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Adaptation of Nigerian indigenous chickens (NIC), FUNAAB-α (F-α) and Transylvanian naked neck chickens (TNN) raised during hot-dry season under humid tropical environment was compared during a 4-week period. A well-adapted NIC (n = 12; 6 males and 6 females), a newly developed F-α (n = 12; 6 male and 6 females) and a newly introduced TNN (n = 12; 6 male and 6 females) chickens aged 36 weeks were used for this experiment. Heart rate (HR), respiratory rate (RR), rectal temperature (RT) and skin temperature on comb (COM), wattle (WAT), breast (BRE) and under wings (WIN) were monitored between 13.00 and 14.00h twice a week for four weeks. Wattle temperature (p = .017) and BRE (p = .000) differ significantly among the genotypes. Transylvanian naked neck chickens recorded higher WAT than NIC, though not different from F-α. Nigerian indigenous chickens had lower BRE temperature than other two genotypes. Significantly higher WAT (p < .001) and WIN (p < .05) were recorded in cocks than in laying hens. In contrast, laying hens had significantly (p < .001) higher RR and HSI than cocks. There was interactive (p < .05) effect of sex and genotype on BRE. Nigerian indigenous cocks and hens exhibited lower BRE than others, except F-α cock. There were positive significant correlations between WIN and WAT in the three genotypes. In NIC, COM had positive correlation with WAT (r = .532) and WIN (r = .696). Heart rate was positively correlated with WAT (r = .608) and WIN (r = .697) in F-α, and WIN (r = .512) in TNN chickens. In conclusion, the three genotypes can adequately adapt to the prevailing conditions of humid tropics. Reduction of feather on the neck and breast and higher heat loss capacity in TNN chickens could help the birds adapt to hot-humid environment. The two sexes could adapt to the tropical region. Cocks lose body heat predominantly via non-evaporative means while hens employ evaporative heat loss mechanism.

The present case is an unusual report of cutaneous fowlpox with an atypical appearance and incidence in broilers. Gross skin lesions were noticed in 41-day-old commercial broilers during the veterinary inspection at a processing plant in the north of Iran. The skin lesions were only observed on feathered skin areas of the broilers and remained unnoticed until slaughter. Round, nodular or coalescent, elongated, reddish-brown proliferative lesions were mainly located on the back, thighs, and proximal areas of the neck of broilers. Nonfeathered skin, including the wattle, comb, eyelids, and legs, were not affected. This condition incurred high losses due to a 5.3% condemnation and trimming of carcasses. Cutaneous lesions were sampled for histopathology and molecular virology for further investigations. Histopathology revealed multifocal necrotic dermatitis with epidermal eosinophilic cytoplasmic inclusion bodies in the skin lesions. Molecular investigations confirmed the presence of fowlpox virus (FWPV) in the proliferative lesions, with further investigations identifying two FWPV genome populations, one carrying a portion of the reticuloendotheliosis virus (REV) and the other a nearly complete REV provirus. Furthermore, the 4b core protein gene-based molecular analysis clustered the field virus into clade A of the genus Avipoxvirus.

Birds obtained by embryo engineering are used to study embryo development and to produce transgenic birds. As this method of producing birds still generate strong emotions of the public opinion head ornaments, testes and semen characteristics of sex chimera roosters were examined to check whether they differ from chickens obtained by non-manipulated methods. Measurements of head ornaments, testes and semen were correlated with each other. Semen quality factor (SQF) was calculated, as well as the level of fluctuating asymmetry (FA) of bilateral traits (wattles and testes). Positive correlation was found for comb width and wattle length and comb thickness and sperm concentration. Semen characteristics and FA did not exceed the level encounter in other chicken lines. Results obtained indicate that germline chimeras are similar in appearance of secondary sexual traits, and semen and testes characteristics to chickens produced in non-manipulated way.

It is estimated that each year over 19 million pullets in the United States have their combs partially trimmed at a young age to improve egg production and feed efficiency. A possible disadvantage of trimming is that the comb and wattles may be essential for thermoregulation during hot weather allowing for conductive cooling of the blood through vasodilation of superficial vessels in these integumentary tissues. The objective of this study was to investigate the effects of partial comb and wattle removal, performed at 21 d of age, on the ability of White Leghorns to thermoregulate before, during, and after an imposed heating episode that averaged 34.6°C for 50.5 h. An increase in mortality at 20 h and body temperature at 48 h post initiation of the heating episode demonstrated that hens with trimmed comb and wattles were not able to cope with heat stress as effectively as controls. The increase in wattle temperature in controls as compared to trimmed hens during the heating episode and following heat stress provides supportive evidence that blood pools to the peripheral surface for conductive heat loss. During high temperatures typical of summer, trimmed hens attempted to compensate for their lack of ability to transfer heat from their comb and wattles to the environment through increased proportion of panting and wing spreading. Under less extreme conditions with lowered ambient temperatures, the trimming of the comb and wattles did not impair the ability of hens to thermoregulate, as body temperatures and behavior were similar to controls with no mortality. Egg weight was the only production parameter adversely affected by the trimming of the comb and wattles as compared to controls. The implication is that hens need their combs and wattles to thermoregulate effectively during periods of high environmental temperature. Pullets should not be subjected to a comb and wattle trim if they are housed in laying facilities that are not appropriately cooled during the summer.

Infrared thermography (IRT) is increasingly applied as a noninvasive technique for measuring surface body temperature alterations related to e.g. stress, emotions and leg pathologies in avian species. As a basis for the validation of IRT as a future tool for veterinary diagnostics such as detection and/or prediction of subclinical footpad pathologies in broiler chickens, this study explored effects of manual restraint at two different ages on footpad temperatures. Head region temperatures were applied as additional measures of emotional arousal and stress. The study demonstrated that footpad temperatures dropped during 10min of restraint (p

The purpose of this study was to analyze the associations among fluctuating asymmetry, duration of tonic immobility, heterophil-to-lymphocyte ratio, and one-legged standing, crooked toes, or footpad dermatitis in chickens. In experiment 1, cocks (n = 96; 36 wk old) from 11 Spanish breeds and a White Leghorn population that showed one-legged or normal standing were used. There were no significant differences for the relative fluctuating asymmetry, the duration of tonic immobility, and the heterophil-to-lymphocyte ratio between both groups of cocks, with mean values of one-legged standing birds being similar to those of normal birds. Thus, this pain-related behavior is not associated with some measures of well-being, fear, and stress. In experiment 2, cocks (n = 106; 36 wk old) from 9 Spanish breeds and the White Leghorn population that showed crooked or normal toes were used. Group effect was not significant for the relative fluctuating asymmetry and duration of tonic immobility. Hetero-phil-to-lymphocyte ratio and heterophil number weresignificantly greater (P < 0.001) in cocks with crooked toes and smaller in cocks with normal toes, with the opposite being true for lymphocyte number. Thus, this leg problem is associated with the stressfulness of birds and does not contribute to their well-being or fear levels. In experiment 3, cocks (n = 68; 36 wk old) from 5 Spanish breeds with or without footpad dermatitis were used. Group effect was significant for the relative asymmetry of toe length (P < 0.05), the relative asymmetry of cocks with footpad dermatitis being larger. Group × breed interaction was significant for the relative asymmetry of wattle length (P < 0.001), with the difference between cocks with footpad dermatitis and normal cocks being significant in one breed. In this breed (Red-Barred Vasca), fluctuating asymmetry of wattle length was significantly greater in cocks with footpad dermatitis, suggesting that this leg problem negatively affects the well-being of cocks. © 2009 Poultry Science Association Inc.

The purpose of this study was to analyze the effect of housing system and cold stress on the heterophil-to-lymphocyte ratio, the fluctuating asymmetry, and the tonic immobility duration of chickens. In experiment 1, hens (n = 120; 36 wk old) from 5 Spanish breeds and a White Leghorn population, which had been housed in pens with or without access to an outdoor area from 20 wk of age, were used. The effect of housing system on heterophil-to-lymphocyte ratio varied from breed to breed, differences between housing systems being significant (P < 0.05) in 2 breeds. In these breeds (Red-Barred Vasca and Birchen Leonesa), heterophil-to-lymphocyte ratio was significantly greater in hens housed in deep litter. Housing effect was significant for the relative asymmetry of leg length (P < 0.01), wattle length (P < 0.05), and the combined relative asymmetry (P < 0.05), the relative asymmetry of hens housed in deep litter being larger. There was no significant difference for the duration of tonic immobility between hens housed in deep litter or free range. Thus, hens with access to an outdoor area were less stressed than hens without access to an outdoor area, although the fearfulness was similar in both groups of birds. In experiment 2, cocks (n = 120; 36 wk old) from 4 Spanish breeds, a synthetic breed, and the White Leghorn population, which had been housed in cages with or without a cold stress (0 to 10°C) from 24 wk of age, were used. Cold x breed interaction was significant for heterophil-to-lymphocyte ratio (P < 0.05), differences between cold-stressed and control birds being significant in 2 breeds. In these breeds (Red-Barred Vasca and Buff Prat), heterophil-to-lymphocyte ratio was significantly greater in cold-stressed birds. Cold stress effect was significant for the relative asymmetry of toe length (P < 0.001) and the combined relative asymmetry (P < 0.05), the relative asymmetry of birds with cold stress being larger than that of control birds. Thus, cold stress seriously negatively affects the welfare of cocks. ©2008 Poultry Science Association Inc.

Estrogens play a key role in sexual differentiation of both the gonads and external traits in birds. The production of estrogen occurs via a well-characterized steroidogenic pathway, which is a multistep process involving several enzymes, including cytochrome P450 aromatase. In chicken embryos, the aromatase gene (CYP19A1) is expressed female-specifically from the time of gonadal sex differentiation. Ectopic overexpression of aromatase in male chicken embryos induces gonadal sex reversal, and male embryos treated with estradiol become feminized; however, this is not permanent. To test whether a continuous supply of estrogen in adult chickens could induce stable male to female sex reversal, 2 transgenic male chickens overexpressing aromatase were generated using the Tol2/transposase system. These birds had robust ectopic aromatase expression, which resulted in the production of high serum levels of estradiol. Transgenic males had female-like wattle and comb growth and feathering, but they retained male weights, displayed leg spurs, and developed testes. Despite the small sample size, this data strongly suggests that high levels of circulating estrogen are insufficient to maintain a female gonadal phenotype in adult birds. Previous observations of gynandromorph birds and embryos with mixed sex chimeric gonads have highlighted the role of cell autonomous sex identity in chickens. This might imply that in the study described here, direct genetic effects of the male chromosomes largely prevailed over the hormonal profile of the aromatase transgenic birds. This data therefore support the emerging view of at least partial cell autonomous sex development in birds. However, a larger study will confirm this intriguing observation.

Smyth line chickens (SL) are an animal model to study human autoimmune vitiligo. Vitiligo in SL chickens is characterized by a post-hatch loss of feather melanocytes (MC) resulting in feather depigmentation. The etiopathology of this disease remains unclear, however, a hypothesis that cell-mediated immunity (CMI) plays an important role in the destruction of melanocytes has been proposed based on previous studies. To support this hypothesis, the delayed wattle response (DWR) to MC lysates was examined in SL chickens and normally pigmented, MHC-matched controls (Brown line, BL; Light Brown Leghorn, LBL) to determine whether vitiliginous SL chickens have MC-specific CMI. Chickens were challenged in one wattle with a lysate of either embryo- or feather-derived cultured MC. Lysates of chick-embryo-fibroblasts (CEF) associated turkey herpesvirus (HVT) vaccine and syngeneic CEF were used as positive and negative control, respectively. Vitiliginous SL chickens exhibited a significantly greater DWR to feather-MC but not to embryo-MC and CEF than nonvitiliginous SL chickens and normally pigmented controls. The DWR to feather-MC peaked at 3 to 5 days post feather-MC lysate injection. Immunohistochemical staining of DWR-positive wattle tissue revealed extensive lymphocyte infiltration at the site of feather-MC injection consisting primarily of T cells (TCR2+, CD4+ or CD8+ T cells). These observations support the presence of MC-specific CMI in SL chickens with vitiligo. The anti-MC CMI activity appears to be specific to MC derived from feathers. SDS-PAGE analysis of different sources of MC lysates revealed a 43 kDa missing band in the lysate of feather-MC established from SL chickens. No other obvious protein pattern differences that could account for the feather MC-specific CMI response in vitiliginous SL chickens were observed among the MC lysates.

Two experiments were conducted to induce the delayed footpad reaction (DFR) to killed Staphylococcus aureus antigen. In Experiment 1, tracheal, cloacal, and choanal swabs were collected from chickens prior to sensitization with S. aureus to determine the carrier status of S. aureus. The second experiment compared the DFR to the delayed wattle reaction (DWR). Chickens were subjected to single or multiple sensitizations in the neck with S. aureus antigen between 4 and 6 wk of age. One week later, birds were challenged with S. aureus either in the right footpad or wattle. The left footpad or wattle was injected with PBS. The thicknesses of the footpad or the wattle were measured up to 96 h postchallenge. The recoveries of S. aureus from the choanal slit and trachea were significantly higher than that of the cloaca (P < 0.001). Birds of Experiment 1 showed a significant DFR (P < 0.0001) following intradermal challenge with killed S. aureus that was sustained through 48 h postchallenge with no difference in the DFR between carrier and noncarrier birds. In Experiment 2, the thicknesses of the footpad and wattle were significantly increased following challenge with S. aureus (P < 0.0001), with the footpad showing a greater response than the wattle (P < 0.001). Three sensitizing dosages, as compared to two dosages, resulted in a less pronounced DFR and DWR (P < 0.02). These results indicate that the DFR can be used as a delayed reaction model in the study of staphylococcosis in poultry.

1. Two-way selection for delayed-type hypersensitivity wattle reaction (DWR) competence to BCG antigen was carried out over 4 generations, using a flock of White Leghorn chickens. DWR was measured by intradermal injection of BCG into the wattle of chickens. 2. Selection for DWR was effective. The generation means of average selection differential, selection response and realized heritability were 1.15 mm, 0.77 mm and 0.70 respectively. Correlated responses were found in body weight, egg weight and hatchability. In all of these traits, the L line (selected for low wattle reaction) showed higher values than the H line (high reaction). 3. Specific trends in gene frequencies were observed at the major histocompatibility B and alkaline phosphatase Akp loci. 4. Significant line differences were found in graft-versus-host reaction competence and Marek's disease resistance. In both characters, the L line was higher than the H line. No line differences were found in phytohaemagglutinin response, phagocytic activity or immune responses.

The aim of the present study was to analyze the relationship between fluctuating asymmetry and the mean value of several bilateral traits (toe, leg, wing, and wattle lengths, and leg width) and sperm quality variables (volume, appearance, concentration, motility, morphological abnormalities, and acrosome and membrane integrities) in different breeds of layers. In total, 165 roosters were sampled at 36 wk of age. There was no significant correlation between fluctuating asymmetry and sperm quality variables. There was a positive association (P < 0.01) between sperm motility and concentration, and between sperm concentration and volume. Sperm motility was positively correlated (P < 0.001) with morphologically normal sperm. The membrane integrity did not correlate with motility. This study shows different results for the association between sperm quality variables and morphological traits. There was a negative association (P < 0.05) between toe length and membrane integrity and between leg length and sperm motility. In disagreement with the expected results, wattle length did not correlate with any sperm quality parameter. In general, roosters with longer legs had longer toes and wings, whereas those with longer wattles had longer toes, legs, and wings. Breed effect was significant for the sperm motility index (P < 0.001), concentration and membrane integrity (P < 0.05), and morphologically normal sperm (P < 0.01). Spanish breeds had similar sperm quality variables to the White Leghorn population, although the Blue Andaluza (a Spanish breed) showed smaller values for sperm motility index and concentration and membrane integrity. Breed effect was not significant for any fluctuating asymmetry, with values ranging from 1 to 6% of the trait value; however, breed effect was significant for all of the morphological traits (P < 0.001). The CV was higher for ejaculate volume and concentration, intermediate for semen appearance, motilities, and morphologically normal sperm, and smaller for membrane and acrosome integrity. In conclusion, the results suggest that fluctuating asymmetry is of limited use for assessment of rooster sperm quality. Some morphological traits (toe length, leg length, and leg width) might be associated with some sperm quality variables (motility and membrane integrity). © 2011 Poultry Science Association Inc.

1. Neurogenic inflammation has been studied in the anaesthetized adult hen using a variety of different stimuli. 2. Plasma extravasation was produced following antidromic stimulation of the external mandibular ramus of the trigeminal nerve which innervates the skin at the angle of the jaw and the anterior part of the wattle. 3. Stimulation of the wattle by external application of mustard oil, thermal and mechanical stimuli, as well as intradermal injection of substance P and bradykinin, all produced plasma extravasation. 4. These results demonstrate that, in contrast to previous findings in the pigeon, at least in the trigeminal of the chicken peripheral C-fibre nociceptors have similar physiological characteristics in relation to the neurogenic inflammatory mechanism to those seen in mammals.

The current study was undertaken to examine the reactivity of anti-chondroitin sulfate monoclonal antibody, CS-56, to the comb and wattle galactosaminoglycans containing varying proportions of L-iduronic acid. Galactosaminoglycans were isolated from mature rooster comb and wattle tissues and were separated into four fractions (I, II, III, and IV), which were precipitable with 18, 25, 40, and 50% ethanol, respectively. Each fraction was examined using an ELISA technique. The results demonstrated presence of CS-56 epitope in galactosaminoglycans from both tissues. Most (>99%) of the epitope were found in Fractions III and IV, which were galactosaminoglycans rich in D-glucuronic acid. Fractions I and II, which were dermatan sulfates rich in L-iduronic acid, showed little or very weak antigenicities.

Galactosaminoglycans from mature rooster comb and wattle tissues were separated into five fractions by ethanol precipitation. An average of 90% total uronic acid was recovered in Fractions I to III. Fractions I and II were dermatan sulfate with relatively high proportions of L-iduronic acid (61 to 80%), but this uronic acid was a minor component (30%) in Fraction III, in which D-glucuronic acid was the major uronic acid. Digestion with testicular hyaluronidase suggested that most if not all of the galactosaminoglycans in Fractions I to III were copolymers containing both L-iduronic acid and D-glucuronic acid. Fractions IV and V contained much lower proportions of L-iduronic acid and showed broader electrophoresis bands than did Fraction III.

The growth response of poultry to androgens is ambiguous, with both increases and decreases being reported. This may reflect the use of pharmacological doses. The present study examined the effect of physiological concentrations of androgens on growth of intact male, intact female, and castrated chickens. Physiological concentrations of androgen were attained by subcutaneous silastic implants. In mammals, androgens have both androgenic effects on the reproductive organs and anabolic growth-promoting effects on body and muscle growth. Some androgens, for instance 5 alpha-dihydrotestosterone (5 alpha-DHT) have high androgenic activity (5 alpha-DHT greater than testosterone) but others, e.g., 19-nortestosterone, have high anabolic activities (19-nortestosterone greater than testosterone greater than 5 alpha-DHT). The relative effects of testosterone, 5 alpha-DHT, and 19-nortestosterone on growth were compared in chickens. In young, intact male and female chicks, growth was suppressed by 1.0-cm silastic implants of testosterone and 5 alpha-DHT (5 alpha-DHT greater than testosterone). Castrated chicks were implanted with implants of various sizes (.3, 1.0, and 3.0 cm) containing testosterone, 5 alpha-DHT, or 19-nortestosterone. The androgens inhibited body weight gain: 19-nortestosterone reducing body weight at all three doses, 5 alpha-DHT reducing body weight at the intermediate and high doses, and testosterone tending to reduce body weight only at the high dose. Testosterone (3.0 cm), 5 alpha-DHT (all doses), and 19-nortestosterone (all doses) reduces skeletal growth, as indicated by shank-toe length. In contrast to their growth-suppressing effect, all three steroids exerted an androgenic effect; stimulating comb and wattle development (19-nortestosterone greater than 5 alpha-DHT greater than testosterone). It is concluded that androgens are androgenic but are not anabolic in chickens.

The aim of this study was to investigate the possibility of combining the naked neck gene with a genetic background that has been optimized for feed efficiency of laying hens at moderate temperature. In 1997, the naked neck gene was introduced into a line selected for low residual feed intake. In 2003, after 6 generations of introgression, 8 males and 56 females heterozygous for the NA*NA mutation were used to generate all 3 genotypes (NA*N/NA*N, NA*NA/NA*N, NA*NA/NA*NA), in 2 hatches, for rearing in Taiwan and France, respectively, at 3-wk intervals. Growth performance, anatomical traits, laying traits, and feed efficiency were recorded in each country. In addition, comb and rectal temperatures were measured in Taiwan. Performance was generally lower and mortality of laying hens was higher in Taiwan (11%) than in France (1%). Genotype × environment interactions were rare: genotype × environment was observed only for body weight at 10 wk of age and was close to significance for egg weight. The laying performance was significantly decreased in Taiwan by about 25%. The naked neck genotype had a negative effect on body weight and a positive effect of clutch length and egg weight. It also affected heat dissipation traits such as wattle length and rectal and surface temperature measurements. There was a clear additive and negative effect of the NA*NA mutation on rectal temperature. Feed intake and residual feed intake were increased in the homozygous carriers of the NA*NA mutation, which may improve heat tolerance of the low residual feed consumption (R−) line. Feed efficiency tended to be better in NA*NA/NA*NA hens in both environments. Thus, the introduction of the NA*NA mutation in the R− background appeared to be favorable from the viewpoint of feed efficiency, but it did not improve laying performance in a subtropical environment. Other factors than temperature, such as diet composition and lighting regimen, may be involved.

The purpose of the present study was to analyze the relationship between incidence of vent pecking, fluctuating asymmetry, heterophil to lymphocyte ratio, and tonic immobility duration in chickens. The experiment (140 birds in three different replicates) measured the fluctuating asymmetry of several traits (middle toe length, leg length, wing length, wattle length, and leg width), the heterophil to lymphocyte ratio, and the tonic immobility duration in 20-week-old pullets of five Spanish breeds of chickens (Blue Andaluza, Quail Castellana, White-faced Spanish, Red-barred Vasca, and Birchen Leonesa), and a White Leghorn population, with and without evidence of suffering from vent pecking. The number of birds per breed was 20, 24, 12, 20, 18, and 46, respectively. There was a significant difference between vent pecked and non-vent pecked birds on the relative fluctuating asymmetry of middle toe length (P < 0.05), the relative fluctuating asymmetry of birds who suffered from vent pecking being larger. The combined relative fluctuating asymmetry of the five traits approached levels of statistical significance (P = 0.08). There was a significant difference (P < 0.001) in heterophil to lymphocyte ratio and tonic immobility duration between vent pecked and non-vent pecked birds, the ratio being higher and the duration being longer in the group of birds that suffered from vent pecking. Thus, vent pecked birds were more asymmetrical, stressed and fearful than non-vent pecked birds, having increased relative fluctuating asymmetry, heterophil to lymphocyte ratio and tonic immobility duration. Differences were consistent across the breeds. Results indicate that vent pecking is associated with other measures of stress e.g. fluctuating asymmetry, heterophil to lymphocyte ratio, and tonic immobility duration. © 2007 Elsevier B.V. All rights reserved.

Stress responses in laying hens were mediated by continuous infusion of adrenocorticotropin (ACTH) via osmotic pumps. The ACTH was dissolved in saline solution (0.85%), and each pump delivered 8 IU of ACTH per kilogram of BW per day at the rate of 1 microL/h for 7 d. Control hens received pumps loaded with saline. Measurements were made at 6 d postpump implantation, unless otherwise indicated. The ACTH-treatment increased BW and total carcass, rear half of carcass, intestinal, and liver weights. Proximate analyses of liver showed increases in dry weight, moisture, protein, fat, carbohydrate, and ash content. Weights of the front half of the carcass, as well as weights of the abdominal fat pad, heart, head, feet, and skin were unaffected by ACTH-treatment. Plasma corticosterone, glucose, cholesterol, and high-density lipoproteins were increased by ACTH, whereas triglycerides were decreased. Feed and water intake, total excreta, and excretory DM were all increased in ACTH-treated hens. The ACTH decreased carbohydrate in excreta, whereas ash, protein, fiber, and gross energy of excreta were unaffected. The ACTH did not affect digestibility of dry matter, proteins, carbohydrates, fats, or gross energy; however, absorption of ash, protein, carbohydrates, and gross energy were increased by ACTH. Antibody levels to sheep red blood cells, cell-mediated immunity (wattle index to phytohemagglutinin-phosphate), and relative spleen weight were reduced by ACTH, whereas heterophil:lymphocyte ratio was increased. Reproduction in hens was negatively affected by ACTH treatment, as measured by cessation of laying on the third day of treatment, atretic follicles, and decreased oviduct weight.

1. Genetic selection for growth to enhance production may be associated with stress and with modified physiological and behavioural phenotypes which depress male primary broiler breeder fertility. 2. We hypothesised that male serum testosterone (T) and corticosterone (C) concentrations might correlate with fertility, sexual behaviour, and testicular, comb and wattle size. 3. Cockerels from two genetic strains (A and B) of primary broiler breeder were penned individually with an average of 10 females across 5 age periods (30 to 51 weeks) to evaluate male fertility, behaviour, serum T and C, and comb, wattle and testicular dimensions. 4. Strain A males had higher T at age periods 2, 4 and 5 than Strain B. Both strains had basal concentrations of C, apart from an elevated concentration for Strain B in period 5. 5. Strain B had a weak but significant, positive correlation between sexual behaviour and T and C, while Strain A males with higher C had larger combs and wattles. 6. Neither T nor C correlated with fertility. We conclude that evaluation of these endocrine factors (quantifiable measurements with the potential to correlate with fertility) alone seems insufficient to predict male fertility potential in these strains of primary broiler breeder.

Bisphenol-A (BPA) has been reported to bind to the estrogen receptor (ER) and also to act as a xenoestrogen on the reproductive system of many species. In our previous study, a high dose of BPA disturbed the growth of the comb and testes of male chickens. In this study, the exposure of relatively low doses of BPA on the growth of the male chicken phenotypes was investigated. White Leghorn male chicks were orally administered various doses of BPA (2 microg to 200 mg/kg) from 2 weeks of age, and thereafter the comb, wattle and testes were examined at 5, 10, 15, 20 and 25 weeks of age. Although the body weight showed no significant difference among the birds of all ages, the growth of above organs was significantly affected in the chicks even with a minimal dose of 2-microg BPA. These inhibitory effects appeared in a dose-dependent manner. Histologically, the growth of the testes was negatively affected by exposure to over 20-microg/kg BPA: namely, the development of seminiferous tubuli and spermatogenesis were severely inhibited. The mRNA expressions of ERalpha and the aromatase gene (p450arom) increased in the testes in a dose-dependent manner after BPA administration. Accordingly, even low doses of BPA delayed the growth of the male chicken phenotype either by a direct effect or by an indirect response resulting in an increase in both of the endogenous estrogen levels and hyper-sensitivity to estrogen.

The purposes of the present study were to estimate the heritability of the fluctuating asymmetry in chickens, using the restricted maximum likelihood procedure, and to evaluate the effects of age and sex on the fluctuating asymmetry. Leg, wing, and feather lengths and ear-lobe and wattle areas were measured. In experiment 1, 1,073 birds were used from 2 generations with complete pedigree of the Quail Castellana breed to estimate the heritability for the fluctuating asymmetry at 36 wk of age. The estimated heritability of absolute fluctuating asymmetry was not significantly different from zero for all 5 traits, and similar estimates were obtained for relative fluctuating asymmetry, directional asymmetry, transformed absolute and relative fluctuating asymmetry, and 3 alternative indexes of fluctuating asymmetry. The heritability of the combined absolute or relative fluctuating asymmetry was still very low, indicating that fluctuating asymmetry was determined solely by environmental sources of variation and that fluctuating asymmetry estimates should not be confounded by appreciable additive genetic contributions. The genetic correlation between sides was not significantly different from one, indicating that differences between sides were purely environmental in origin. Different traits rarely showed much correlation in their level of fluctuating asymmetry, indicating that the level of fluctuating asymmetry in all traits did not reflect equally the quality of animals. In experiment 2, fluctuating asymmetry differences among ages and sexes were investigated at 8, 12, 16, 20, 24, 28, 32, 36, and 40 wk in 360 birds from the same breed. Significant variation with age was observed in leg length, wing length, feather length (females), and wattle area (females), which was mainly related to onset of sexual maturity and adult stage. Females showed significantly greater fluctuating asymmetry for ear-lobe area than males. There were significant differences in fluctuating asymmetry for wing length, feather length, and wattle area near the onset of sexual maturity, with males having significantly greater fluctuating asymmetry than females for wing length and the opposite being true for feather length and wattle area. ©2005 Poultry Science Association, Inc.

Genetic selection in primary broiler breeders may modify skeletal structure, possibly impeding semen transfer, and could alter the size and degree of fluctuating asymmetry (FA) of bilateral traits associated with fertility. Hence, we hypothesized specific morphometric traits could predict differential fertility. Sixty primary broiler breeder males from Strains A and B (n = 30/strain) were individually housed with an average of 10 females per male. Male fertility and sperm penetration (SP) through the perivitelline layer were estimated on fresh eggs. At 50 wk, BW, keel length (KL), posterior pelvic width and length (PPW, PPL), dorsal pelvic width and length (DPW, DPL), tarsometatarsal length and width (TL, TW), comb length and width (CL, CW), and wattle length, width, and area (WL, WW, WA) were measured. Results indicated that Strain A had smaller BW, KL, WL, WW, WA, CL, CW, PPL, DPL, and DPW. A higher degree of FA was found in Strain A TL and WL (P < 0.05), yet DPW FA was greater for Strain B (P < 0.001). In addition, DPW FA negatively correlated with Strain B fertility (r = -0.369; P < 0.01); however, other FA measurements did not correlate with estimated fertility or SP. Strain A WL correlated with SP (r = 0.383; P < 0.01) and fertility (r = 0.346; P < 0.01). Results indicate DPW alteration may impact semen transfer upon copulation, as Strain A fertility negatively correlated with DPW (r = -0.298; P < 0.05). This research provides evidence that morphometric traits might be useful to predict fertility in broiler breeders.

At Generations 15 (males) and 18 (females) of a divergent selection experiment on residual feed consumption (RFC) in laying poultry, patterns of growth, feed consumption, and associated traits were monitored between the ages of 4 and 34 wk. This monitoring was done to determine how the well-established RFC and feed intake (FI) divergences between adults of the low intake R- line and of the high intake R+ line took place, in relation to the evolution of correlated traits. In males and females, BW and BW gain were higher in the R- line in the first weeks of test, but patterns of BW were quite similar in both lines afterwards. However, R- hens remained heavier than R+ females to the end of the experiment. Line difference for BW was achieved by 28 wk of age, at 2,974 and 2,094 g, and the R- line was then 135 and 133 g heavier, respectively, for males and females. After a fast initial increase in both sexes, FI diverged quickly around 16 to 18 wk of age (sexual maturity), to attain 13 g/d in males and 28 g/d in females, well before the end of the experiment. At the same time, a divergence was observed for wattle length, which was 21% higher in R+ females. Residual feed consumption gradually diverged in the two lines, and the difference became significant at 14 wk of age. At the same age, shanks were 8% longer in R+ hens. Finally, levels of triiodothyronine decreased faster in the R- line, as FI divergence was increasing. These results indicate that the RFC difference between R- and R+, lines obtained in adult birds by divergent selection lines, starts somewhat early in life. In addition, the RFC difference appears to be associated with specific growth periods, around 14 wk and 18 to 20 wk. It is at this time that large differences appear in morphological traits involved in body heat loss. No significant correlations were found between early (6 wk) measures of FI, feed efficiency, and RFC, with adult values (32 to 34 wk) for RFC and FI.

Two lines selected since 1976 for high (R+) or low (R–) residual feed consumption (RFC) from a common genetic base were compared with one another and with their F1 reciprocal crosses for traits of egg production and quality, for morphological traits, body weights, and feed consumption. Heterosis was 11, –2.5, 8, and 2%, respectively, for egg number, age at first egg, egg laying rate, and egg weight, with marked differences between reciprocal crosses for all those traits but egg number. Heterosis for wattle length and shank length was 3.8 and 1.3%, respectively, essentially because R+ × R– crossbreds, with larger mean values, resembled the R+ line for those traits, which may therefore be associated with the presence of genes linked to the Z chromosomes. On the other hand, heterosis for RFC (–3.6%) originated from similar crossbred advantage in both reciprocal crosses, thereby suggesting that RFC is not determined by sex-linked genes.

Background Uninterrupted transmission of highly pathogenic avian influenza virus (HPAIV) H5N1 of clade 2.2.1 in Egypt since 2006 resulted in establishment of two main genetic clusters. The 2.2.1/C group where all recent human and majority of backyard origin viruses clustered together, meanwhile the majority of viruses derived from vaccinated poultry in commercial farms grouped in 2.2.1.1 clade. Findings In the present investigation, an HPAIV H5N1 was isolated from twenty weeks old layers chickens that were vaccinated with a homologous H5N1 vaccine at 1, 7 and 16 weeks old. At twenty weeks of age, birds showed cyanosis of comb and wattle, decrease in egg production and up to 27% mortality. Examined serum samples showed low antibody titer in HI test (Log2 3.2± 4.2). The hemagglutinin (HA) and neuraminidase (NA) genes of the isolated virus were closely related to viruses in 2.2.1/C group isolated from poultry in live bird market (LBM) and backyards or from infected people. Conspicuous mutations in the HA and NA genes including a deletion within the receptor binding domain in the HA globular head region were observed. Conclusions Despite repeated vaccination of layer chickens using a homologous H5N1 vaccine, infection with HPAIV H5N1 resulted in significant morbidity and mortality. In endemic countries like Egypt, rigorous control measures including enforcement of biosecurity, culling of infected birds and constant update of vaccine virus strains are highly required to prevent circulation of HPAIV H5N1 between backyard birds, commercial poultry, LBM and humans.

Glycosaminoglycan fractions isolated from either comb or wattle tissue were examined using ELISA for their antigenicities to AH12, a monoclonal antibody recognizing keratan sulfate. The results showed a positive antibody binding to a sulfated glycosaminoglycan fraction from either tissue. The treatment of the same fraction with keratan sulfate degrading enzyme, keratanase, or endo-β-galactosidase resulted in a decrease in its antigenicity. These findings indicated the presence of AH12 epitope (keratan sulfate disaccharide) in both tissues.

Alzet mini-osmotic pumps were implanted subcutaneously to administer norepinephrine (NE) and epinephrine (E) to 6-wk-old line UNH 105 chickens. Dose-time studies showed the most effective NE and E dose and exposure time on two chicken cellular immune responses: the phytohemagglutinin (PHA) wattle response and leukocyte migration. Administration of 1 microgram/h NE for 72 h suppressed significantly the wattle stimulation index [2.48 +/- .3 (SE)] compared to that of saline controls (4.1 +/- .3) but enhanced mean leukocyte migration (7.7 +/- .3 versus 4.9 +/- .3). Epinephrine at 1 microgram/h for 72 h significantly suppressed the wattle index (1.8 +/- .2) compared to that of controls (2.8 +/- .3) but E at 1 microgram/h for 48 h enhanced leukocyte migration (9.5 +/- .2 versus 6.4 +/- .2). Continuous administration of NE and E at physiological levels alters cell-mediated immunity and appears to have an immune regulatory role in the chicken.

1. The effect of warmed drinking water on the performance and immunological responses of broiler breeder hens maintained at low air temperatures (5.0 degrees to 12.9 degrees C) was tested. From 22 weeks of age hens (mean body mass = 2.4 kg) were offered either warm water (27.7 degrees C; WARM; n = 24) or tap water (12.7 degrees C; CONR; n = 24) twice daily for a total time of 2.5 h or tap water ad libitum (CONA; n = 16). Food was restricted for all hens. 2. Daily water intake in the WARM hens (103 ml/kg) was similar to that of the CONR (93 ml/kg) and CONA hens (106 ml/kg). 3. There were no significant differences in either body mass change or egg production among treatment groups. 4. There was no difference among groups in heterophil/lymphocyte ratios. Similarly, there was no difference among groups in either phagocytic activity or wattle index after phytohaemagglutinin (PHA) injection. Total and IgG antibody titres to SRBC tended to be highest in the WARM hens and these titres were significantly higher than in CONR hens 14 d after challenge.

1. Bedouin chickens are kept in deserts mainly for eggs and are well adapted to arid conditions. However, deserts are also characterised by relatively cold winter nights. As a consequence of cold stress there is an involution of lymphoid organs and a depression of immunological function. We compared the performance and immunological responses of Bedouin and White Leghorn hens kept in outdoor pens in the Negev Desert during the winter. 2. Initial mean body mass was similar for the two breeds: 1525 g for Bedouin hens and 1542 g for White Leghorn hens. White Leghorns lost 7.74 g/d, compared with 0.60 g/d for Bedouin hens and produced 0.36 eggs/d, compared with 0.54 eggs/day for Bedouin hens. 3. The heterophil/lymphocyte ratio for Bedouin hens was 0.28, which was lower than the 0.44 for White Leghorn hens. Phagocytic index was higher in Bedouin hens than in White Leghorns. Furthermore, wattle index measured 24, 48 and 72 h after PHA injections and anti-SRBC antibody titres determined 10 d after challenge were also higher in Bedouin hens than in White Leghorns. 4. We concluded that the Bedouin hens were less stressed by the cold than were the White Leghorn hens.

1. Divergent selection was undertaken in a Rhode Island Red population for residual food intake, measured in males and females, using mass selection. 2. In the absence of a control line, selection response during 14 generations was estimated by the within‐year divergence between lines. 3. The direct response in residual food intake was found to be significant in both sexes, the divergence reaching almost three pheno‐typic standard deviations in each sex. 4. Significant correlated responses were obtained for food efficiency; it was improved in the low residual food intake line. Shank length, wattle length and rectal and comb temperature showed higher values in the high line, suggesting an increased heat production or dissipation. Inconsistent changes were observed for other egg production traits.

Glycosaminoglycan (GAG) fractions were isolated from papain digests of comb and wattle tissues of 52-wk-old Single Comb White Leghorn roosters and the chemical composition of each fraction was examined. Total GAG concentrations were greater in the comb than in the wattle tissue with the ratio of hyaluronic acid to sulfated GAG being similar between the two tissues. L-iduronosyl-N-acetylgalactosamine-4-sulfate was the predominant disaccharide unit in the sulfated GAG fraction.

The influence of the major histocompatibility (B) complex on acquired immunity to the avian coccidium Eimeria tenella was studied in 217 F4 segregants (B2B2, B2B5, B5B5) of a cross between inbred lines 6(1) (B2B2) and 15(1) (B5B5) and segregating haplotype combinations of UNH105 (B23B23, B23B24, B24B24), a noninbred line of New Hampshire chickens. Chickens were immunized at 6 weeks of age with 500 oocysts daily for 5 days, then challenged 14 days later with 10 000 oocysts. Responses to infection were evaluated by cecal lesion scores, body weight gain, delayed wattle reaction (DWR), and spleen weight. The F4 segregants of genotypes B2B5 and B5B5 exhibited greater immunity to challenge than B2B2 chickens. B5B5 chickens showed a significantly greater DWR following immunization and larger spleens 6 days after the challenge than either of the other genotypes. However, both B2B5 and B5B5 chickens demonstrated significantly lower lesion scores than B2B2 chickens. There were no significant differences in weight gain among these genotypes. Among 139 line UNH105 segregants, B23B23 hosts had significantly lower lesion scores than B24B24 chickens. No other differences in immune response among line UNH105 genotypes were detected.

Delayed wattle reactions (DWR) to tuberculin, diphtheria toxoid (DT), and keyhole limpet hemocyanin (KLH) were transferred to chickens with dialyzable leukocyte extracts (DLE) prepared from splenic leukocytes of chickens sensitized and reactive by DWR to the tuberculin, DT, or KLH. A DLE prepared from chickens unsensitized and unreactive to tuberculin by DWR failed to transfer DWR to tuberculin in recipients. Only chickens injected with DLE from tuberculin sensitized and reactive chickens exhibited significant (P less than .01) DWR to tuberculin. Chickens that received DLE prepared from DT sensitized and reactive chickens exhibited significant (P less than .01) DWR to DT but not to KLH. Further, DWR to both DT and KLH was transferred with DLE prepared from chickens sensitized to both antigens. Adoptive transfer of DWR to KLH in comparison to DT was more successful. Finally, the serial transfer of DWR to KLH (P less than .05) but not to DT (P greater than .05) was accomplished using DLE prepared from chickens that previously were recipients of DLE prepared from chickens sensitized to KLH and DT. Results indicate that DLE prepared from chickens contain transfer factor (TF) responsible for adoptive transfer of DWR to tuberculin, DT, and KLH.

Delayed hypersensitivity (DH) and protective immunity were transferred to nonimmune 4- and 10-week-old broiler chickens with transfer factor (TF) prepared from splenic leukocytes of chickens immunized with CocciVac D. Only chickens injected with the immune TF showed DH by wattle reaction to oocyst antigen and protective immunity to Eimeria tenella challenge infection. Chickens given a single injection of TF 5 days before challenge infection exhibited a significant (P less than .05) DH response at the time of infection. Immune TF preparations were active at concentrations of 100, 200, or 400 mg. Neither DH nor protective immunity was transferred to chickens injected with the TF-diluent control or nonimmune TF. The nonimmune TF was prepared from chickens kept free of coccidial infection. These findings indicated that TF prophylaxis produced beneficial results in nonimmune chickens by conferring some protection against challenge with E. tenella. The effects of TF on T-lymphocyte mediated protective immunity to coccidia in chickens are discussed.

We have produced allergic contact dermatitis (ACD) to low molecular weight allergens in the chicken. Sensitization was induced by the application of a high concentration of allergen to a site on the comb previously treated with dimethyl sulfoxide. Challenge, which was made on the wattle with a nonirritating concentration of allergen, resulted in a dermatitis that was grossly and histologically similar to ACD in mammals. Chickens sensitized to oxazolone reacted to that allergen and not to picryl chloride, and conversely. This model provides a unique system wherein to study the T-cell and B-cell contributions to the generation, maintainance and expression of the ACD response.

Naked-neck (NaNa and Nana+) and normal hens, all dwarf (dw), were compared for laying performance in two groups at 15 to 20 or 30 degrees C. Naked-neck hens, especially homozygotes, weighed less only at the cooler temperature. Body fatness was not different. Normal, but not naked-neck birds, showed a depression in food intake and egg output at 30 degrees C. In the hot environment mean egg weight and egg mass output were highest for naked-neck homozygotes. At the cooler temperature mean egg weight was also higher for this genotype, at fixed body weight. The decline in egg mass with time seemed greater for fully-feathered layers at high temperature. At moderate temperature residual food intake was slightly increased by the naked-neck gene, but owing to the reduced body weight, food utilisation was not poorer for the NaNa or Nana+ genotypes. At higher temperature Nana+ and especially NaNa hens utilised food more efficiently. An increase in wattle size and a slight decrease in body temperature were associated with the Na allele.

The levels of connective tissue constituents (hexosamine, hexuronic acid, hexose and hydroxyproline) and the composition of isolated mucopolysaccharide-peptide complexes were determined in some organs and tissue of male and female fowl treated and not treated with estradiol-17β. Most of the changes occurred in the male. Estrogen administration brought statistically significant increases in die contents of hexosamine and hexuronic acid in the cartilage of the male and of hexose in the spleen of both males and females. It also increased the hydroxyproline in the testis and in the cartilage of the male. Estrogen decreased the content of hexosamine in the combs of both males and females, and in the wattle of the female, of hexuronic acid, hexose and hydroxyproline in the liver of the male, and hydroxyproline in the breast muscle of the male. Hexosamine, sialic acid, lipid and protein contents of blood sera of estrogenized birds were substantially higher than that of the controls. Gas liquid chromatography of the lipids of the tissues indicated that estrogen administration brought about an increase in the proportion of the unsaturated fraction to the total fatty acid content.

The influence of diurnal rhythms on several immune parameters was studied. When thymic-derived lymphocytes were collected 4 times during a 24-hour period, a variation occurred in the migration ability of these ceils. The migration of T cells at 2:00 a.m. was markedly lower than at other time periods. Similar results were noted employing other T-cell tests: phytohemagglutinin wattle responsiveness and the graft vs. host assay.

Mucopolysaccharide–peptide complexes (MPS-P) from skin, comb, wattle, liver, kidney, spleen, lung, heart, ovaries, egg yolk, infundibulum, magnum, isthmus, shell gland, and vagina of the White Leghorn laying hens were isolated after extraction with acetone, papain hydrolysis, and cetyl pyridinium chloride precipitation. They were analyzed for characteristic components of the glycosaminoglycan (GAG) and carbohydrate parts of glycoproteins and for amino acids. The infrared spectra of the MPS-P were studied for detection of the GAG present. The MPS-P were submitted to cellulose acetate electrophoresis for detection of GAG and to column chromatography on an anionic resin for quantitative determination of GAG.

The influence of the major histocompatibility (B) complex on the delayed wattle reaction (DWR) to Staphylococcus aureus was studied in 109 segregants (B2/B2, B2/B5, and B5/B5) of a fourth generation cross between inbred Regional Poultry Research Laboratory lines 61 and 151. Chickens were sensitized at 6 weeks of age with S. aureus antigen. One week later, DWR was evaluated by injecting the right wattle with S. aureus antigen. Thickness measurements were taken 4, 24, 48, 72, and 96 hr after injection. A quadratic equation model was used for each bird to calculate maximum wattle thickness, hour of maximum response, and rate of response development and decline. In males, the maximum wattle thickness in response to S. aureus antigen was significantly greater in B2/B5 heterozygotes (1.77 ± .07 mm) than in either homozygote, B2/B2 (1.36 ± .13 mm) or B5/B5 (1.39 ± .08 mm). Heterozygous males reached maximum response sooner and recovered more quickly than homozygous males but these differences were not statistically significant. In females, response developed later than in males but no B complex effect was detected in either rate of development or maximum response.

Two generations of a normal (AG) strain and a dwarf (D2) strain and one generation of an F1 (AG × D2) cross-strain of broiler breeder chickens were evaluated to determine if the sex-linked dwarfing gene, dw, affects specific immune competence parameters. The lymphocyte blast transformation response using the mitogen phytohemagglutinin-M was significantly stronger among second generation dwarfs compared to either normal or cross-strain birds. A delayed-type hypersensitivity response was induced by intradermal injection of tuberculin into the wattles of sensitized birds. Dwarf and cross-strain birds had significantly larger wattle swelling indices than normal strain birds. Dwarf males and cross-strain females had significantly stronger tuberculin responses than normal strain birds of either sex at 24 and 48 hr postchallenge. In addition, the tuberculin response of normal strain birds decreased significantly between 24 and 48 hr following antigenic challenge, whereas the tuberculin responses of cross-strain birds increased and dwarf birds remained the same. The dwarfing gene had no significant effect on natural agglutinin titers to 1% rabbit red blood cell (RRBC) in either the parent or second generation. There was also no significant difference in the response of parent generation birds to sheep red blood cells (SRBC) following intravenous sensitization with 1 ml of a 1% SRBC suspension. However, second generation dwarfs had significantly lower SRBC titers than normal or cross-strain birds. Assays of cellular and humoral immunity indicated that sex-linked dwarfs may have more competent T-cell subpopulations and weaker B-cell reactivity compared to normal strain birds.

The cell-mediated immune (CMI) response to diphtheria toxoid (DT) was studied in commercial broiler breeder lines. The chickens were immunized with DT in complete Freund's adjuvant 21 days before CMI assay by delayed wattle reactivity (DWR) to DT. The DWR was shown to be a valid measure of CMI and to correlate with spleen cell migration inhibition and blastogenesis assays of CMI in vitro. In addition, each criterion of CMI was met, except for the passive transfer of DWR. These criteria were delayed timing, gross morphology, histopathology of DWR, and effect of antilymyphocytic sera on DWR. The duration of DWR over a 1-year period differed in the two lines of chickens tested. A significantly greater DWR was found in one line with all birds remaining reactive for CMI whereas in the other line 16% did not have CMI by the end of the year. The differences may reflect genetic variability within and between lines in expression of CMI.

Kinetic studies on delayed-type hypersensitivity (DTH) to Freund's complete adjuvant (FCA) have been done in spontaneous dysgammaglobulinemic chickens, which have drastically reduced serum IgG levels and highly elevated IgM and IgA levels — in comparison to chickens with normal immunoglobulin (Ig) levels. For a period of five weeks, serum Ig levels, leukocyte migration inhibition (LMIT), and wattle reaction were examined once a week. In normal chickens, FCA treatment resulted in stimulation of IgG, but did not affect IgM synthesis, whereas in spontaneous dysgammaglobulinemic chickens, FCA stimulated only IgM synthesis. Spontaneous dysgammaglobulinemic chickens could produce LMIT and wattle reactions as well as normal birds. Whereas in normal birds, both types of DTH reactions declined continuously about the third or fourth week, in immunodeficient chickens, further increments of LMIT and wattle reactions up to the fifth week persisted as evidenced by LMIT and wattle reactions even 15 weeks after sensitization. In contrast, only minimal signs of reactivity were seen in normal birds. Spontaneous dysgammaglobulinemic chickens, nearly unable to synthesize IgG even after FCA stimulation in vivo, lack suppressive mechanisms regulating the course of DTH reaction to FCA. The possible B-cell nature of the regulatory cell population is discussed.

The influence of the biogenic amines serotonin (5-HT), dopamine (DA) and norepinephrine (NE) on the phytohemagglutinin (PHA) wattle response was studied in three populations derived from line UNH 105 New Hampshire chickens. At 3 or 6 weeks of age, chicks were injected intravenously with either 5-HT, DA, NE, or a saline control. Thirty minutes after monoamine injection, 100 ug PHA-P was injected in the wattle and the thickness increase was calculated 24 hr later. Analysis of variance showed significant monoamine effects compared to controls but no difference in response among the three populations. 5-HT and NE each depressed significantly the wattle response in 3 and 6 week old chicks. DA reduced the response in both ages also but the significantly greater reduction in 6 than in 3 week old chicks indicated an age effect. These results suggest a regulatory role for monoamines in the PHA wattle response.

The skin hypersensitivity of fowls injected in the wattle with different antigens prepared from the protozoan parasite Eimeria tenella was measured at intervals throughout immunization by infection and also after the injection of antigens in Freund's complete adjuvant (FCA). In the early stages of immunization by infection, i.e., from 3 to 8 weeks after the initial inoculum of oocysts, the maximum response was found 4 hr after injection of antigen and was probably Arthus in type. At its peak, this response coincided with the presence of precipitating serum antibodies and was transferable with serum. A smaller delayed response was also present and, in the later period of testing (from approximately 10 to 18 weeks), this became much more marked whereas the 4-hr response had declined and was negligible or absent. Thus, with the method of immunization used here, once immunity became complete (i.e., no production of oocysts after a challenege inoculum), there was a change from predominantly a 4-hr response to a delayed type. However, a substantial degree of immunity was present in infected birds which had strong 4-hr responses but weak 48-hr responses. A course of injections of antigens (prepared from the parasite) in FCA induced wattle hypersensitivity but no reduction of oocyst production after a challenge inoculum.

The graft vs host (GvH) and phytohemagglutinin (PHA) wattle responses were the parameters chosen to evaluate cell-mediated immunity in aging chickens. At 6 and 24 months of age female spleen cells were significantly more effective in eliciting a GvH response than spleen cells from 1-, 2-, 12-, and 18-month-old females. The biphasic GvH response produced by female spleen cells was not observed for male spleens. On the other hand, peripheral blood lymphocytes from both males and females exhibited a single peak, 3–6 months, in their ability to produce a GvH response. The thymic-dependent PHA wattle response of males was significantly greatest at 1 month of age and declined thereafter. Once again the females exhibited a different pattern than the males. At 1 month of age the female's wattle response was significantly greater than at 3 months, but rather than declining with age the wattles of aging females responded like 1-month-old females. Several mechanisms are offered to explain the apparent age-related regression-regeneration of cell-mediated immunity in the female.

Electrolytic coagulation of areas on the diencephalon of the adult White Leghorn hen has been made with the assistance of a Stellar stereotaxic instrument and an X-ray machine. Comb and wattle factors, egg-laying cycles, acidophil counts, adrenal corticoid concentration, and histological studies of the oviducts, adrenals, and thyroid glands have been recorded. Cessation of egg-laying was brought about by lesions in the nucleus paraventricularis, median eminence, and pars tuberalis. These lesions also reduced the size of the comb and wattles. Some of the lesioned birds exhibited an increase in acidophils, possibly due to the destruction of an area controlling “normal acidophil levels”. There did not appear to be any correlation between lesioned areas and corticoid titer of any of the birds 2 weeks following the operations. Hens with lesions in the nucleus supraopticus, preoptic division, showed a thyroid histological picture that indicated a reduction in activity of the gland.

The mucopolysaccharide–peptide complexes from White Leghorn skin, comb, wattle, heart, liver, and testis were isolated and analyzed for constituent carbohydrate and amino acid units. Individual mucopolysaccharides in each tissue were characterized using several techniques. All tissues examined, except liver, contained at least two mucopolysaccharides, including a low molecular weight component. The low molecular weight component appeared to be the only substance isolated from liver. The incorporation of D-[1-14C]hexosamine into acetone-dried tissues and mucopolysaccharide–peptide complexes was investigated. Intravenously injected D-[1-14C]galactosamine accumulated in the liver to a much greater extent than D-[1-14C]glucosamine. In addition, evidence was provided which indicated that glucosamine was converted to nonhexosamine products. The increase of radioactivity associated with mucopolysaccharide–peptide complexes with increasing time coincided with a decrease in liver radioactivity.