Photoperiodic responses of broilers. I. Growth, feeding behaviour, breast meat yield, and testicular growth

British Poultry Science
P D LewisR M Gous

Abstract

1. A total of 7960 Cobb and Ross broiler males were reared in two trials to 35 d on various photoperiods between 2 and 21 h or under continuous illumination; a total of 444 birds were randomly selected at 35 d and retained for subsequent determination of breast meat yield and testicular weight at 40 or 54 d of age. 2. In both strains, feed intake and growth were positively correlated with photoperiod during the first 21 d, but afterwards feed intake was not significantly affected by photoperiods longer than 6 h and growth was negatively correlated with photoperiod beyond 12 h. Overall, to 35 d, there were no significant photoperiodic influences on either feed intake or growth for >or=6-h photoperiods, but significant depressions in feed intake and growth for photoperiods shorter than 6 h. Feed conversion efficiency was maximised by 12-h photoperiods, with decreases in efficiency above and below 12 h. Mortality was unaffected by photoperiod <12 h, but increased proportionately with photoperiod >12 h. The incidence of Sudden Death Syndrome (SDS) had an inverse relationship with photoperiod <or=10 h, but was positively correlated with photoperiod >10 h. The European Efficiency Factor was curvilinearly related to photoperiod, with ...Continue Reading

References

Mar 1, 1991·British Poultry Science·H L ClassenF E Robinson
Jul 1, 1989·Poultry Science·H L Classen, C Riddell
Jul 1, 1968·Poultry Science·W D Weaver, P B Siegel
Mar 1, 1984·Poultry Science·J L WilsonJ A Cherry
Mar 2, 1999·Poultry Science·E J ApeldoornH K Parmentier
Dec 1, 1999·British Poultry Science·I RozenboimA Rosenstrauch
Oct 31, 2003·British Poultry Science·P D LewisR M Gous
Oct 16, 2004·British Poultry Science·P D LewisR M Gous

❮ Previous
Next ❯

Citations

Jul 1, 2010·Acta Veterinaria Scandinavica·Victoriya V VolkovaRobert W Wills
Jan 8, 2019·Poultry Science·Mohamed F FarghlyShengqing Yu
Dec 1, 2009·British Poultry Science·P D Lewis, R M Gous
Apr 3, 2020·British Poultry Science·L VargasC Fisher
Mar 4, 2021·Animals : an Open Access Journal From MDPI·Tz-Chuen JuShyi-Kuen Yang

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.