Genetics of Reproduction in Sheep

I Genetic Variation and Selection


1 Selection for Litter Size


2 Crossbreeding for Fecundity


3 Evaluation and Utilization of Finn Sheep


4 The Performance of Romanov Crosses and Their Merits as a Basis for Selection


5 Genetic Studies of Reproduction in Norwegian Sheep


6 Crossbreeding for Fecundity in Subtropical Sheep


7 The Fecundity of the Chios Sheep


8 Prolific Breeds of Goat


9 Reproductive Physiology in South American Camelids


10 Genetic and Maternal Effects on Sheep Reproduction and Their Influence on Selection


11 Improvement of Reproductive Performances in Rasa Aragonesa. Present Results in Selection and Crossbreeding Experiments


12 The Preliminary Results of Selection for Prolificacy in Polish Merino Sheep

II The Inheritance and Effects of the Booroola Gene


13 The Single Gene Inheritance of the High Litter Size of the Booroola Merino


14 The Productivity of Bungaree, Booroola X Bungaree and Trangie Fertility X Bungaree Merino Ewes in South Australia


15 Introduction and Management of the Booroola Gene in Sheep Flocks in New Zealand

III Genetic Strategies for Single Genes


16 Utilization of Major Genes


17 Single Genes for Fecundity in Icelandic Sheep


18 Principles and Practice for the Use of the Booroola Merino in Extensive Husbandry


19 Linear Programming Model for Incorporating the Booroola Gene into Another Breed

IV Physiology of Genetic Variation


20 Breed Differences in Ovulation Rate and Uterine Efficiency and Their Contribution to Fecundity


21 Contribution of Variation in Ovulation Rate and Embryo Survival to within Breed Variation in Litter Size


22 The Mechanism of Action of Genes Controlling Reproduction


23 Reproductive Endocrinology of Prolific Sheep: Studies of the Booroola Merino


24 Ovulation Rate and Oestrus in Booroola Genotypes: Some Effects of Age, Season and Nutrition


25 Sexual and Ovarian Function of the D'man Ewe


26 Folliculogenesis in Sheep: Control of Ovulation Rate


27 Physiological Criteria for Embryo Mortality: Is Asynchrony Between Embryo and Ewe a Significant Factor?


28 Physiological Criteria in Genetic Selection for Aseasonality


29 Parameters of Male Fertility and Their Genetic Variation in Sheep


30 FSH Plasma Levels in Male and Female Lambs Issued from Lacaune Rams with High or Low Prolificacy Index

V Physiological Criteria of Genetic Merit


31 Detection and Genetic Assessment of Physiological Criteria of Merit Within Breeds


32 Testis Size and LH Response to LH-RH as Male Criteria of Female Reproductive Performance


33 Heritabilities of Testis Size and Sexual Behavior in Males and Their Genetic Correlations with Measures of Female Reproduction

VI Nutritional Requirements and Systems of Husbandry


34 Protein, Energy and Ovulation Rate


35 Nutritional Requirements of the Pregnant and Lactating Ewe


36 The Possibilities for Improving the Performance of Ewes Suckling Three or More Lambs in Grazing Systems


37 The Utilization of Romanov Sheep in a System of Integrated Husbandry


38 Productivity of Booroola Cross Merinos in Western Australia


39 Intensive Husbandry of Fecund Sheep

Index