Septicemia a possibility.
The blue gums (cyanosis) makes me wonder about the possibility of a congenital cardiovascular anomaly... ventricular septal defect and translocation of the left coronary artery to the pulmonic trunk are common occurrences, but others anomalies like Tetralogy of Fallot and similar developmental screw-ups do occur from time to time.
I had such thought too. That's a calf from another nearby beef farm. It's the first calving season for them. No experience with cattle before. They have bought 15 purebred Aubrac heifers and purebred bull. Two heifers had uterine prolapse, one died in minutes. Had one weak calf at birth, which died soon, one calf died after one week and now this calf. I've a feeling that that's not the last loss for them... Not all heifers have calved yet.
Sounds like there is more to this than at first look since this is the third problem. The prolapses can be a combination of things or just bad luck. The problems with the calves makes me tend to think there might also be a nutritional problem somewhere. Plus what about the bloodline? Maybe a deformity? @WalnutCrest knows more about Aubracs. I have bred several to Aubrac semen for calves next year, and have enough to breed another 15 so sure hope this isn't some hidden problem I need to watch out for.
Aubracs are very hardy, nice breed. Normally no such problems.
We think that there is somekind of problem too. Either nutritional, or maybe genetical, because all cattle were bought from abroad and that's not the first time we heard bad experiences with cattle bought this way. Talked with that farmer before. Cattle grazed during summer, brought home in October. Fed hay, minerals and abit of meal. Said to the owner that he better consult with the vet, maybe blood test needed for cows. It's truly very stressful start of farming for those people.