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In a studbook, MULT is used in a parent ID field when the actual parent is unknown but the parent is known to be one of a set of possible parents. Probabilities of being the actual parent are assigned to each possible parent in the MULT group, and that information is used in the calculation of mean kinships (MKs). Parental probabilities are typically assigned based on the species biology and/or what was known about how the animals were being managed at the time of conception. If there is no additional information, the default is to assign each possible parent the same probability. What has not been considered to date is the impact of different MKs among the group of possible parents. Methods are developed which allow a combination of parental probabilities and MKs into parental weights. These weights replace parental probabilities in the analysis. One important conclusion is that even when the MKs of possible parents are quite different, the difference between the parental weights and probabilities is typically less than 30%. This highlights the importance of correct estimation of parental probabilities, whenever possible, instead of reliance on a default.

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Animals with only partially known ancestry present a problem for population managers because it can be difficult to determine their relative genetic value to the population. So long as their ancestry is not completely unknown, population management software such as PMx can calculate a mean kinship for these animals, but that mean kinship is calculated such that there is no decrease in relative genetic value or "penalty" for only partially known ancestry. However, there is a longer-term genetic cost to having animals with only partially known ancestry in the population, and thus it is appropriate to "penalize" animals with partially known ancestry to some extent. The challenge is determining the correct "penalty" which will serve to decrease the percent unknown ancestry in subsequent generations while not causing excessive selection against the known ancestry of the animal. A new parameter of relative genetic value is developed which takes into account both an animal's mean kinship as well as its percent known ancestry. The method used in PMx to calculate the mean kinships also in general overestimates the inbreeding coefficients of offspring of animals with partially known ancestry when the known parents share a common ancestor, but can underestimate inbreeding if common ancestors exist within the unknown portion of the pedigree. This may result in population managers selecting less suitable pairs for breeding in an attempt to avoid an apparent higher level of inbreeding. A parameter is developed that adjusts the inbreeding coefficient to more accurately reflect the likely inbreeding coefficient of potential offspring. Zoo Biol. 35:319-325, 2016. © 2016 Wiley Periodicals, Inc.

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Franks et al. (2016) consider that the degree of error in estimated ages used to define survivorship patterns of northern and southern resident killer whale ( Orcinus orca ) populations is of insignificant impact to estimates of the species' postreproductive lifespan (PRLS). We provide evidence that survival probabilities for killer whales using a dataset comprising estimated age animals differ significantly from that determined using data collected from known-age animals in the Pacific Northwest over the past 40 years. Consequently, our findings indicate that the degree of error in age estimates and ensuing survivorship patterns do not support the notion by Franks et al. (2016) of a prolonged PRLS in the female killer whale that is comparable to the PRLS observed in humans.

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Data collected on life-history parameters of known-age animals from the northern (NR) and southern resident (SR) killer whales (Orcinus orca) of the eastern North Pacific were compared with life-history traits of killer whales located at SeaWorld (SEA) facilities. For captive-born SEA animals, mean age and body length at 1st estrus was 7.5 years and 483.7cm, respectively. Estimated mean age at 1st conception was different (P < 0.001) for the combined data from both northern and southern resident (NSR) free-ranging populations (12.1 years) compared to SEA (9.8 years), as was the estimated mean age at 1st observed calf (SEA: 11.1 years, NSR: 14.2 years, P < 0.001). Average calf survival rate to 2 years of age for SEA animals (0.966) was significantly greater (P = 0.04) than that for SR (0.799). Annual survival rate (ASR) for SEA increased over approximately 15-year increments with rates in the most recent period (2000-2015 ASR: 0.976) improved (P < 0.05) over the first 2 periods of captivity (1965-1985: 0.906; 1985-2000: 0.941). The SR (0.966) and NR ASR (0.977) were higher (P ≤ 0.05) than that of SEA until 2000, after which there were no inter-population differences. Based on ASR, median and average life expectancy were 28.8 and 41.6 years (SEA: 2000-2015), 20.1 and 29.0 years (SR), and 29.3 and 42.3 years (NR), respectively. The ASR for animals born at SEA (0.979) was higher (P = 0.02) than that of wild-caught SEA animals (0.944) with a median and average life expectancy of 33.1 and 47.7 years, respectively. These data present evidence for similar life-history parameters of free-ranging and captive killer whale populations and the reproductive potential and survivorship patterns established herein have application for use in future research concerning the overall health of both populations.

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In 2010, unhealthy diets were estimated to be the leading risk for death and disability in Canada and globally. Although important, policies aimed at improving individual's skills in selecting and eating healthy foods has had a limited effect. Policies that create healthy eating environments are strongly recommended but have not yet been effectively and/or broadly implemented in Canada. Widespread adoption of healthy food procurement policies are strongly recommended in this policy statement from the Hypertension Advisory Committee with support from 15 major national health organizations. The policy statement calls on governments to take a leadership role, but also outlines key roles for the commercial and noncommercial sectors including health and scientific organizations and the Canadian public. The policy statement is based on a systematic review of healthy food procurement interventions that found them to be almost uniformly effective at improving sales and purchases of healthy foods. Successful food procurement policies are nearly always accompanied by supporting education programs and some by pricing policies. Ensuring access and availability to affordable healthy foods and beverages in public and private sector settings could play a substantive role in the prevention of noncommunicable diseases and health risks such as obesity, hypertension, and ultimately improve cardiovascular health.

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Demographic changes and improvements in health care are projected to result in dramatic increases in the prevalence of dementia. Alzheimer's disease is widely considered to be the primary cause of dementia - a disease for which there is currently no cure nor effective treatment, and for which it is thought that little can be done to mitigate risk. However, an increasing understanding of the role and extent of vascular contributions to the development of dementia, and appreciation of the interactions between stroke and Alzheimer's disease, suggest that targeting vascular risk factors may be very beneficial in reducing the impact of dementia. We also describe how active stimulation of the brain throughout the life course builds cognitive reserve that can offset or compensate for cognitive decline in later life. Finally, we discuss the implications of these emerging approaches for dementia prevention and advocate for the urgent implementation of more extensive public health strategies to improve vascular health.

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Hypertension is the leading risk for premature death in the world. High dietary sodium is an important contributor to increased blood pressure and is strongly associated with other important diseases (e.g., gastric cancer, calcium containing kidney stones, osteoporosis, asthma and obesity). The average dietary sodium intake in Canada is approximately 3400 mg/day. It is estimated that 30% of hypertension, more than 10% of cardiovascular events and 1.4 billion dollars/year in health care expenses are caused by this high level of intake in Canada. Since 2006, Canada has had a focused and evolving effort to reduce dietary sodium based on actions from Non Governmental Organizations (NGO), and Federal and Provincial/Territorial Government actions. NGOs initiated Canadian sodium reduction programs by developing a policy statement outlining the health issue and calling for governmental, NGO and industry action, developing and disseminating an extensive health care professional education program including resources for patient education, developing a public awareness campaign through extensive media releases and publications in the lay press. The Federal Government responded by striking a Intersectoral Sodium Work Group to develop recommendations on how to implement Canada's dietary reference intake values for dietary sodium and by developing timelines and targets for foods to be reduced in sodium, assessing key research gaps with funding for targeted dietary sodium based research, developing plans for public education and for conducting evaluation of the program to reduce dietary sodium. While food regulation is a Federal Government responsibility Provincial and Territorial governments indicated reducing dietary sodium needed to be a priority. Federal and Provincial Ministers of Health have endorsed a target to reduce the average consumption of sodium to 2300 mg/day by 2016 and the Deputy Ministers of Health have tasked a joint committee to review the recommendations of the Sodium Work Group and report back to them.

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The number of population founders and the size of the population are two important variables in determining how much gene diversity can be retained in a population. A model is developed to determine the most cost-effective balance of those two variables, based on comparing the marginal costs of increasing the number of founders vs. increasing the population size. Marginal costs, in this case, are the costs of increasing the number of founders or the population size by one animal. For a goal of retaining 90% gene diversity for 10-15 generations (approximately 100 years), the current recommendation of 20 effective founders is very close to the least-cost solution when the ratio of the marginal costs is equal to one. However, when the ratio is greater or less than one that number can change considerably.

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