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Background: Caseous lymphadenitis (CLA) is a chronic disease caused by the bacterium Corynebacterium pseudotuberculosis that affects small ruminants worldwide. Aim: The objective of this case report is to describe an outbreak of CLA that occurred at the California State Polytechnic University, Pomona, in the summer of 2019 and the management strategies employed therein to contain the spread. Methods: After careful physical screening, blood serum samples from the entire herd (n = 218 sheep, n = 32 goats) were tested using the synergistic hemolysis inhibition test to reveal antibodies present. Results: Animals with titer counts above 1:64 and/or containing CLA lesions were isolated and culled (n = 33 sheep, n = 4 goats) within 2 weeks of testing. Female sheep (n = 160) had higher titer counts and were culled at a much higher rate than male sheep (n = 58) (20% vs. 1.72%), whereas male goats (n = 9) more often had high titer counts and were culled as opposed to female goats (n = 23) (33.33% vs. 4.35%). Conclusion: Vaccines were administered to the remainder of the herd following culling. Additional management strategies were employed, the outcome of which was a zero recurrence through August 2021. [ABSTRACT FROM AUTHOR]

Central 02 chemoreception was assessed in tadpoles of varying developmental stages and frogs (Rana catesbeiana). Brainstems were removed en bloc from anesthetized animals and neuroventilatory gill and lung bursts were recorded from the facial and hypoglossal nerves at their exit points from the brainstem. Recordings were made while each brainstem was superfused with normoxic or hypoxic artificial cerebrospinal fluid (aCSF). Superfusion of the brainstem with hypoxic aCSF elicited an increase in fictive lung ventilation across all stages of development. Early- and late-stage tadpoles showed burst frequency increases in the 1st hour of hypoxia, while frequency decreased with prolonged hypoxia. Middle-stage tadpoles exhibited increased burst frequency in the 3rd hour of hypoxia. Gill burst frequency remained constant throughout 3h of hypoxic exposure in all developmental stages. Therefore, like the central hypercapnic response, the central hypoxic response manifests as an increase in lung ventilation in tadpoles. Some tadpole brainstems became apneic (total loss of gill and lung bursts); however, this event was rare. Superfusion of frog brainstems with hypoxic aCSF elicited an increase in lung burst frequency during the 1st hour of hypoxia and a decrease during continued hypoxia. Apnea was common among frog brainstems exposed to prolonged hypoxia. Most brainstems, tadpole and adult, regained rhythm after the 3-hour hypoxic exposure when normoxic superfusion was re-instated. This study characterized the hypoxic response of R catesbeiana as an increase in neuroventilatory lung bursts with a decrease during prolonged exposure common among adults. Frogs and tadpoles were also shown to be highly hypoxia tolerant. [ABSTRACT FROM AUTHOR]