Incubation

TH E artificial incubation of eggs is not a recent innovation. For many centuries, some species of birds—our mallee-hen being a typical example—have hatched out their eggs by the heat generated in mounds of decaying vegetation.Furthermore, they have shown considerable skill in maintaining the mounds at uniform temperatures throughout the hatching period. A number of reptiles employ similar methods to hatch their eggs, although in these instances there does not seem to be the same need for carefully-controlled temperature

Chronic respiratory disease of poultry in Western Australia

Widespread chronic respiratory disease was revealed in a survey of respiratory infections in Perth metropolitan area poultry flocks. Most occur in early or midsummer and cause a serious fall in egg production. Return to full lay after the infection is usually slow. While these infections can cause production losses in flocks which are under heavy stress, none of the more serious forms of chronic respiratory disease was found. This gives encouragement for future control of the disease in Western Australia

Incubation

TH E artificial incubation of eggs is not a recent innovation. For many centuries, some species of birds—our mallee-hen being a typical example—have hatched out their eggs by the heat generated in mounds of decaying vegetation.Furthermore, they have shown considerable skill in maintaining the mounds at uniform temperatures throughout the hatching period. A number of reptiles employ similar methods to hatch their eggs, although in these instances there does not seem to be the same need for carefully-controlled temperature

Chronic respiratory disease of poultry in Western Australia

Widespread chronic respiratory disease was revealed in a survey of respiratory infections in Perth metropolitan area poultry flocks. Most occur in early or midsummer and cause a serious fall in egg production. Return to full lay after the infection is usually slow. While these infections can cause production losses in flocks which are under heavy stress, none of the more serious forms of chronic respiratory disease was found. This gives encouragement for future control of the disease in Western Australia

Strategies to exploit genetic variation while maintaining diversity

How we should manage genetic diversity depends on why we want to manage it. The most generally useful strategy is to maintain variation across the genome, using methods that consider one or more of: population size, population structure, animal selections, mate allocations and information from genetic markers. A key reason to maintain genetic diversity is to facilitate longer-term genetic gains, and this means that most breeding programs need to consider genetic diversity as well as shorter-term genetic gains. This paper discusses these issues, and presents developments in methods to integrate genetic gains, genetic diversity and other issues within breeding programs