Prediction of meat quality traits in the abattoir using portable near-infrared spectrometers:heritability of predicted traits and genetic correlations with laboratory-measured traits

Background:The possibility of assessing meat quality traits over the meat chain is strongly limited,especially in the context of selective breeding which requires a large number of phenotypes.The main objective of this study was to investigate the suitability of portable infrared spectrometers for phenotyping beef cattle aiming to genetically improving the quality of their meat.Meat quality traits(pH,color,water holding capacity,tenderness)were appraised on rib eye muscle samples of 1,327 Piemontese young bulls using traditional(i.e.,reference/gold standard)laboratory analyses;the same traits were also predicted from spectra acquired at the abattoir on the intact muscle surface of the same animals 1 d after slaughtering.Genetic parameters were estimated for both laboratory measures of meat quality traits and their spectra-based predictions.Results:The prediction performances of the calibration equations,assessed through external validation,were satisfactory for color traits(R^(2) from 0.52 to 0.80),low for pH and purge losses(R^(2) around 0.30),and very poor for cooking losses and tenderness(R^(2) below 0.20).Except for lightness and purge losses,the heritability estimates of most of the predicted traits were lower than those of the measured traits while the genetic correlations between measured and predicted traits were high(average value 0.81).Conclusions:Results showed that NIRS predictions of color traits,pH,and purge losses could be used as indicator traits for the indirect genetic selection of the reference quality phenotypes.Results for cooking losses were less effective,while the NIR predictions of tenderness were affected by a relatively high uncertainty of estimate.Overall,genetic selection of some meat quality traits,whose direct phenotyping is difficult,can benefit of the application of infrared spectrometers technology.

Contralateral delayed endolymphatic hydrops: Clinical features and long term outcome

Background:Contralateral delayed endolymphatic hydrops(CDEH)is a clinical entity characterized by fluctuating low frequency hearing loss and/or vertigo,mimicking Meniere’s disease(MD),that manifests after the appearance of severe non-hydropic hearing loss(NHHL)at the other ear.Objectives:to describe the clinical features and the course of 57 patients affected by CDEH.Method:this is a retrospective study;57 patients affected by CDEH,out of 1065 patients seen in the same period and affected by MD,were subjected to otoscopy,PTA threshold evaluation,impedance testing,ABR,research of positioning nystagmus,vestibular function evaluated by means of bithermal caloric test under video-oculographic,and MRI with gadolinium.Results:the CDEH was definite in 24 cases(42%),probable in 2(4%)and possible in 31(54%).The mean PTA threshold at the hydropic ear was 41 dB.At the last follow-up,40 patients(70%)did not report vertigo or fluctuating hearing loss.Among the 17 patients who still reported symptomatology,11(64%)were affected by fluctuating hearing loss alone,4(23%)reported a subjective worsening of hearing loss and 2(12%)an acute vertigo crisis.Conclusions:contralateral delayed endolymphatic hydrops is a relatively rare form of Meniere disease that manifests more frequently as a definite form or with fluctuating low-frequency hearing loss.The prognosis at a long term follow-up is relatively good in terms of vertigo resolution.Contralateral delayed endolymphatic hydrops rarely determines a severe hearing loss in the better ear.