A Large‐Scale SNP‐Based Genomic Admixture Analysis of the Captive Rhesus Macaque Colony at the California National Primate Research Center

Some breeding facilities in the United States have crossbred Chinese and Indian rhesus macaque (Macaca mulatta) founders either purposefully or inadvertently. Genetic variation that reflects geographic origins among research subjects has the potential to influence experimental outcomes. The use of animals from different geographic regions, their hybrids, and animals of varying degrees of kinship in an experiment can obscure treatment effects under study because high interanimal genetic variance can increase phenotypic variance among the research subjects. The intent of this study, based on a broad genomic analysis of 2,808 single nucleotide polymorphisms (SNPs), is to ensure that only animals estimated to be of pure Indian or Chinese ancestry, based on both demographic and genetic information, are used as sources of infants for derivation and expansion of the California National Primate Research Center's (CNPRC) super‐Specific Pathogen Free (SSPF) rhesus macaque colony. Studies of short tandem repeats (STRs) in Indian and Chinese rhesus macaques have reported that heterozygosity of STRs is higher in Chinese rhesus macaques than in Indian rhesus macaques. The present study shows that heterozygosity of SNPs is actually higher in Indian than in Chinese rhesus macaques and that the Chinese SSPF rhesus macaque colony is far less differentiated from their founders compared to the Indian‐origin animals. The results also reveal no evidence of recent gene flow from long‐tailed and pig‐tailed macaques into the source populations of the SSPF rhesus macaques. This study indicates that many of the long‐tailed macaques held in the CNPRC are closely related individuals. Most polymorphisms shared among the captive rhesus, long‐tailed, and pig‐tailed macaques likely predate the divergence among these groups. Am. J. Primatol. 74:747‐757, 2012. © 2012 Wiley Periodicals, Inc.     

Changes in haematological parameters in relation to prey switching in a wild population of harbour seals

1. Previous studies have found marked inter-annual variation in winter food availability, diet composition and body condition in a population of harbour seals ( Phoca vitulina L.) in Northeast Scotland. This study aimed to determine whether there were other physiological consequences of prey switching by comparing haematological parameters in years when the clupeids herring and sprat dominated the diet and in years when seals switched to alternative prey.
2. There were significant differences in leukocyte and erythrocyte parameters in relation to diet composition. In contrast, indices of body condition did not explain the variation in haematological parameters, suggesting that the observed changes did not result from differences in the energetic content of the prey.
3. Leukocyte counts were significantly higher after 'good' clupeid years, although the differences in mean counts were small. Such differences could have resulted either from immuno-suppression, for example because of differences in prey nutrient or contaminant levels, or from differences in the pathogen challenge resulting from geographical variations in water quality.
4. The differences in erythrocyte parameters were more marked, and there was evidence of widespread macrocytic anaemia when seals switched from clupeids to alternative prey. Such differences could result either from acclimation, as a result of prey-specific foraging strategies, or from differences in the nutritional quality of prey.
5. These results indicate that generalist predators such as the harbour seal may exhibit physiological responses to changes in the composition of their diet. These data highlight the need to consider the long-term physiological effects of variations in food availability on the population dynamics of generalist marine top predators. In particular, it is hypothesized that fish-induced anaemia may be responsible for declines in certain pinniped populations.