dietary protein is discussed. Special emphasis is given to literature dealing with the effects of diet protein on fertility and hatchability and of the effects of egg weight on offspring performance. The impact of body weight on broiler breeder performance is described.

The application of feed restriction in the production of meat-type (broiler) chickens is controversial. Commercial broilers are invariably fed ad libitum. Fisher [1] noted that even a slight restriction of feed intake might affect the final body weight of broiler chickens adversely. Reece et al. [2] also observed that more adverse than favorable results have been achieved. However, recent research [3] shows that broiler performance may be improved by preventing chickens from feeding for short periods of time throughout the day. North [4] found that mature body weights of broiler chickens are not affected provided that feeding is not interrupted for more than 2 hours at a time. The demonstration of catch-up growth in broiler chickens [5, 6, 7, 8] has also raised new possibilities. This paper examines new developments in feed restriction of broilers and evaluates the potential application of short-term feed restriction to broiler chicken production. The mechanisms responsible for catch-up growth, and the factors which influence this phenomenon, are also discussed.