Correlation of Anti-Müllerian hormone serum concentration measured in proestrus and estrus with the litter size as a fertility marker in bitches.

The use of the anti-Müllerian hormone (AMH) serum concentration as a fertility marker has been shown in cows, sheep and mares and has been indicated in one study in female dogs. The aim of this study was to investigate the connection between the AMH serum concentration, taken at two defined time points during the bitch`s heat, and the litter size to investigate whether AMH can be used as a practical measurement for the individual breeding bitch to predict litter size. The study was carried out on 27 healthy female dogs presented for pre-breeding examination, considering all previously known influencing factors on AMH in the bitch such as age, body weight and estrous cycle phase at the time the sample was taken.

Identification of a Resistance Exercise-Specific Signaling Pathway that Drives Skeletal Muscle Growth.

A human model of unilateral endurance versus resistance exercise, in conjunction with deep phosphoproteomic analyses, was used to identify exercise mode-specific phosphorylation events. Among the outcomes, a resistance exercise-specific cluster of events was identified, and a multitude of bioinformatic- and literature-based predictions suggested that this was mediated by prolonged activation of a pathway involving MKK3b/6, p38, MK2, and mTORC1. Follow-up studies in humans and mice provide consistent support for the predictions and also revealed that resistance exercise-induced signaling through MKK3b and the induction of protein synthesis are highly correlated events (R = 0.

Satellite cell-derived TRIM28 is pivotal for mechanical load- and injury-induced myogenesis.

Satellite cells are skeletal muscle stem cells that contribute to postnatal muscle growth, and they endow skeletal muscle with the ability to regenerate after a severe injury. Here we discover that this myogenic potential of satellite cells requires a protein called tripartite motif-containing 28 (TRIM28). Interestingly, different from the role reported in a previous study based on C2C12 myoblasts, multiple lines of both in vitro and in vivo evidence reveal that the myogenic function of TRIM28 is not dependent on changes in the phosphorylation of its serine 473 residue.

The utility-and limitations-of the rodent synergist ablation model in examining mechanisms of skeletal muscle hypertrophy.

In this issue, Burke et al. discuss the utility of the rodent synergist ablation (SA) model for examining mechanisms associated with skeletal muscle hypertrophy. In this invited perspective, we aim to complement their original perspective by discussing limitations to the model along with alternative mechanical overload models that have strengths and limitations.

A novel imaging method (FIM-ID) reveals that myofibrillogenesis plays a major role in the mechanically induced growth of skeletal muscle.

An increase in mechanical loading, such as that which occurs during resistance exercise, induces radial growth of muscle fibers (i.e. an increase in cross-sectional area).