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Influence of pharmacological manipulation of dopamine and opioid receptor subtypes on stereotyped behaviour of restricted-fed fowls.

Effects on environmentally induced oral stereotypes (object pecking and drinker directed activity) of antagonists and agonists of dopamine and opioid receptor subtypes were examined in individually caged broiler breeder fowls subjected to chronic food restriction. Three drugs in each category were injected intravenously at three doses, and their effects compared with those of a saline control treatment. With dopamine antagonists, inhibition of both stereotypes was most marked with haloperidol (D2), intermediate with clozapine (D4), and lowest with SCH 23390 (D1). Increased sitting with the high doses of these three drugs may reflect sedation. With dopamine agonists, SKF 38393 (D1) suppressed both stereotypes slightly, quinpirole (D3) did so consistently and potently, possibly reflecting preferential presynaptic action, while bromocriptine (D2) inhibited drinker-directed activity consistently, but its initial suppression of object pecking changed to delayed stimulation with the high dose. This biphasic effect of bromocriptine may reflect change from pre- to postsynaptic action. Two of the opioid antagonists, naltrexone (mu) and MR 2266 (kappa, but also mu), inhibited object pecking partially, while naltrindole (delta) and the opioid agonists fentanyl (mu), BUBU (delta), and PD 117302 (kappa) had delayed and minor effects. These results suggest that expression of object pecking, but not necessarily drinker-directed activity, depends more on activation of D2 dopamine receptors than D1 receptors, the role of D3 and D4 receptors is less clear, and activation of mu and possibly kappa opioid receptors may play a contributory role.

Animals↗

Behavioral responses of restricted-fed fowls to pharmacological manipulation of 5-HT and GABA receptor subtypes.

Effects on environmentally induced oral stereotypies (object pecking and drinker-directed activity) and other behavior (sitting, standing, pacing, preening), of preferential antagonists and agonists of central 5-HT and GABA receptor subtypes, were examined in individually caged broiler breeder fowls subjected to chronic food restriction. All drugs were injected intravenously at three doses, and their effects compared with a saline control treatment. The only significant (p < 0.05) effect of 5-HT antagonists [NAN-190 (5-HT1A), ketanserin (5-HT2), MDL-72222 (5-HT3)] was an increase in pacing with ketanserin (0.8 mg/kg). With 5-HT agonists, 8-OH-DPAT (5-HT1A) suppressed the two oral stereotypies and increased standing (all 1.0 mg/kg) and preening (0.2 mg/kg), alpha-methylserotonin (5-HT2) suppressed the oral stereotypies and increased sitting (all 1.0 mg/kg), and m-CPBG (5-HT3) suppressed drinker-directed activity (1.0 mg/kg). The GABA antagonists (bicuculline (GABAA), 5-aminovaleric acid (GABAB) had no effect, and of the GABA agonists [muscimol (GABAA), baclofen (GABAB)], muscimol suppressed preening and increased sitting, standing (all 1.0 mg/kg), and pacing (0.2 mg/kg). Most of the significant effects of serotonergic and GABAergic agents on behavior here appeared to reflect at least some degree of sedation, and there was no real evidence of any specific influence of these compounds on the oral stereotypies within the range of doses tested.

Animals↗

The effects of age on the composition of uterine fluid of broiler breeder hens and on maintenance of quality of fowl spermatozoa when stored in uterine fluid or in a synthetic medium.

We studied effects of aging of hens on some physio-chemical parameters of uterine fluid taken at 2 stages of the ovulatory cycle (12 and 18 h after the oviposition) and of uterine fluid properties as a semen diluent in vitro at 41 degrees C. The volume, pH, osmotic pressure, Na+, K+, Ca2+, glucose and total protein concentrations of uterine fluid were measured. The percentage of motile spermatozoa and the fertilizing ability of fowl semen diluted 1:9 in uterine fluid were tested throughout the laying cycle in meat-type hens and compared to those of semen diluted in synthetic medium M199. The results showed that the volume and the K+ and Ca2+ concentrations in uterine fluid decrease with the hens' aging, while osmotic pressure is significantly higher in older hens. But in spite of the composition differences, uterine fluids from hens of different ages have little influence as semen diluents either on sperm motility or on fertilizing ability. These observations suggest that the variations of the composition of uterine fluid with hens' aging does not contribute to the late seasonal decline in fertility observed during the later stages of the reproductive season in this species. In any case, uterine fluid is harmful to sperm quality in vitro, while M199 is an appropriate semen diluent at 41 degrees C. The high glucose concentration in M199, however, slightly decreases motility and the duration of the fertile period of spermatozoa.

Journal Article↗

Effects of thyroid hormones on humoral and cell-mediated immune responses in the domestic fowl (Gallus domesticus).

We investigated the effect of raising and lowering circulating thyroid hormones in young domestic fowl on antibody production and the responses of peripheral blood lymphocytes (PBL) to the mitogens concanavalin A (con A) and phytohaemagglutinin (PHA). Circulating thyroid hormones were reduced by treatment with the goitrogen, methimazole, and raised by giving implants containing thyroxine (T4) and/or triiodothyronine (T3). Raising or lowering circulating thyroid hormones had no significant effect on peak antibody titers, though the decline in titer was slower in goitrogen-treated birds. Lowering circulating thyroid hormones caused a significant increase in the response to con A that was prevented by hormone replacement. There was no effect on the response to PHA and raising circulating hormones had no effect on the responses to con A or PHA. It is suggested that stress-induced changes in thyroid hormones could modulate cell-mediated immune responses.

Animals↗

Cell mediated immune response of chicks following fowl adenovirus type-1 infection.

Cellular immune response of 6-week-old chickens infected with fowl adenovirus type-1 was evaluated by both in vivo and in vitro assay. In vitro assay, enumerating peripheral T lymphocyte by alphanaphthyl acetate esterase staining, revealed that cellular immunity appeared as early as 1 week post-infection and was maintained up to 5 weeks post-infection. In vivo assay by phytohaemagglutin skin test showed cellular immunity until 2 weeks post-infection. Thereafter no immunity was observed by this assay.

Adenoviridae Infections↗

Comparative studies on the antigenicity of extra- and intracellular viruses of fowl pox.

The intra- and extracellular virus of three strains of fowl pox virus, when precipitated in succession with different saturation of ammonium sulphate revealed three antigens in gel diffusion test in the precipitates obtained at 25%, 50% and 75% of saturation. Further analysis of each positive antigen by dot ELISA revealed that the extracellular virus of FS-8 and HP 1 strains possessed excess antigenic protein at 50% saturation compared to their intracellular viruses. While no difference between extra- and intracellular viruses of FS-4 strain was observed.

Animals↗

An improved dot ELISA to detect fowl adenovirus type-1 antigen.

An improved dot immunobinding assay to detect fowl adenovirus type-1 is described. The method consists of spotting of antigen on nitrocellulose membrane sheet, blocking with either 5% acetic acid or with 5% defatted milk powder and fixation of either antigen or antigen-antibody complex, with either 50% methanol or 0.25% glutaraldehyde or 0.2% tannic acid. The results revealed that fixation of both antigen and antigen-antibody complex resulted in 4-fold increase in sensitivity when acetic acid was used as blocking agent. The use of two substrates simultaneously resulted in more colour intensity and clarity than using both substrates separately.

Adenoviridae Infections↗

Calbindin, tyrosine hydroxylase and opioid-like immunoreactivity in the intestinal nerve of Remak of the domestic fowl.

Four classes of neurons were identified in both juxta-jejunal and juxta-rectal ganglia of Remak's nerve of the domestic fowl using double-labeling immunohistochemistry. Neurons immunoreactive (IR) for tyrosine hydroxylase (TH) formed a mutually exclusive subpopulation from neurons displaying calbindin (CaBP)-IR. Between 48-72% of juxta-jejunal neurons labeled for TH whereas 36-57% of juxta-rectal neurons displayed TH-IR. CaBP-IR was present in 18-40% of juxta-jejunal neurons; this increased to 31-46% in juxta-rectal neurons. The majority of CaBP-IR neurons (78-85%) also displayed opioid (beta-EP)-IR. Within each ganglion a small percentage of neurons (4-18%) were non-IR with any of the three antibodies. This is the first report of an immunohistochemically identified subpopulation of non-catecholaminergic neurons within the juxta-jejunal ganglia of Remak's nerve. It is proposed that these perikarya are a major source of the CaBP-IR and opioid-IR nerve fibers found in the chicken gut.

Animals↗

Growth of avian adeno-associated virus in chicken cells transfected with fowl adenovirus serotype 1 DNA.

Using the chloroquine-modified calcium phosphate coprecipitation technique, fowl adenovirus serotype 1 (FAV 1) DNA transfects efficiently chicken cell cultures. Infection of FAV 1 DNA transfected cells with helper dependent avian adeno-associated virus (AAAV) results in the production of AAAV progeny, being detected by an indirect immunofluorescence assay. These findings indicate that FAV 1 DNA introduced into the host cell promotes actively the growth of AAAV.

Adenoviridae Infections↗

Correlation between loss of the temperature-sensitive phenotype and pathogenicity of fowl plague virus mutants in the chicken.

The reversion of temperature-sensitive (ts) mutants of fowl plague virus to the ts+ phenotype was correlated with pathogenicity for chicken. Two types of ts mutants were investigated: those obtained by mutagenesis with 5-fluorouracil and those obtained by undiluted passages at 33 degrees C. The reversion frequency of the former mutants depended on the RNA segment in which the ts defect was located, mutations in RNA segments 1 and 2 having the highest reversion frequency, those in the RNA segments coding for the glycoproteins the lowest. ts mutants obtained by undiluted passages behaved differently in this respect. There was an approximate correlation between frequency of reversion and pathogenicity for chicken. Double mutants induced by 5-fluorouracil, having one tight and one leaky mutation, reverted easily without loss of the leaky mutation. These double mutants were still to a limited extent pathogenic for the chicken. Only one double mutant with two tight mutations (ts 293) was completely nonpathogenic after intramuscular inoculation. Two ts mutants with multiple tight defects (ts 1/1 and ts 3/18) obtained by undiluted passage did not revert to wild-type after injection into embryonated eggs and incubation at 33 degrees C, but they were still slightly pathogenic for the chicken. There was no obvious correlation between the shut-off temperature and pathogenicity of mutants carrying a single ts defect. However, for mutants with multiple tight mutations a high shut-off temperature seemed to be essential for reversion during serial passages as well as for pathogenicity in the chicken, when different routes of inoculation were examined. ts mutants seem to be safe as live vaccines only, (1) if they carry at least two tight ts defects, (2) if they have a relatively low shut-off temperature, and (3) if they could be administered other than via the respiratory tract.

Animals↗

Interaction of M protein and RNP of fowl plague virus in vitro.

The ability of the fowl plague virus (FPV) M protein to form a complex with FPV RNP and to inhibit the RNP transcriptase activity in vitro depended on NaCl concentration and did not depend on the concentration of nonionic detergents. The results obtained indicate that the M protein-RNP links formed were of an electrostatic rather than a hydrophobic nature. As demonstrated using individual RNP components, vRNA and RNA-free protein structures, M protein formed complexes only with vRNA, and the complex formation was salt-dependent. Analysis of products formed in the in vitro system containing RNP of FPV in the presence of the M protein showed impairment in the transcription of all RNA segments. The degree of inhibition correlated with the size of a segment, transcription of high molecular weight RNA segments being inhibited significantly more than that of low molecular weight RNA segments.

Animals↗

Temperature-sensitive mutants of fowl plague virus defective in the intracellular transport of the hemagglutinin.

Nine mutants of fowl plague virus with temperature-sensitive defects in the biosynthesis of the hemagglutinin have been characterized by analyzing the processing and the intracellular location of this glycoprotein in MDCK and chick embryo cells. It was found that with all of these mutants the transport of the hemagglutinin to the cell surface was impeded at the non-permissive temperature. There were differences, however, in the site of the block. With mutants tsl, ts227, ts478 and ts658 the precursor HA was not cleaved and the oligosaccharide side chains remained sensitive to endoglucosaminidase H. When the hemagglutinin was analyzed in permeabilized cells by immunofluorescence, usually only cytoplasmic labeling was seen. Immunofluorescence of non-permeabilized cells and hemadsorption revealed that the hemagglutinin did not reach the cell surface. In contrast, the hemagglutinin of mutants ts79, ts482, ts532, ts546 and ts651 was cleaved and oligosaccharides were processed to the endoglucosaminidase H-resistant form at non-permissive temperature. In permeabilized cells, the cytoplasm and juxtanuclear regions typical for the Golgi apparatus were labeled by immunofluorescence. Except for ts482, ts532 and ts546 which were leaky, hemagglutinin could not be detected at the cell surface. These observations indicate that, with the first group of mutants, hemagglutinin transport is usually arrested already in the rough endoplasmic reticulum, whereas with the second group it is inhibited at a late stage between the Golgi apparatus and the plasma membrane.

Animals↗

Construction of an aroA mutant of Salmonella serotype Gallinarum: its effectiveness in immunization against experimental fowl typhoid.

An aroA mutant was produced from a virulent strain of Salmonella Gallinarum, the causative agent of fowl typhoid in poultry, by Tn10 insertional inactivation and deletion. The mutant was highly attenuated for chickens. A single intramuscular immunization of 2-week-old chickens with 10(7) mutant organisms reduced mortality following oral challenge with 10(8) organisms of the parent strain from 63 to 30%. In a second experiment multiple immunizations with 10(8) mutant organisms reduced mortality after challenge with 10(7) organisms of the virulent strain from 77 to 0%. By oral inoculation the mutant was not able to immunize chickens against oral challenge.

Animals↗

Oxygen uptake in fowl eggs incubated in air and pure oxygen.

1. The oxygen uptake of small (bantam hen) and large (white leghorn) domestic fowl eggs was measured during incubation in air and pure O2. 2. A 2 hr exposure to pure O2 increased the O2-uptake from the 9th day in the large eggs and from the 15th day in the small eggs. 3. On the last 4 days of the incubation period, both small and large eggs increased their O2-uptake by about 22% when transferred from air to pure O2. 4. When 1 cm2 of the eggshell above the air cell was removed, the O2-uptake of the white leghorn eggs incubated in air increased by 13%.

Aerobiosis↗

Acid-base regulation during thermal panting in the fowl (Gallus domesticus): comparison between breeds.

1. The effects of high ambient temperatures on blood acid base status were studied in four breeds of fowl. 2. All breeds efficiently regulated body temperature below ambient temperature at 45 degrees C (Tb = 38.521 + 0.110Ta, at 25-45 degrees C). 3. A slight hypocapnia was partly compensated for by a decreased HCO3 concentration. This resulted in only a slight respiratory alkalosis at extreme temperatures (+0.021 and +0.042 pH units at 42 and 45 degrees C, respectively). 4. Changes in Paco2 were negatively correlated with tidal volume: Paco2 (torr) = 33.10390 - 1.17493 VT(ml); r = -0.925, P much less than 0.001. 5. The present findings are consistent with an hypothesis that modulation of tidal volume during thermal panting might play a major role in acid-base regulation.

Acid-Base Equilibrium↗

Cell membrane amino acid transport processes in the domestic fowl (Gallus domesticus).

Intestinal absorption of amino acids in the chicken occurs by way of processes which are concentrative, Na+-dependent and dependent upon metabolic energy in the form of ATP. Intestinal transport is carrier-mediated, subject to exchange transport (trans-membrane effects) and is inhibitable by sugars, reagents which inactivate sulfhydryl groups, potassium ion, and by deoxpyridoxine, an anti-vitamin B6 agent. It is stimulated by phlorizin, a potent inhibitor of sugar transport, and in Na+-leached tissue by modifiers of tissue cyclic AMP levels, e.g. theophylline, histamine, carbachol and secretin. Separate transport sites with broad, overlapping specificities function in the intestinal absorption of the various classes of common amino acids. A simple model for these sites includes one for leucine and other neutral amino acids, one for proline, beta-alanine and related imino and amino acids, one for basic amino acids, and one for acidic amino acids. Absorption of amino acids appears to be widespread in occurrence in the digestive tract of the domestic fowl; transport has been reported to be present in the crop, gizzard, proventriculus, small intestine and in the colon. By the end of the first week of life post-hatch, the caecum loses its ability to transport. Similarly, the yolk sac loses its ability by the second day post-hatch. Intestinal transport was noted before hatch and was found to be maximal immediately post-hatch. A requirement for Ca2+ appears to be lost after the first week of life post-hatch. The cationic amino acids appear to be reabsorbed by a common mechanism in the kidney. Transport rates of leucine measured in the intestine or in the erythrocyte were found to cluster about discrete values when many individual chickens were surveyed; such patterns may be an expression of gene differences between individuals. Two lines of chickens have been developed, one high and the other low uptake, through selective breeding based on the ability of individual birds to absorb leucine in erythrocytes. High leucine absorbing chickens were found to be more effective in absorbing lysine and glycine, were more effectively stimulated by Na+, had greater erythrocyte Na+, K+-ATPase activity, and their erythrocytes contained about 20% less Na+ than low line erythrocytes. The underlying genetic difference between these lines may reside at the level of the Na+, K+-ATPase and (or) with a regulatory gene determining carrier copies. Amino acid transport in erythrocytes was noted to be highest in pre-hatch chicks and to diminish during post-hatch development.(ABSTRACT TRUNCATED AT 400 WORDS)

Absorption↗

Relation between Ca2+ uptake and ATPase activity in the particulate fractions of the eggshell gland mucosa of the domestic fowl and duck.

The relation between the rates of ATP-dependent Ca2+ uptake and ATP hydrolysis was studied in homogenates of eggshell gland mucosa and its subcellular fractions from the domestic fowl and duck. The Ca2+-Mg2+-ATPase activity was 5-10% of that of the "basal" Mg2+-ATPase at an optimal Ca2+ concentration in the subfractions. The presence of K+ and/or Na+ increased the rate of Ca2+ uptake and the Ca2+-Mg2+-ATPase activity; the effects of K+-Na+ were not inhibited by ouabain. The Ca/P ratio varied with the experimental conditions. At 10(-4) M Ca2+ and in the absence of K+ Na+ it was 0.8, and in their presence 0.4.

Adenosine Triphosphatases↗

The effects of ACTH and dexamethasone upon plasma thyroid hormone levels and heat production in the domestic fowl.

Treatment with long acting ACTH (20 IU kg-1) produces a large and sustained elevation of plasma corticosterone in the domestic fowl. Both ACTH treatment and administration of dexamethasone produce significant reductions in plasma concentrations of T4 and T3, and these changes are accompanied by a sustained hyperglycaemia. Despite the changes in circulating thyroid hormones only a small reduction in heat production (-14%) was induced by either treatment and mainly during the dark period. Whilst there may be some causal relationship between increased corticosterone secretion, decreased plasma thyroid hormone levels and reduced metabolic heat production it is unlikely that these responses alone account for the adjustments in energy expenditure observed in short term food deprivation.

Adrenocorticotropic Hormone↗