References
- Bowman , J. C. and Challender , N. I. 1963 . Egg shell strength. A comparison of two laboratory tests and field results . Br. Poult. Sci. , 4 : 103 – 116 .
- Frank , F. R. , Swanson , M. H. and Burger , R. E. 1964 . The relationship between selected physical characteristics and the resistance to shell failure of Gallus domesticus eggs . Poult. Sci. , 43 : 1228 – 1235 .
- Gaisford , M. J. 1965 . The application of shell strength measurements in egg shell quality determinations . Br. Poult. Sci. , 6 : 193 – 196 .
- Hurwitz , S. and Griminger , P. 1962 . Egg produc‐tion and shell quality in temperature and light controlled versus uncontrolled environment . Poult. Sci. , 41 : 499 – 508 .
- Jenkins , N. K. and Tyler , C. 1960 . Changes in egg shell thickness and white and yolk weight and composition over a period of a year . J. agric. Sci., Camb. , 55 : 323 – 331 .
- McNally , E. H. 1965 . The relationship of egg shell weight to cracked eggs . Poult. Sci. , 44 : 1513 – 1518 .
- Mueller , C. D. and Scott , H. M. 1940 . The porosity of eggshell in relation to hatchability . Poult. Sci. , 19 : 163 – 166 .
- Schoorl , P. and Boersma , H. Y. . Research on the quality of the egg shell. A new method of determination . 12th Wld's Poult. Congr. . Sydney. pp. 432 – 435 .
- Sluka , S. J. , Besch , E. L. and Smith , A. H. 1965 . A hydrostatic tester of egg shell strength . Poult. Sci. , 44 : 1494 – 1500 .
- Snedecor , G. W. 1956 . Statistical methods , Ames : Iowa State College Press .
- Tyler , C. 1961 . Shell strength: its measurement and its relationship to other factors . Br. Poult. Sci. , 2 : 3 – 18 .
- Tyler , C. and Coundon , J. R. 1965 . Apparatus for measuring shell strength by crushing, piercing or snapping . Br. Poult. Sci. , 6 : 327 – 330 .
- Tyler , C. and Geake , F. H. 1953 . Studies on egg shells. III. Some physical and chemical characteristics of egg shells of domestic hens . J. Sci. Fd Agric. , 4 : 587 – 596 .
- Tyler , C. and Geake , F. H. 1958 . Studies on egg shells. IX. The influence of individuality, breed and season on certain characteristics of egg shells from pullets . J. Sci. Fd Agric. , 9 : 473 – 483 .
- Tyler , C. and Geake , F. H. 1960 . Studies on egg shells. XIII. Influence of individuality, breed, season and age on certain characteristics of egg shells . J. Sci. Fd Agric. , 11 : 535 – 547 .
- Tyler , C. and Geake , F. H. 1961 . Studies on egg shells. XV. Critical appraisal of various methods of assessing shell thickness . J. Sci. Fd Agric. , 12 : 281 – 289 .
- Tyler , C. and Geake , F. H. 1963 . A study of various impact and crushing methods used for measuring shell strength . Br. Poult. Sci. , 4 : 49 – 61 .
- Tyler , C. and Geake , F. H. 1964a . The testing of methods of cracking egg shells, based on paired readings from individual eggs and the measurement of some effects of various treatments . Br. Poult. Sci. , 5 : 19 – 28 .
- Tyler , C. and Geake , F. H. 1964b . The testing of methods of crushing egg shells, based on paired readings from individual eggs and the measurement of some effects of various treatments . Br. Poult. Sci. , 5 : 29 – 35 .
- Tyler , C. and Geake , F. H. 1964c . A direct comparison of certain cracking and crushing methods used for measuring shell strength . Br. Poult. Sci. , 5 : 37 – 43 .
- Present address: British Egg Marketing Board Experimental Unit, Edgmond, Newport, Shropshire.