Identification of acoustic parameters for broiler welfare estimate

Abstract

ABSTRACT:Estimates of broiler welfare have subjective character. Nowadays, researchers seek non-invasive features or indicators that may describe this condition in animal production. The aim of this study was to identify acoustic parameters to estimate broiler welfare using the following five vocalization acoustic parameters: energy, spectral centroid, bandwidth, first formant, and second formant. The database that generated the model was obtained from a field experiment with 432 broilers, which half were Cobb ® and half, Ross ® breed, from day 21 to 42, containing bird vocalizations under either welfare or stress conditions. The results of the experiment generated responses to the tested conditions of gender, genetic strain, and welfare. The proposed model was based on the specific response of mean weights for each situation of stress and well-being. From the results, a model was developed to estimate the welfare condition of broilers from the registered information linked to their vocalization.KEYWORDS: signal analysis, broiler production, algorithm. IDENTIFICAÇÃO DE PARÂMETROS ACÚSTICOS PARA ESTIMATIVA DE BEM-ESTAR DE FRANGOS DE CORTE RESUMO:A estimativa do bem-estar de frangos de corte tem caráter subjetivo, e, hoje, pesquisadores buscam características ou indicadores não invasivos que possam caracterizar esta condição na produção animal. O objetivo deste trabalho foi identificar parâmetros acústicos que possam ser utilizados na estimativa de bem-estar de frango de corte. Cinco parâmetros acústicos da vocalização foram testados: energia, centroide espectral, largura de banda, primeira formante e segunda formante. A base de dados utilizada proveio dos resultados de um experimento de campo, em que foram utilizadas 432 aves, metade da linhagem Cobb ® e a outra da linhagem Ross ® , do 21º ao 42º dia, contendo vocalizações em estado de bem-estar e sem este. Os resultados do experimento geraram respostas para as condições testadas de sexo, linhagem genética e condição de bem-estar. Os pesos médios específicos das respostas, em cada situação de estresse e bem-estar, foram utilizados para propor uma estimativa da situação de bem-estar. A condição de bem-estar dos frangos de corte pôde ser identificada em função de sua vocalização, pela energia do sinal acústico e das formantes 1 e 2, e em função da origem genética das aves. PALAVRAS-CHAVE:análise de sinais, produção de frangos de corte, algoritmo.

Spectral entropy of early-life distress calls as an iceberg indicator of chicken welfare

“…Distress calling appears not to be triggered directly by acute, startling stimuli (loud noise or electric shock [9]; air puff [10]), but rather discomfort or risky contexts: heat stress [11,12], cold stress [13], maternal signalling of threat [14], high density or food/water restriction (manipulated simultaneously [15]) or social isolation [2,9]. More generally, as young chicks are moved from the hatchery to the unfamiliar rearing environment, latency to settle and find resources and comfort is of critical welfare consideration [16], and distress calling is triggered by environmental unfamiliarity [9,13].…”

Poultry welfare monitoring: group-level technologies

“…By putting individual chicks into a climate-controlled chamber and altering the temperature, Moura et al (2008) showed that both the amplitude and the frequency of these calls increased when the temperature dropped. In farm conditions, heat stress leads to distinctive calls by both broilers (Pereira et al, 2014) and layers (Lee et al, 2015). Du et al (2018) monitored the number of vocalisations/bird both during the day and at night and argued that anomalies in this number of calls given by each bird, particularly at night, could be used for welfare assessment.…”

Technology and Poultry Welfare

“…They showed that when temperature decreased, the amplitude and frequency of the vocalizations increased as birds grouped together to reduce heat loss, while during thermal comfort the amplitude and frequency of vocalizations stabilized. Pereira et al [39] identified thermal stress conditions based on broiler vocalizations and verified the existence of different vocalization patterns in heat stressed birds. In this case, the study was based on four vocalization acoustic parameters: energy, bandwidth, and first and second formant (using Praat ® and Matlab ® software).…”