Wendy Muir

I. INTRODUCTIONProduction improvements in commercial meat chickens via genetic selection and improved husbandry have resulted in rapid growing birds. These birds have endemically reduced locomotor ability; a conservative estimate is that 30% of birds in a flock are likely to have poor mobility (Knowles et al, 2008). Leg weakness has a direct impact on production due to lower bird quality, which ma ...

I. INTRODUCTIONA hen’s physiological patterns including FI and BW trajectory are established by early lay (Muir et al. 2022). Therefore, management tools such as lighting and feeding programs during rearing may offer opportunities to regulate bird size and establish feeding habits by the end of rearing. This may also influence persistency of lay, egg quality and hen health during an extended ...

I. INTRODUCTIONWith ongoing genetic selection for improved persistency of lay and feed efficiency (FE) in laying hens, the egg industry is pursuing the opportunity to extend layer hen lifespan until they are 100 weeks of age (WOA), with an aim for each hen to produce up to 500 eggs. This presents some challenges for the hen as during this longer laying cycle she will be producing more than 31 kg o ...

I. IntroductionPullet body weight (BW) has significant impact on hen sexual maturity, egg productivity and flock uniformity (Lacin et al. 2009). Australian layer flocks are frequently 100-300 grams heavier than breed standard weight (BSW) (Parkinson et al. 2015). These birds typically lay larger eggs than LW hens and higher BW is symptomatic of bird obesity which can result in the production of ex ...

I. INTRODUCTION Optimum BW is an important consideration in achieving early maturity, high productivity and uniformity in laying hens (Lacin et al., 2009). Parkinson et al. (2015) noted that it was common for Australian flocks to have an average body weight (BW) 100-300 grams above the breed standard weight (BSW). This higher BW is indicative of bird obesity and is associated with the production o ...