A role for endogenous opiates in incubation behavior in ring neck doves (Streptopelia risoria)

The Physiology of the Formation of "Pigeon's Milk"

Successful reproduction in avian species requires considerable parental care, and for most species the efforts of both parents are necessary for the survival of offspring. Here we make the case that in these species reproductive interactions are enhanced when neurochemical activity reinforces critical stimuli and behaviors through associative learning. Drawing from research on several different species, we describe evidence for the role of associative learning in the reproductive behaviors of ring neck doves (Streptopelia risoria). A hypothetical mechanism involving a combination of classical and operant conditioning is proposed to explain the formation and maintenance of the pair bond, nest fidelity, and incubation behavior. The role of the opiate system in reinforcing various aspects of reproductive behavior in this and other species is discussed.

The relationship of hormones to the reproductive behaviour of birds, referring especially to parental behaviour: A review

Humoral response to Mycobacterium avium subsp. avium in naturally infected ring-neck doves ( Streptopelia risoria)

The Role of Prolactin in Parental Care in a Monogamous and a Polyandrous Shorebird

In avian brood parasitism, parasites lay their eggs in the nests of hosts, and many hosts in the wild respond by eliminating or abandoning foreign eggs in their clutch. However, a limitation upon the study of proximate, especially physiological and experience-dependent cognitive mechanisms of egg rejection, has been the lack of a suitable model system in captivity. Here, we tested whether laboratory-kept ringneck doves (Streptopelia risoria) respond to visually distinct egg types (through applying an ink treatment upon the doves' own eggs) by rejecting them. We found that in two of two experiments, brown eggs were more often rejected, through predominantly egg burial, relative to control eggs but were done so only by a subset of dove pairs. These results are supportive of ringneck doves to become a suitable captive model for the study of foreign-egg rejection, and open the way for future research on the integrative (e.g., genetic, endocrine, ontogenetic, and cognitive) study of egg-rejection responses in a tractable research system. However, the ecological validity and applicability of this model system for the analysis of host-parasite interactions in the wild remain narrowly limited. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Passive immunization against chicken vasoactive intestinal polypeptide suppresses plasma prolactin and crop sac development in incubating ring doves

Residue data is presented from shell thinning studies in Ring Neck Doves (Streptopelia risoria) fed 33 mg/kg, or 10 mg/kgp,p′ dicofol or the dicofol metabolite 1,1-bis(4-chlorophenyl)2,2 dichloroethanol (p,p′ DCD) at 10 and 32 mg/kg for approximately 90 days. The metabolism and storage of dicofol and dicofol metabolites in breeding females is examined. Concentrations ofp,p′ dicofol, DCDp,p′ dichlorobenzophenone (p,p′ DCBP),p,p′ dichlorobenzydrol (p,p′ DCBH), and 1,1-bis(4-chlorophenyl)-2,2 dichloroethylene (p,p′ DDE) were determined in liver, fat, heart, brain, oviduct and yolk of doves. The major metabolite was DCD. Doves exposed to DCD alone did not produce thinned eggshells at either dose. DCD was poorly metabolized by doves to DCBP and DCBH. DDE was present but in concentrations far below other OCs and was not a metabolite of dicofol. Doves had two metabolic routes for transforming dicofol to more water soluble metabolites, reduction to DCD and oxidation to DCBP with subsequent formation of DCBH. The formation of DCBH was limited by the rate of DCBP formation. Yolk residues of DCBP indicated individual doves varied in their ability to produce DCBP. DCBP accumulation in yolk over time was correlated with individual doves' eggshell thinning response over time of treatment. Doves with low rates of DCBP accumulation in yolk had greater declines in shell thickness per day of dicofol treatment. It is concluded that the dicofol metabolites DCD, DCBP, and DCBH are less toxic than dicofol to eggshell formation in ring neck doves.

During the breeding season, monogamous birds form partnerships characterized by preferential involvement in reproductive and parental behaviors with a mate. The breeding partnership is dependent on a ‘pair bond’, an adhesive force that promotes prolonged affiliation and behavioral cooperation between two birds. Here we propose that the adhesive force of the pair bond is at least partially the result of the acquired reinforcement value of the mate. If the mate becomes a reinforcer during courtship then through classical conditioning principles the mate will reinforce affiliative behavior evident in pair-bonded birds. The present experiments were designed to determine whether the pair-bonded mate of ring neck dove (Streptopelia risoria) acquire reinforcement value during the reproductive cycle. Mate reinforcement value was assessed using a conditioned place preference paradigm in which the mate was paired with a visually distinct context and a second distinct context was paired with social isolation (Experiment 1) or an unfamiliar bird of the opposite sex (Experiment 2). Both males and females preferred the context that had been paired with the mate to the context paired with social isolation or an unfamiliar dove. The results suggest that pair-bonded mates are stronger reinforcers than unfamiliar birds. Experiment 3 found that the preference for the mate context over the unfamiliar dove context was stronger during incubation than during courtship. The possible involvement of a classical conditioning process in the maintenance of the pair bond is discussed.

Opioid Peptides and Long-term Potentiation in the Hippocampus

The present experiments were designed to determine whether blockade of endogenous opiate receptors with naloxone would suppress renin release induced by circulating epinephrine or by reductions of renal perfusion pressure. In the first series of experiments, anesthetized dogs were prepared with a flow probe around the left renal artery and a catheter in the left renal vein, permitting measurement of renin secretion before, during, and after 15-min infusions of epinephrine (50 ng.kg-1.min-1 iv). The epinephrine infusions were conducted either before or after blockade of opiate receptors with naloxone (1 mg/kg iv). Naloxone failed to alter the renin secretory response to intravenous epinephrine infusion. In a second series of experiments, anesthetized dogs were uninephrectomized and prepared with a constrictor cuff around the left renal artery and a renal arterial catheter distal to the cuff. After control measurements of renal perfusion pressure and plasma renin activity (PRA), the cuff was constricted at 15-min intervals to produce controlled stepwise reductions of renal perfusion pressure ranging from 15 to 90 mmHg. One-half of the animals was pretreated with naloxone (1 mg/kg iv). Naloxone pretreatment had no effect on the PRA response to reduced renal perfusion pressure at any pressure. The data fail to support the hypothesis that endogenous opioid peptides are modulators in the control of renin release.

Even when different diagnostic modalities are available, mycobacteriosis is difficult to diagnose in a live bird. To investigate the diagnostic value of sampling different tissues and using different diagnostic methods, we evaluated results of mycobacterial culture, Ziehl-Neelsen (ZN) staining, and single-amplification polymerase chain reaction assay (PCR) of 18 ring-neck doves (Streptopelia risoria) with confirmed natural infection with Mycobacterium avium avium. Results of testing liver biopsy, duodenal aspirate, and bone marrow aspirate samples and liver and spleen samples collected at necropsy were compared. Results showed the use of one single technique did not allow identification of all infected birds. In liver biopsy and bone marrow aspirate samples, culture had the highest sensitivity, whereas PCR assay and ZN staining had low sensitivity, and their combination was less sensitive than culture alone. Examination of ZN staining of the intestinal aspirate samples failed to detect infection in most birds. More splenic lesions contained acid-fast organisms than did liver lesions, suggesting that splenic biopsy may have the greatest potential for diagnosis of mycobacterial infection antemortem. Sensitivity was higher for postmortem examination of multiple liver sections than of a single biopsy section; therefore, obtaining multiple liver biopsy sections may increase detection of mycobacteria. Examination of multiple tissues and the use of several different diagnostic techniques significantly increases the probability of diagnosis of mycobacteriosis.

Ceftiofur crystalline free acid (CCFA) is a third-generation, oil-based, cephalosporin antimicrobial marketed as a once weekly treatment in cattle and swine, and as a two-time dose with 10-day duration in horses. Because handling and restraint times can be reduced, long-acting antibiotic preparations are particularly useful for treatment of nondomestic species. This study evaluated the pharmacokinetics of CCFA in ringneck doves (Streptopelia risoria). A single intramuscular (IM) injection of CCFA at 50 mg/kg was administered to each of 30 doves, and blood was collected from subsamples of 6 birds at predetermined sampling times (i.e., with a postinjection range of 0.5 to 192 hr). All ringneck doves were scheduled for euthanasia because of reasons unrelated to the study; this was performed at the conclusion of the study; and complete postmortem and histopathologic examinations were performed. Plasma concentrations of CCFA remained above the minimum inhibitory concentration (1.0 µg/ml; observed for most avian pathogenic bacteria) for 108 hr. No abnormalities were identified on individual birds before and after clinical pathology results (i.e., hematocrits and plasma biochemistry profiles), and only minimal gross and histopathologic changes such as mild tissue inflammation at the injection site were observed. Based on these results, one IM injection of CCFA at 50 mg/kg seems to be a potential option for treatment of ringneck doves.

Prevalence of infection and disease, the degree of organ involvement and the nature of the lesions were investigated in 11 white and 18 non-white ring-neck doves coming from a flock naturally infected with Mycobacterium avium subsp. avium. Lesions were common in the liver, spleen, lung, kidney, intestines, ovary and bone marrow. Overall, 18 out of 29 (62%) birds were considered infected with a sequevar of M. avium subsp. avium that contains serotypes 2, 3, 4 and 9. The prevalence of infection in the white doves (36.4%) was significantly lower than in the non-white morphs (77.7%). White doves had on average fewer organs affected (mean =3.1) than the non-white doves (mean =5.9). A diffuse pattern of inflammation in the liver and spleen was observed mainly in non-white doves. Focal or multifocal granulomatous inflammation of the liver and spleen was predominant in white doves. Genetic mechanisms of immunity to mycobacteriosis may be contributing or determining these differences. There are three basic colour morphs in ring-neck doves—dark or wild type, blond and white—and the alleles coding for colour are sex-linked and located on the sex (Z) chromosome. Female's single sexual chromosomed (ZW) and homozygous males (ZZ) can be white if they carry the white alleles. It is very probable that the gene or genes modulating the immune response to M. avium subsp. avium infection in these doves could be associated to these loci or at least located in the same (Z) chromosome, as the association with white colour suggests.

Situational and hormonal determinants of courtship, aggressive and incubation behavior in male ring doves ( Streptopelia risoria)