Recent success propagating captive beluga has resulted from combined efforts by North American zoos and aquariums to manage disparate collections as a single population. This success has provided a tremendous opportunity to increase our understanding of beluga reproductive biology. Blood samples were collected on a weekly to biweekly basis from 23 female and 12 male beluga, ranging in age from 2-15 years, for analysis of serum progesterone (P) and testosterone (T), respectively. Peri-parturient observational data, including food intake, duration and signs of labor, and nursing patterns were collected from 15 days prepartum to 30 days postpartum during 21 births. Total body lengths and weights were collected from 10 captive-born beluga. For female beluga, the mean (7SD) age, body length, and weight at first conceptions were 9.172.8 years, 318.079.1 cm, and 519784 kg. Thirty-five luteal phases and 13 conceptions were detected from January-June, and 70% of luteal phases and 80% conceptions occurred from March-May. The mean luteal phase and total estrous cycle lengths were 30.076.5 days and 48.074.6 days, respectively. For male beluga, the mean age that males sired their first calf was 13.372.6 years. Compared to younger males (o8 years of age, 0.95 ng/ml), levels of T secretion in older males (48 years of age, 5.0 ng/ml) were elevated significantly only during the interval from January-April. Highest T concentrations (6.274.9 ng/ml) were recorded from January-March, whereas nadir concentrations (1.171.0 ng/ml) were detected from August-September. The mean gestation length was 475.0720.4 days (n ¼ 9). For parturition, the mean time from the first appearance of fluke or rostrum to delivery, delivery to placental passage, and delivery to nursing were 4.472.9 hr, 7.671.8 hr, and 43745 hr, respectively. All cows had decreased food intake on the day of delivery, with 44% having zero intake. Peak 24-hr nursing activity occurred 3.972.7 days post-partum. Growth (i.e., body weight and length) as a function of age were well described by the Gompertz model (r 2 ¼ 0.91, 0.93). Based on the model, growth in body weight and length were significantly greater in males compared to females. Predicted birth weight (88.9 kg) was similar for both sexes, however, and male calves were predicted to be shorter (154.3 cm) than female calves (160.7 cm). The results provide the first descriptions of captive beluga reproductive physiology, including endocrinology, peri-parturient behavior, growth, and reproductive maturity. This knowledge is important for helping to maintain genetically diverse, self-sustaining populations of captive beluga whales.

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Although immune attack against central nervous system (CNS) myelin is a central feature of multiple sclerosis (MS), its root cause is unresolved. In this report, we provide direct evidence that subtle biochemical modifications to brain myelin elicit pathological immune responses with radiological and histological properties similar to MS lesions. A subtle myelinopathy induced by abbreviated cuprizone treatment, coupled with subsequent immune stimulation, resulted in lesions of inflammatory demyelination. The degree of myelin injury dictated the resulting immune response; biochemical damage that was too limited or too extensive failed to trigger overt pathology. An inhibitor of peptidyl arginine deiminases (PADs), enzymes that alter myelin structure and correlate with MS lesion severity, mitigated pathology even when administered only during the myelin-altering phase. Moreover, cultured splenocytes were reactive against donor myelin isolates, a response that was substantially muted when splenocytes were exposed to myelin from donors treated with PAD inhibitors. By showing that a primary biochemical myelinopathy can trigger secondary pathological inflammation, "cuprizone autoimmune encephalitis" potentially reconciles conflicting theories about MS pathogenesis and provides a strong rationale for investigating myelin as a primary target for early, preventative therapy.

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ABSTRACT:Domoic acid is a glutaminergic neurotoxin produced by marine algae such as Pseudonitzschia australis. California sea lions (Zalophus californianus) ingest the toxin when foraging on planktivorous fish. Adult females comprise 60% of stranded animals admitted for rehabilitation due to acute domoic acid toxicosis and commonly suffer from reproductive failure, including abortions and premature live births. Domoic acid has been shown to cross the placenta exposing the fetus to the toxin. To determine whether domoic acid was playing a role in reproductive failure in sea lion rookeries, 67 aborted and live-born premature pups were sampled on San Miguel Island in 2005 and 2006 to investigate the causes for reproductive failure. Analyses included domoic acid, contaminant and infectious disease testing, and histologic examination. Pseudo-nitzschia spp. were present both in the environment and in sea lion feces, and domoic acid was detected in the sea lion feces and in 17% of pup samples tested. Histopathologic findings included systemic and localized inflammation and bacterial infections of amniotic origin, placental abruption, and brain edema. The primary lesion in five animals with measurable domoic acid concentrations was brain edema, a common finding and, in some cases, the only lesion observed in aborted premature pups born to domoic acid-intoxicated females in rehabilitation. Blubber organochlorine concentrations were lower than those measured previously in premature sea lion pups collected in the 1970s. While the etiology of abortion and premature parturition was varied in this study, these results suggest that domoic acid contributes to reproductive failure on California sea lion rookeries.

Abstract:With the rapid increase in new fNIRS users employing commercial software, there is a concern that many studies are biased by suboptimal processing methods. The purpose of this study is to provide a visual reference showing the effects of different processing methods, to help inform researchers in setting up and evaluating a processing pipeline. We show the significant impact of pre-and post-processing choices and stress again how important it is to combine data from both hemoglobin species in order to make accurate inferences about the activation site.

Concussion, or mild traumatic brain injury (mTBI), accounts for ∼80% of all TBIs across North America. The majority of mTBI patients recover within days to weeks; however, 14–36% of the time, acute mTBI symptoms persist for months or even years and develop into persistent post-concussion symptoms (PPCS). There is a need to find biomarkers in patients with PPCS, to improve prognostic ability and to provide insight into the pathophysiology underlying chronic symptoms. Recent research has pointed toward impaired network integrity and cortical communication as a biomarker. In this study we investigated functional near-infrared spectroscopy (fNIRS) as a technique to assess cortical communication deficits in adults with PPCS. Specifically, we aimed to identify cortical communication patterns in prefrontal and motor areas during rest and task, in adult patients with persistent symptoms. We found that (1) the PPCS group showed reduced connectivity compared with healthy controls, (2) increased symptom severity correlated with reduced coherence, and (3) connectivity differences were best distinguishable during task and in particular during the working memory task (n-back task) in the right and left dorsolateral prefrontal cortex (DLPFC). These data show that reduced brain communication may be associated with the pathophysiology of mTBI and that fNIRS, with a relatively simple acquisition paradigm, may provide a useful biomarker of this injury.

Concentrations of plasma adrenocorticotropic hormone (ACTH), cortisol, and aldosterone were investigated in three adult beluga whales (Delphinapterus leucas), held in a large outdoor public aquarium exhibit. The purpose of this study was to evaluate resting concentrations of these hormones and associated diurnal variations with routine interactions and medical procedures. Resting blood samples were collected voluntarily from the ventral fluke veins at predetermined times of the day to evaluate diurnal changes in analyte concentrations. In addition, hematology and serum chemistry analyses were performed to monitor health status and evaluate changes related to physical exam procedures. Analogous sampling was conducted during out‐of‐water physical examinations and before and after wading‐contact sessions (WCS). Baseline stress hormone concentrations (± SD) were as follows: plasma ACTH (8.41 ± 5.8 pg/mL), serum cortisol (1.80 ± 0.71 g/dL), and serum aldosterone (11.42 ± 5.5 pg/mL). Plasma ACTH and cortisol concentrations were consistently higher in early morning than evening, while aldosterone was higher in the evening. All stress‐related hormones were significantly elevated during physical examination. Plasma ACTH concentrations were most increased, 5–10‐fold, during physical examination, whereas cortisol and aldosterone showed 2–4‐fold elevations. Stress response analytes measured during the WCS did not differ significantly from baseline concentrations.