Genetic selection to increase bone strength affects prevalence of keel bone damage and egg parameters in commercially housed laying hens.

The prevalence of keel bone damage as well as external egg parameters of 2 pure lines divergently selected for high (H) and low (L) bone strength were investigated in 2 aviary systems under commercial conditions. A standard LSL hybrid was used as a reference group. Birds were kept mixed per genetic line (77 hens of the H and L line and 201 or 206 hens of the LSL line, respectively, per pen) in 8 pens of 2 aviary systems differing in design. Keel bone status and body mass of 20 focal hens per line and pen were assessed at 17, 18, 23, 30, 36, 43, 52, and 63 wk of age. External egg parameters (i.e., egg mass, eggshell breaking strength, thickness, and mass) were measured using 10 eggs per line at both 38 and 57 wk of age. Body parameters (i.e. tarsus and third primary wing feather length to calculate index of wing loading) were recorded at 38 wk of age and mortality per genetic line throughout the laying cycle. Bone mineral density (BMD) of 15 keel bones per genetic line was measured after slaughter to confirm assignment of the experimental lines. We found a greater BMD in the H compared with the L and LSL lines. Fewer keel bone fractures and deviations, a poorer external egg quality, as well as a lower index of wing loading were found in the H compared with the L line. Mortality was lower and production parameters (e.g., laying performance) were higher in the LSL line compared with the 2 experimental lines. Aviary design affected prevalence of keel bone damage, body mass, and mortality. We conclude that selection of specific bone traits associated with bone strength as well as the related differences in body morphology (i.e., lower index of wing loading) have potential to reduce keel bone damage in commercial settings. Also, the housing environment (i.e., aviary design) may have additive effects.

Elegant arts for ladies : comprising ...

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The Cambridge natural history,

Vols. 1, 2, 5-7, 9 reprinted 1922; v. 3, 1927; and vols. 4, 8, 10, 1923.

Cavies: their varieties, breeding and management.

Mode of access: Internet.

Monographie der arktischen Acariden /

Blank leaves bound between each leaf.

Coleccion completa de los tratados, convenciones, capitulaciones, armisticios y otros actos diplomáticos : de todos los estados de la América Latina : comprendidos entre el golfo de Méjico y el cabo de Hornos : desde el año de 1493 hasta nuestros dias ... /

Includes indexes.

Acarologists of the world: a directory.

Issued by the National Institutes of Health, Rocky Mountain Laboratory, Hamilton, Mont. and the Department of Zoology, University of Oklahoma.

[Mite reprints: General.]

Made-up set; supplied title.

Guatemala-Honduras boundary arbitration; reply of Guatemala to the counter case of Honduras submitted to the Arbitral tribunal composed of: the Hon. Charles Evans Hughes, chief justice of the United States of America; Hon. Luis Castro Ureña, from Costa Rica; Hon. Emilio Bello Codesdido, from Chile. Under treaty of July 16, 1930.

"Annex number 189. Report relating to the construction of the hypsometric map of the republic of Guatemala drawn under the supervision of the engineering staff of the Guatemala boundary commission, by order of the government of the republic": p. 178-183. Signed: Guatemala, September 29, 1928. Claudio Urrutia.

Studien an Acariden. /

Mode of access: Internet.

Collected edition.

Vol. 1 contains music.

Zur Morphologie und Ontogenie der Acariden.

Mode of access: Internet.

The works of Douglas Jerrold.

I. Introductory memoir. St. Giles and St. James. Punch's letters to his son.--II. The story of a feather. Cakes and ale.--III. Mrs. Caudle's curtain lectures. Men of character. Punch's complete letter writer.--IV. A man made of money. Sketches of the English. The chronicles of Clovernook. The sick giant and the doctor dwarf.

The air sac mite of the fowl.

Reprinted from: American Veterinary Review, 1898, v. 22, p. 3-25.

Indian museum notes.

CONTENTS.--vol. I, no. 1. Notes on Indian insect pests. 1889. no. 2. Notes on Indian economic entomology. 1889. no. 3. Silkworms in India. 1890. no. 4. Notes on Indian economic entomology. 1890.--vol. II, no. 1. Economic entomology. 1891. no. 2. The wild silk insects of India. 1891. no. 3. On white insect wax in India. 1891. no. 4. The locusts of Bengal, Madras, Assam, and Bombay. 1891. no. 5. [Economic entomology, etc.] 1891. no. 6. A conspectus of the insects which affect crops in India. 1893.--vol. III, no. 1-3. [Notes on Indian insect pests, etc.] 1893-94. no. 4. An account of the insects and mites which attack the tea plant in India. 1895. no. 5-6. [Entomological notes] 1894-96.--vol. IV-vol. VI, no. 1. [Notes on Indian insect pests] 1896-1903.