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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.

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 Biomasses such as peanut hulls or tree clippings have the potential for use in the production of chars, which can in turn be used as tools for environmental improvements. The purpose of this study was to evaluate the effectiveness of chars on reducing NH3 volatilization from poultry litter when used as a surface-applied treatment. The chars used were produced from 3 biomasses: peanut hulls, pine chips, and coconut husks. Peanut hull char (pH 9.2) was produced by pyrolyzing peanut hulls at 400°C for 30 min. The pine chip and coconut husk chars were acidified with sulfuric acid at a final concentration of 53% and had a pH of 2.0. Application rates were 0, 0.24, 0.37 + 0.37, and 0.73 kg/m2 to the floor of pens containing broilers at a commercial density (0.07 m2/bird). The addition of peanut hull char did not reduce NH3 concentrations in the air compared with untreated pine shavings bedding material. However, the use of acidified chars resulted in significant linear reductions in NH3 concentrations. The reduction in NH3 by the acidified chars was likely due to a combination of litter pH reduction and NH3 immobilization by the H2 SO4 on the char. Bird performance was not adversely affected by any of the char treatments.

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 Greater understanding of the mechanisms affecting NH3 volatilization from reused broiler bedding is needed to determine pathways for mitigating NH3 emissions. A chamber acid trap (CAT) system was developed to provide an improved laboratory method for determining NH3 volatilization from litter or cake samples and for assessing treatment technologies to decrease NH3 losses from poultry litter. The CAT system offers precision control of air flow rate through sample chambers as well as straightforward, precise determination of the amount of N volatilized. This article outlines the basic setup of the CAT system. The system can be utilized and modified for researching specific mechanisms involving physical, chemical, or biological treatments affecting NH3 volatilization from litter or cake.

Broiler transport coops become soiled with feces during use. When this fecal matter contains Campylobacter, the result can be cross-contamination of subsequent flocks that were previously free of this important human pathogen. Because washing and sanitizing coops requires large amounts of water and is not always effective enough to justify the expense, few broiler companies wash and sanitize dump coops between flocks. In this lab-scale study, a tap water spray was effective in lowering the numbers of bacteria, including Campylobacter, associated with broiler transport coop flooring. Immersion in a chemical sanitizer after spray washing did not enhance the antibacterial effect. It is possible that sanitizing treatments could be made more effective by using higher concentrations of chemicals, high temperature treatment, or high pressure or repeated applications of water spray. However, such changes would come at a cost. Research is needed to find new and innovative ways to lower bacterial numbers in broiler transport coops without undue use of water and the associated expense.

A general recommendation is to keep ammonia levels in poultry facilities below 25 ppm. Unfortunately, a reliable, inexpensive method of determining ammonia levels has not been well established. To address this situation, ammonia concentrations, as determined by the Ammonia Quick Test and the passive dosimeter tube, were compared to the ammonia concentration determined by the gas detector tube. The ammonia Quick Test estimated ammonia levels accurately at levels of 20-25 ppm of ammonia. The passive dosimeter tubes estimated average ammonia levels accurately at low levels of ammonia. Comparisons of ammonia concentration to relative humidity suggest that ammonia can increase much more rapidly than relative humidity.

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.

Inorganic sodium selenite (NaSe; 0.1 and 0.3 ppm) and organic selenium yeast (Sel Plex 50: OR; 0.1 and 0.3 ppm) were provided in the diets of broilers placed on four different litter types: 1) ACR paper (diced recycled low-density fiber paper treated with boric acid, 4.5%), 2) shavings (pine wood shavings), 3) diced/cross-cut news print, or 4) 50% mixture of ACR and shavings, in a 32-pen broiler house with curtain side walls. Subjective body feathering scores ranging from 0 (no feathers) to 5 (best) were determined at 3, 5, and 6 wk of age. In experiment 1, feather scores at 6 wk of age were improved significantly with OR supplementation at 0.3 ppm compare to all other selenium treatments, and in Experiment 2 both levels of OR supplementation were associated with improved feathering compared to NaSe supplementation. ACR paper caused reduced feathering in both experiments, and neither NaSe nor OR were sufficient to overcome the problem. In both experiments, OR was associated with better feathering for broilers on all litters at all ages. Performance parameters such as feed conversion ratios were not affected by selenium source even though feathering, an energetically expensive function, was improved in the OR-fed birds.

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.

Two 46-day floor pen experiments evaluated low- and high- density pelleted newspaper as a broiler litter material. Experiment 1 compared fresh pine sawdust (FPS) to fresh low-density paper (FLP). Experiment 2 compared FPS, fresh low-density paper containing an adhesive (FLPA), and fresh high-density paper (FHP) with the used sawdust (UPS) and used low-density paper (ULP) from Experiment 1. All fresh paper materials were placed in pens at one-half the depth (3.8 cm) of the FPS (7.6 cm). Litter type (sawdust vs. paper), age (fresh vs. used), and paper density (low vs. high) had no effect on 46-day body weight, feed conversion, or mortality. Litter moisture was similar and caking was absent among treatments in Experiment 1. In Experiment 2, the FLPA resulted in increased cake formation. Broilers reared on FHP had the lowest incidence of breast blisters in Experiment 2. Both low-(without adhesive) and high-density pelleted newspaper are suitable broiler litter materials when placed at one-half the sawdust litter volume.

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 Development of a net energy (NE) system in poultry has been a topic of research for many decades, following its successful implementation in pigs. However, up to now, no such system for poultry is in use, as the added value of a NE system in poultry over the current AME system(s) has not yet been demonstrated. In this paper, the merits and limits of a NE system in poultry are discussed for fast-growing broilers.

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 A ban on using antibiotics as growth promoters in the diet of commercial poultry and swine in most developed countries and the public trend in consuming organic animal products have resulted in increasing the use of natural substances in feeding farm animals. Among different available alternatives, the beneficial impacts of phytogenic feed additives (PFA) and organic acids (OA) on the performance of poultry—and specifically broiler chickens—have been proven by previous researchers. Mostly it has been reported that PFA and/or OA improve the performance of animals by modulating the intestinal microflora in favor of beneficial bacteria like lactobacilli. There are also some published papers showing that the addition of PFA and/or OA is not significantly beneficial on broiler chickens’ performance. It has been suggested that rapid absorption or metabolism of these additives upon entering the duodenum is the reason. Therefore, protecting the additives from early metabolism and absorption can be an approach to increase their effectiveness.

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 A literature review on production and control of nuisance odor from land application, processing, and storage of broiler litter is presented in this paper. The review identifies several odor production factors and odor control strategies based upon research conducted on litter and manure from poultry and other species. Published research lacks information on odor emissions and control of odor as affected by litter moisture conditions, loading and transportation of litter, application site factors, and weather conditions (prior, during, and after litter application). For this reason, several studies, mostly from peer-reviewed publications on ammonia emissions from broiler operations and various species were included. It was inferred that conditions that cause increased ammonia emissions may also be favorable for the production and increase in odor from land application, processing and storage of broiler litter. New nuisance odor assessment tools, such as the model odor from feedlots setback estimation tool (OFFSET), provide a better control on setback distances for improved community relations. Consideration of wind speed, direction, and weather condition during land application, incorporation of land-applied litter, covering of litter in storage and while in transportation, and processing, such as composting of litter and mortality, were all considered as practices that help minimize odor emission.

Odors from broiler production facilities are the consequence of odorant molecules produced by microbial activity in the litter. The impact of odor on the public can be evaluated by the frequency, intensity, duration, and offensiveness of the odors. Currently, much of the work reported in the scientific literature is directed toward measurement of odor intensity by determination of the odor concentration through threshold olfactometry. Several researchers have reported values for odor concentration in or near broiler production facilities, ranging from 80 to 2,000 odor units, and some researchers have reported odor emission rates. This paper briefly reviews measurement methods for odor concentration and intensity, summarizes the values reported in the literature for odor concentration for broiler houses, discusses the relationship between odor concentration measurements and odor intensity, and reviews the literature to determine if a correlation between odor concentration and ammonia and dust emissions exists.

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.

Before any significant progress can be made in altering textural characteristics of a meat product, the basic profile of the meat and the possible alterations in that profile due to processing procedures must be known. A number of papers have been published addressing ways to optimize the textural characteristics of broiler breast meat. Changes in broiler processing procedures and processing time lines have been adopted by processors because of the results of these studies. While the number of breeder hens processed annually is much lower than the number of broilers, adding value to the end product could result in new innovative product forms for this niche market meat. The traditional goal for heavy fowl processors has been to remove the muscles, dice or grind the meat and sell it as an ingredient in other products. In an effort to expand the product forms of breeder hen meat, which is usually assumed to be tough and chewy, this study was designed to profile the texture of the meat based on four postchill (PC) deboning times. Instrumental and sensory profiles of the breast meat from hens were determined. There were significant texture differences in the cooked fillets due to deboning time. Cooked yield for the fillets deboned 24 h PC was lower than for fillets deboned 2 or 8 h PC.

Ideal amino acid ratios for chicks during the early growth period (0 to 21 days) are well documented by empirical evidence, but suggested ratios for older birds are in need of confirmation. Based on best empirical estimates of lysine, SAA, and threonine requirements of broiler chicks during 0 to 21, 21 to 42, and 42 to 56 days of age, together with new knowledge of maintenance contributions to the total requirement for these amino acids, it appear that the ideal ratio of SAA and threonine to lysine may change very little as birds advance in age and weight toward a 56-day market weight. This paper presents regression equations that predict both digestible and total lysine, SAA, and threonine requirements at any age or weight between hatching and 56 days.

Experiments with broiler chickens usually compare the effects of treatments when birds are killed at the same time. However, producers need to know the value of treatments on birds killed at the same weight, since their goal is to produce birds for a certain market. The curve expressing body weight as a function of feed consumption is described very well by a second-order polynomial (quadratic curve). Given an observed body weight and feed intake and a standard curve, it is possible to produce a curve that describes the relationship of body weight to feed consumption for any flock. Once this curve is estimated for a flock, it is possible to estimate the feed consumption (and therefore feed conversion or efficiency) for any weight of bird that could be slaughtered. This paper describes an electronic spreadsheet template for Microsoft Excel that predicts feed efficiency for any weight of broiler based on the observed body weight and feed consumption of a flock. The prediction may be valuable in comparing research results and rewarding contract growers for truly superior performance.

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.

This paper reports the results of a growth study with subsequent carcass analysis to investigate the potential of betaine to replace DL-methionine as an essential amino acid supplement in broiler diets. Starter and grower diets were formulated to be deficient in sulfur amino acids, then supplemented with various combinations of DL-methionine and betaine. All diets were supplemented with choline chloride to ensure adequate methyl group supply. Growth, feed conversion, and breast meat yield were significantly improved by added DL-methionine, but not be betaine. There was no evidence that betaine can reduce the need for supplemental methionine in broiler diets deficient in sulfur amino acids.

In broiler production many factors influence profitability. Growth modelling provides a mechanism through which these factors can be identified scientifically. Over the past decade advances in statistics, computer science, and broiler nutrition have allowed a number of groups to develop growth models for boiler production. This paper provides a framework to be used to evaluate the appropriateness and effectiveness of using a growth model for a particular broiler operation. Two growth models were evaluated using this technique: the Novus Growth Model IGM™ and the ARO growth model Chickpot™. These models explained between 78 and 92% of the observed variation in live weight for commercial growout data. This level of explanation is sufficient for using models in many commercial decision-making applications.

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.