Black-capped Chickadees (Poecile atricapillus) can identify individual females by their fee-bee songs

Individual recognition is a social behavior that occurs in many bird species. A bird’s ability to discriminate among familiar and unfamiliar conspecifics is critical to avoid wasting resources such as time and energy during social interactions. Black-capped Chickadees (Poecile atricapillus) are able to discriminate individual female and male chick-a-dee calls, potentially male and female tseet calls, and male fee-bee songs. In the current study, we used an operant discrimination go/no-go paradigm to determine whether female and male chickadees could discriminate between fee-bee songs produced by individual female chickadees as well as test which song component(s) enable this discrimination. Birds trained on natural categories—the songs of different females—learned to respond to rewarded stimuli more quickly than birds trained on random groupings of female songs and were able to transfer this learning to new songs from the same categories. Chickadees were also able to generalize their responding when exposed to the bee note of the fee-bee song of rewarded individuals; they did not generalize to fee notes. Our results provide evidence that Black-capped Chickadees can use female-produced fee-bee songs for individual recognition. However, the acoustic features underlying individual recognition require further investigation.

Chick growth and nutrient requirement during rearing period on eclectus parrot (Eclectus roratus, Müller 1776)

Nutrition is an important aspect of the successful breeding of wild birds in captivity. This research aims to find out nestling growth of Eclectus parrot (Eclectus roratus, Müller 1776) by parent-reared and nutrient requirement during rearing season. This research used a pair of Eclectus parrot with a male chick at first and fifth clutch, and female chick at the second, third, and fourth clutch. This research was conducted from July 2016 to June 2018. The bodyweight of chick was measured every week and feed intake was observed since the age of one week until the chick can eat independently. Feed was provided ad libitum and cafeteria. The chick was the altricial type. Feathers began to cover all bodies at weeks 9. Fledging time was approximately at weeks 10-11. Chick could be separated from its parents at 20 weeks of age. Feed intake tends to be increased along with the increasing age of chick. Eclectus favorites feed is sunflower seed. Nutrient consumption when rearing male chick is more than rearing the female chick.

An ovomucin-like protein on the surface of migrating primordial germ cells of the chick and rat

A mucin was discovered on the surface of migratory primordial germ cells (PGCs) from chick and rat embryos by means of two monoclonal antibodies. The protein was found to be identical or closely related to ovomucin, a 600 X 10(3) relative molecular mass glycoprotein, and a major constituent of the vitelline membrane of the avian yolk. Based on its resemblance to ovomucin it is referred to as ovomucin-like protein (OLP). The OLP was expressed on PGCs from E3 to E7 female, and from E3 to E12 male chick embryos as the PGCs migrate and colonize the gonadal ridges. After the PGCs have settled in the gonads, they no longer express OLP. In tissue cultures of dissociated cells from E6 gonads, OLP was present only on cells that were positive for PAS staining, the standard histological method to identify PGCs in the chick embryo. Since unfixed PGCs were recognized by the antibodies, at least part of the OLP is localized on the cell surface. The anti-OLP antibodies also stained PGCs in the gonads of the rat embryo, showing that the expression of this antigen on PGCs is phylogenetically conserved. Ovomucin isolated from vitelline membrane prevented adhesion of fibroblasts but not PGCs when used a as a substratum in vitro. The anti-adhesive quality of the mucin resides in the sialic acid residues of the carbohydrate side chains. We propose that OLP has a similar anti-adhesive quality as the ovomucin from vitelline membrane, and that this anti-adhesive property is important to prevent precocious adhesion of migrating PGCs to blood vessel walls and to connective tissue in the mesentery as they migrate toward the gonadal ridges.

The fate of female donor blastodermal cells in male chimeric chickens

In previous experiments in our laboratories, chickens that are chimeric in their gamete, melanocyte, and blood cell populations have been produced by injection of dispersed stage X blastodermal donor cells into the subgerminal cavity of stage X recipient embryos. In some experiments, donor cells were transfected with reporter gene constructs prior to injection as a preliminary step in the production of transgenic birds. Chimerism was assessed by test mating, observation of plumage, and DNA fingerprinting. Methods were sought that would provide a relatively rapid analysis of the spatial distribution of descendants of donor cells in chimeras to assess the efficacy of various methods of chimera construction. To date, the sex of donor and recipient embryos was not known and, therefore, numerous mixed sex chimeras must have been constructed by chance, since donor cells were usually collected from several embryos rather than from individual embryos. The presence of female-derived cells was determined by in situ hybridization using a W-chromosome-specific DNA probe, using smears of washed erythrocytes from 16 phenotypically male chimeric chickens ranging in age from 4 days to 42 months posthatching. The proportion of female cells detected in the erythrocyte samples was zero (eight samples) or very low (0.020–0.083%), although 1% of the erythrocytes from a phenotypically male chick that was killed 4 days after hatch were female-derived. The low proportions of female-derived cells were surprising, considering that most of these chimeras had been produced by the injection of cells pooled from several donor embryos and most recipients had been exposed to γ irradiation prior to injection, thus dramatically enhancing the level of incorporation of donor cells into the resulting chimeras. By contrast, 0–100% of the erythrocytes were female-derived in blood samples taken at 10 days of incubation from the chorioallantois of seven phenotypically normal male embryos that resulted from the injection of blastodermal cells pooled from five embryos into irradiated recipient embryos. Approximately 70% of the erythrocytes in a blood sample from a phenotypically normal female chimeric embryo were female-derived, and 100% of the erythrocytes examined from an intersex embryo bearing a right testis and a left ovary were female-derived. These results indicate that female-derived cells can contribute to the formation of erythropoietic tissue during the early development of what will become a phenotypically male chimeric embryo. It would appear, therefore, that female-derived cells are blocked in development or destroyed, or certain male–female combinations of cells may be lethal prior to hatching. In future, chimeras will be produced from individual donors, or pools will be made of either male or female donor cells identified by in situ hybridization of smears of dispersed blastodermal cells using the W-chromosome-specific probe.Key words: chimera, chicken, W chromosome, in situ hybridization, transgenic.

PERFORMANCE OF LEGHORN PULLETS AND LAYING HENS IN RELATION TO HATCHING EGG SIZE

In trial 1, eggs from young (28 wk) and old (65 wk) leghorn breeders were categorized into groups with mean weights of 54, 59 or 64 g. Female chicks were cage-reared to 18 wk of age; three rearing treatments involved five replicate cages of nine pullets from each egg size category, while treatment 4 involved a mixed population. The largest eggs contained most yolk fat and protein and albumen protein (P < 0.05). Egg size had no effect on male chick composition (P < 0.05). There was no overall effect of egg size or breeder age on feed intake of pullets, although up to 8 wk of age, pullets from small eggs were consistently smaller than those from large eggs. Egg size and breeder flock age had no effect on pullet weight at 18 wk. Pullets reared as a combination group of small:medium:large (3:3:3, treatment 4) showed a significant (P < 0.05) egg size effect on pullet weight at 18 wk of age. In a second trial, eggs were collected from a 45-wk-old flock of commercial leghorn breeders. Eggs were set according to weight, with mean egg weights of 56.4, 61.1 or 66.8 g. Rearing treatments related to the three egg size categories were represented by 10 replicate groups of nine birds each. A fourth treatment involved 26 groups of three chicks from each of the egg weight treatments. Breeder egg size had a significant effect on pullet weight at 126 d. With this differential maintained through the first 12 wk of lay. Breeder egg size had no effect on egg production (P > 0.05), although mean commercial egg weight and feed intake (P < 0.01) were directly proportional to hatching egg size (P < 0.01). It is concluded that hatching egg size can have a significant effect on life-cycle performance of leghorns, and as such, there may be scope for differential management of pullets hatched from different sizes of egg. Key words: Pullet, egg size, egg composition