As an attempt to find an inexpensive and simple laboratory method for artificial insemination (AI) bull semen quality assessment, the osmotic resistance of spermatozoa was measured using the hypoosmotic swelling (HOS) test, developed by Jeyendran et al. (1984) (labelled HOS-1), and its modifications (HOS-2, HOS-3), with decreased osmotic pressure aimed at challenging sperm survival ability. The...

ANGUSJournal n September 2011 Breeder question No. 1 Which is more important when doing a bull BSE, measuring a bull’s scrotal circumference or evaluating the semen that he produces? Response: Scrotal measurements and semen characteristics are both important! This is proven by the change made in the Society for Theriogenology’s breeding soundness exam in 1992. The exam was changed from a numeri...

The Northern kelp crab (Pugettia producta) and the graceful kelp crab (Pugettia gracilis) are common primary consumers in bull kelp beds near the San Juan Islands (Salish Sea, NE Pacific). In this system, urchins (often considered the most voracious herbivores exerting top-down control on kelp beds) tend to remain sedentary because of the high availability of detrital macroalgae, but the extent...