Dissection of ancestral genetic contributions to Creole goat populations.

Goats have played a key role as source of nourishment for humans in their expansion all over the world in long land and sea trips. This has guaranteed a place for this species in the important and rapid episode of livestock expansion triggered by Columbus' arrival in the Americas in the late 1400s. The aims of this study are to provide a comprehensive perspective on genetic diversity in American goat populations and to assess their origins and evolutionary trajectories. This was achieved by combining data from autosomal neutral genetic markers obtained in more than two thousand samples that encompass a wide range of Iberian, African and Creole goat breeds. In general, even though Creole populations differ clearly from each other, they lack a strong geographical pattern of differentiation, such that populations of different admixed ancestry share relatively close locations throughout the large geographical range included in this study. Important Iberian signatures were detected in most Creole populations studied, and many of them, particularly the Cuban Creole, also revealed an important contribution of African breeds. On the other hand, the Brazilian breeds showed a particular genetic structure and were clearly separated from the other Creole populations, with some influence from Cape Verde goats. These results provide a comprehensive characterisation of the present structure of goat genetic diversity, and a dissection of the Iberian and African influences that gave origin to different Creole caprine breeds, disentangling an important part of their evolutionary history. Creole breeds constitute an important reservoir of genetic diversity that justifies the development of appropriate management systems aimed at improving performance without loss of genomic diversity.

Genetic characterization of local Criollo pig breeds from the Americas using microsatellite markers.

Little is known about local Criollo pig genetic resources and relationships among the various populations. In this paper, genetic diversity and relationships among 17 Criollo pig populations from 11 American countries were assessed with 24 microsatellite markers. Heterozygosities, F-statistics, and genetic distances were estimated, and multivariate, genetic structure and admixture analyses were performed. The overall means for genetic variability parameters based on the 24 microsatellite markers were the following: mean number of alleles per locus of 6.25 ± 2.3; effective number of alleles per locus of 3.33 ± 1.56; allelic richness per locus of 4.61 ± 1.37; expected and observed heterozygosity of 0.62 ± 0.04 and 0.57 ± 0.02, respectively; within-population inbreeding coefficient of 0.089; and proportion of genetic variability accounted for by differences among breeds of 0.11 ± 0.01. Genetic differences were not significantly associated with the geographical location to which breeds were assigned or their country of origin. Still, the NeighborNet dendrogram depicted the clustering by geographic origin of several South American breeds (Criollo Boliviano, Criollo of northeastern Argentina wet, and Criollo of northeastern Argentina dry), but some unexpected results were also observed, such as the grouping of breeds from countries as distant as El Salvador, Mexico, Ecuador, and Cuba. The results of genetic structure and admixture analyses indicated that the most likely number of ancestral populations was 11, and most breeds clustered separately when this was the number of predefined populations, with the exception of some closely related breeds that shared the same cluster and others that were admixed. These results indicate that Criollo pigs represent important reservoirs of pig genetic diversity useful for local development as well as for the pig industry.

Origins and genetic diversity of British cattle breeds in Brazil assessed by pedigree analyses.

Pedigree information available for Angus (ANG), Devon (DEV), Hereford (HER), and Shorthorn (SHO) cattle in Brazil was analyzed to appraise the genetic diversity and population structure of these breeds. Pedigree records collected from the beginning of the 20th century until 2010 were used in the analyses. Over time, the number of herdbook registrations declined in HER after a peak in the 1970s, remained low in DEV and SHO, and increased steadily in ANG since the 1990s, such that it the latter is now the leading British cattle breed in Brazil. The average number of offspring registered per sire ranged from about 12 (SHO) to 20 (DEV) and the mean generation interval ranged from about 6.0 (HER and SHO) to 6.4 (ANG) years. In the reference population (calves born in 2009 and 2010, plus those born in 2008 for SHO) the mean equivalent number of generations known ranged from about 7 (SHO) to 9 (HER). In the 4 breeds studied, nearly all animals born over the last few years are inbred, even though the mean level of inbreeding in the reference population is below 4% in all breeds. The rate of inbreeding per generation, computed from the individual increase in inbreeding, ranged from about 0.2 (ANG) to 0.5% (DEV), with a corresponding effective population size of 245 and 92, respectively, which is above the recommended minimum critical threshold. The number of founders/ancestors contributing with 50% of the reference population gene pool was 211/26 for ANG, 41/14 for DEV, 164/25 for HER, and 79/10 for SHO, with effective number of founders/ancestors/founder genomes of 470/68/36, 89/33/16, 289/59/30, and 200/28/18 for ANG, DEV, HER, and SHO, respectively. The genetic contribution of different countries to the gene pool of each breed indicated that, throughout the period studied, DEV genes originated predominantly from the United Kingdom, while for the other breeds there was a changing pattern over time. Until the 1970s Argentina was the major supplier of ANG, while HER and SHO genes were mostly from Uruguay, but since then the United States took the leading role as supplier of ANG, HER, and SHO genes to Brazil. Our results reveal a mild increase in inbreeding in all breeds studied, with effective population size estimates indicating that reasonable levels of genetic diversity have been maintained in all 4 breeds. Continuous monitoring of inbreeding trends and of parameters derived from probability of gene origin should be ensured to warrant the long-term maintenance of genetic diversity.

Mortadella sausage manufactured with Caiman yacare (Caiman crocodilus yacare) meat, pork backfat, and soybean oil.

Mortadellas manufactured using Caiman yacare meat (70%) and pork fat (30%) were reformulated by substituting pork fat with increasing amounts of soybean oil (25%, 50%, and 100%) and evaluated 7, 30, and 60 days post-manufacture. The substitutions resulted in an increase in fat content and in the percentage of polyunsaturated fatty acids (total PUFA; 18:2 n-6 and 18:3 n-3), and a reduction in saturated fatty acids (total SFA; 14:0 and 16:0). These alterations reduced (P<0.01) the indices of atherogenicity and thrombogenicity by 4- to 5-fold in the formulation with 100% soybean oil compared to the original formulation. The levels of TBARS obtained at day 7 were positively correlated (P<0.01) with 18:2 n-6 and 18:3 n-3 (r=0.83 and 0.84, respectively) and negatively correlated with 17:0 and 17:1 (r=-0.91 and -0.89, respectively). All formulations received favourable overall acceptability by the sensory panel.

Drift across the Atlantic: genetic differentiation and population structure in Brazilian and Portuguese native goat breeds.

Brazilian goat breeds are believed to derive mainly from animals brought by Portuguese settlers since the 16th century. We used microsatellite markers in a sample of 436 animals to study genetic variability and differentiation of the six Portuguese (PT) and six Brazilian (BR) goat breeds currently recognized in the two countries. These breeds were also compared with an outgroup represented by a sample of Alpine (ALP) goats. The effective number of alleles and allelic richness were slightly higher in PT than in BR breeds. The global F(ST) was nearly 0.11 when PT and BR breeds were considered, with a mean pairwise F(ST) of about 0.03 among PT breeds, 0.07 among BR breeds and 0.15 between PT and BR breeds. The dendrogram illustrating relationships between populations and the correspondence analysis indicate the existence of two very distinct clusters, corresponding to the countries of origin of the breeds studied, which are nearly equidistant from the Alpine outgroup. The analysis with structure confirmed the separation between PT and BR breeds but suggests that some BR breeds, especially Graúna and Canindé, may share a common ancestry with PT breeds. The divergence observed between PT and BR breeds may result from founder effects and genetic drift but could also reflect the introduction in Brazil of goats originating from other regions, e.g., West Africa.

Meat quality and lipid profiles in crossbred lambs finished on clover-rich pastures.

Meat quality traits were compared in Texel x Polwarth and Texel x Corriedale ram lambs, with live weight of 25kg, finished on pastures rich in white clover. The two crossbred groups showed similar results (P>0.05) for pH, moisture, protein, meat color, individual SFA and total SFA. Fat content was higher and cholesterol lower in Texel x Polwarth lambs (P<0.05), which also had higher amounts of MUFA (P<0.05) and lower levels of total PUFA and n-6 PUFA (P<0.01). Differences in meat quality among the two crossbred groups were minor, and possibly not perceptible from the consumer standpoint. However, both groups of lambs produced lean meat with high amounts of PUFA (>16%), possibly due to the ingestion of white clover in the finishing period. Overall, these results indicate that a differentiated product can be obtained in these conditions, with higher nutritional value than conventional lamb meat.

Genotype x environment interactions for fatty acid profiles in Bos indicus and Bos taurus finished on pasture or grain.

A study was conducted to characterize lipid profiles in the M. longissimus thoracis of commercial Brazilian beef and to assess how those profiles are influenced by finishing system, genetic group, and their interaction. Intramuscular fat (IMF) and fatty acid (FA) profiles were determined in 160 bulls of the Bos taurus (n = 75) and Bos indicus (n = 85) genetic groups, finished on pasture (n = 46) or with grain supplementation (n = 114) and slaughtered in a commercial abattoir. Finishing system had a major impact on the deposition of IMF, as well as on the concentration of SFA, PUFA, and their ratio, but genetic groups showed important differences in the ability to convert SFA into cis-9 MUFA and to convert 16:0 into 18:0. When compared with pasture-finished animals, those finished with grain had greater content of IMF and SFA (P < 0.01), similar amounts of MUFA (P > 0.05), and about one-half the amount of PUFA (P < 0.01). Except for MUFA, differences in FA profiles among finishing systems were mostly mediated through their effect on IMF, even though the relationship of IMF with groups of FA differed among finishing systems. Under grain finishing, B. taurus had less SFA and greater MUFA than B. indicus (P < 0.01), but no differences were observed in PUFA (P > 0.05). With pasture-finishing, no differences were observed among the 2 genetic groups in SFA and MUFA (P > 0.05), but PUFA were decreased in B. taurus (P < 0.01). When genetic groups were compared in grain-finishing, B. taurus had a decreased ability for elongation and B. indicus had a decreased aptitude for desaturation of FA. On the other hand, with pasture-finishing a greater deposition of intermediate FA from ruminal biohydrogenation was observed in B. indicus than in B. taurus. Overall, FA profiles were affected more by finishing system in B. indicus than in B. taurus.