Warner-Bratzler shear force values and ranges of steaks from cattle of known sires

Carcass data and Warner-Bratzler shear force (WBSF) data on strip loin steaks were collected from nearly 8,500 cattle in contemporary groups of progeny from the more popular sires in 14 different beef cattle breeds in the Carcass Merit Traits project funded by Beef Checkoff dollars, the breed associations, and MMI Genomics. In addition, trained sensory panel evaluations were conducted on over 2,500 strip loin steaks from contemporary groups of progeny from five sires included in the DNA marker validation component of the project. The correlation between WBSF and tenderness scored by the trained sensory panel was -0.82, indicating that as WBSF increased, tenderness scored by the sensory panel decreased. Our results showed that a WBSF value of ≥ 11.0 lb generally results in a sensory score of slightly tough or tougher. In this study, 22.8% of the cattle had WBSF values ≥ 11.0 lb and 26.3% had sensory scores of slightly tough or tougher. The phenotypic range of WBSF means for sires within breeds ranged from 1.9 to 6.6 lb. The phenotypic range of WBSF means across breeds was 8.9 lb, whereas the range among sires across breeds was a dramatic 14.4 lb. The phenotypic range for flavor intensity scores among sires within and across breeds was much smaller than for tenderness, with juiciness scores being intermediate. The 40 widely used sires that produced progeny with steaks that were unacceptable in tenderness in this study might be expected to be sires of several thousand bulls used in commercial herds. This demonstrates that seedstock producers should aggressively utilize sires that have genetics for tender meat

Para-infectious brain injury in COVID-19 persists at follow-up despite attenuated cytokine and autoantibody responses

To understand neurological complications of COVID-19 better both acutely and for recovery, we measured markers of brain injury, inflammatory mediators, and autoantibodies in 203 hospitalised participants; 111 with acute sera (1–11 days post-admission) and 92 convalescent sera (56 with COVID-19-associated neurological diagnoses). Here we show that compared to 60 uninfected controls, tTau, GFAP, NfL, and UCH-L1 are increased with COVID-19 infection at acute timepoints and NfL and GFAP are significantly higher in participants with neurological complications. Inflammatory mediators (IL-6, IL-12p40, HGF, M-CSF, CCL2, and IL-1RA) are associated with both altered consciousness and markers of brain injury. Autoantibodies are more common in COVID-19 than controls and some (including against MYL7, UCH-L1, and GRIN3B) are more frequent with altered consciousness. Additionally, convalescent participants with neurological complications show elevated GFAP and NfL, unrelated to attenuated systemic inflammatory mediators and to autoantibody responses. Overall, neurological complications of COVID-19 are associated with evidence of neuroglial injury in both acute and late disease and these correlate with dysregulated innate and adaptive immune responses acutely

Heritability and correlation estimates of Warner-Bratzler shear force and marbling score from Angus-, Charolais-, Hereford-, and Simmental-sired cattle

The objective of this study was to estimate heritabilities and genetic correlations for Warner- Bratzler shear force and marbling score of longissimus steaks from Angus-, Charolais-, Hereford-, and Simmental-sired cattle in the National Cattlemen’s Beef Association (NCBA) coordinated Carcass Merit Traits Project funded with Beef Checkoff dollars. There were 700 Angus-sired steers, 691 Charolais-sired steers and heifers, 938 Hereford-sired steers, and 1,167 Simmental-sired steers and heifers in the study. Restricted maximum likelihood estimates of the genetic parameters were determined using a sire model with a sire/maternal grandsire relationship matrix. The heritabilities for Warner-Bratzler shear force and marbling score, respectively, were 0.35 and 0.36 for Angus, 0.43 and 0.26 for Charolais, 0.12 and 0.59 for Hereford, and 0.13 and 0.42 for Simmental. The genetic and phenotypic correlations between Warner-Bratzler shear force and marbling score, respectively, were -0.19 and -0.18 for Angus; -0.36 and -0.19 for Charolais; - 0.47 and -0.23 for Hereford; and +0.64 and - 0.11 for Simmental. The high positive genetic correlation between Warner-Bratlzer shear force and marbling score for Simmental sires indicates that as marbling increased Warner- Bratzler shear force increased (decreased tenderness). These results suggest that selection for increased marbling in the Simmental breed would actually have a detrimental effect on tenderness. Selection for Warner-Bratzler hear force in Angus and Charolais could result in improved in tenderness, but little progress would be expected in Hereford sired cattle. In general, selection for marbling score in these breeds would improve tenderness only minimally