The role of mitochondrial DNA to determine the origin of domestic chicken

Mitochondrial DNA (mtDNA) is has recently lost relevance especially when utilised to study species that are characterised with a history of several migrations. Nonetheless, mtDNA can still represents a useful additional tool in the study of molecular genetic diversity. The reason for the adoption of mtDNA is that it is easy to amplify because it appears in multiple copies in the cells and the mitochondrial gene content is strongly conserved across generations. Thousands of published studies have reached conclusions about population history, patterns of gene flow, genetic structure, and species limits, on the basis of mtDNA sequence variation. MtDNA has been used to study phylo-geographic structure of avian species, and to identify the number of maternal lineages and their geographic origins. Most studies of chicken mtDNA rely on sequences of partial control region but recent researches used the complete mtDNA genome to reconstruct the history of animal domestication. The first genetic study on mtDNA suggests that the Indochinese Red Junglefowl subspecies Gallus gallus gallus is the primary ancestor of the domestic chicken (Gallus gallus domesticus). Other studies showed that at least three subspecies of Gallus gallus were enrolled in the origin of domestic chicken breeds, and that there may be at least two domestication centres: one in Southeast Asia and one in the Indian subcontinent. The authors suggested nine highly divergent clades (named clade A-I) related to geographical distribution in a wide range of domestic chickens and Red Junglefowls across Eurasian regions. Understanding when chickens were transported out of domestication centres and the directions in which they were moved provides information about prehistoric human migration, trade routes and cultural diffusion. MtDNA has been used to infer regions of domestication and to identify the number of maternal lineages and their geographic origins in macroevolution studies.peer-reviewe

morphological and genetic characterisation of pagliarola breed and its genetic relationships with other three indigenous italian sheep breeds

Sheep are an important livestock species in the socio-economic contest around the world. In the past, exotic sheep breeds were utilised in crosses with local breeds in order to improve their production traits. The Pagliarola is an ancient sheep population spread over many areas of the central Italy, mainly in Abruzzo region. The aim of this paper was to identify this breed from other sheep breeds living in the same area trough morphological and genetic characterisation. Fifty-three Pagliarola sheep animals (two flocks) were sampled together with 30 sheep of Appenninica, Gentile di Puglia and Merinizzata Italiana. Biometrical measures and 25 microsatellite markers were studied for the characterisation. In the morphological analysis, the Pagliarola was observed to be well separated from the other breeds and the genomic results confirmed the morphological study. In the molecular approach, a total of 330 alleles were detected. In the neighbour-Net tree, each breed clustered independently and no clear cluster was observed. The expected heterozygosity was the highest in Appenninica (0.78), while Pagliarola had the lowest (0.70). Results of STRUCTURE analyses at K=5 showed Pagliarola breed splitted in two sub-clusters. Both biometric and molecular results allow to consider the residual Pagliarola as an original genotype. Moreover, the variability still remaining in this population can be useful to plan suitable conservation programs

ICT capital and labour productivity growth: A non-parametric analysis of 14 OECD countries

This paper uses a new set of country data for 14 countries, members of the OECD, and a non-parametric approach to provide new evidence on the impact of Information and Communication Technology (ICT) on labour productivity growth between 1995 and 2005. For the first time, in the present paper a bootstrap approach for the decomposition of labour productivity change, proposed by Kumar and Russell (2002), is employed. This approach permits to conduct statistical inference on the parameters of interest, and to analyse the effects of ICT technologies on capital accumulation. The results confirm the role of ICT as a general purpose technology that needs organizational and business process changes to fully exploit its growth opportunities. The paper also finds out, by applying a non-parametric test, that ICT technologies positively contribute to the generation of convergence clubs in the evolution of labour productivity. Finally, the empirical evidence offers some basic guidance for future policy intervention in supporting ICT capital investments

Origin and complete breed standard of Maltese black breed

This review is a first attempt to give a comprehensive historical account on the evolution of the Maltese Black chicken breed. The initiative consolidates available information to propose hypothesis on the origins of the breed, and to develop a comprehensive breed standard in conformity with the format of the American Breed Standard. The Maltese Black was established in 1950 as a rustic, dual purpose breed capable of producing adequate egg and chicken for consumption. In the 1960's, it was replaced with commercially available stock, marginalising the breed and restricting its existence to small dispersed populations. An initial attempt to have an in-situ conservation of the Maltese Black started in 1998 with a small flock of about 400 chickens that were later relocated to the Agricultural Research and Development Centre in Malta with the intention of maintaining a nucleus flock as a measure for a long term ex-situ conservation strategy. A recent survey highlights that the present population has drifted significantly away from standards first published in 1950. In efforts to consolidate the breed standard definition of the Maltese Black, the breed standards of related Mediterranean breeds, as confirmed by molecular markers, were consulted to translate and address the missing gaps in the previous breed standards. The updated breed standard presented will act as the bench mark against which all future breeding and selection programs are compared.peer-reviewe

ICT capital and labour productivity growth: A non-parametric analysis of 14 OECD countries

This paper uses a new set of country data for 14 countries, members of the OECD, and a non-parametric approach to provide new evidence on the impact of Information and Communication Technology (ICT) on labour productivity growth between 1995 and 2005. For the first time, in the present paper a bootstrap approach for the decomposition of labour productivity change, proposed by Kumar and Russell (2002), is employed. This approach permits to conduct statistical inference on the parameters of interest, and to analyse the effects of ICT technologies on capital accumulation. The results confirm the role of ICT as a general purpose technology that needs organizational and business process changes to fully exploit its growth opportunities. The paper also finds out, by applying a non-parametric test, that ICT technologies positively contribute to the generation of convergence clubs in the evolution of labour productivity. Finally, the empirical evidence offers some basic guidance for future policy intervention in supporting ICT capital investments

Genetic diversity in four populations of Nguni (Zulu) sheep assessed by microsatellite analysis

Zulu sheep are found mainly in the rural KwaZulu-Natal province and the numbers are declining due to indiscriminate inbreeding. There is thus a need for phenotypic and genetic characterisation as a first phase for planning conservation strategies. Zulu sheep populations sampled were from Makhathini research station (MS) (n=33), University of Zululand (UZ) (n=21), a community at KwaMthethwa (KM) (n=32) and from Msinga (EM) (n=33). One European breed Appen - ninica (AP) was used as out group. Microsatellite analysis using 29 microsatellite loci was used in this study. Among the Zulu sheep, the mean number of alleles per locus was the lowest (3.86) in UZ and the highest (6.24) was realised in EM. The mean values of observed and expected heterozygosity were 0.57 and 0.61, respectively. Neighbour-joining tree showed two main Zulu sheep clusters: the UZ, KM and MS sheep populations clustered together and the second cluster included only representatives from the EM population. The STRUCTURE analysis showed that KM, AP and EM were founded in separate clusters, whereas UZ and MS clustered together. The study demonstrated that there was a common origin of the population from the research stations (MS and UZ populations). It also demonstrated that the EM had a different history for the other three populations. This work suggests that exchange of rams could be useful in reducing inbreeding when considering conservation breeding programmes

Autopsy findings of fatal retroperitoneal hemorrhage after traumatic rupture of bilateral renal angiomyolipoma

the present work reports the autopsy findings of a unique case characterized by fatal retroperitoneal hemorrhage following the traumatic rupture of bilateral renal angiomyolipomas. renal angiomyolipomas are generally benign tumors with an unpredictable clinical course, ranging from asymptomatic to sudden rupture and hemorrhagic shock. they may be associated with genetic disorders such as tuberous sclerosis complex. the case under investigation is unprecedented in the medical literature due to its bilateral nature and fatal outcome. autopsy analysis revealed an extensive retroperitoneal hemorrhage originating from bilateral ruptured tumors. microscopic examination found features consistent with bilateral renal angiomyolipoma. circumstantial information identified a traffic accident before the death, considering it as the cause of the tumors' traumatic rupture. In this case, due to the severity of the situation, immediate medical measures-such as fluid resuscitation, coagulopathy correction, and surgical treatment, which are usually lifesaving-could not be performed. this led to the patient being declared dead at the scene of the crash

Genomic variability of Cirneco dell’Etna and the genetic distance with other dog breeds

Cirneco dell’Etna is an old Italian breed of scent hunting dogs. Commonly used genomic measures such as heterozygosity, fixation indexes, and runs of homozygosity can help to improve knowledge about its genetic diversity. This study aimed to: (i) investigate Cirneco’s genomic background, (ii) quantify its genomic inbreeding, and (iii) detect genomic regions differentiating the Cirneco’s two allowed coat colours, self-coloured fawn and tan and white. Canine 230K SNP BeadChips was used to investigate 24 Cirneco (19 self-coloured fawn, and 5 tan and white) and other 106 dogs from eight phylogenetically and historically related breeds. The genetic distance, ancestry, and relationship among breeds were explored by multidimensional scaling, Reynolds distances, phylogenetic tree, and admixture analysis. The genomic inbreeding (FROH) was calculated for each breed. Averaged Wright’s fixation index FST was used to identify the genes that most differentiated the two groups of Cirneco. All analyses highlighted that Segugio Italiano and Kelb tal Fenek are the closest breeds to Cirneco. Within the breed, tan and white subjects showed a more heterogeneous genetic background and a lower inbreeding in comparison with self-coloured fawn ones, even though more than half of the latter presented a superimposable admixture. The gene that most differentiated these two groups is Microphthalmia-Associated Transcription Factor (MITF), previously associated with white spotting in other breeds. Given the small size of the Cirneco population and its open registry, its management should carefully combine morphological and genealogical evaluations with genetic tools to identify the best breeders while maintaining an acceptable genetic pool.peer-reviewe

Genetic diversity of Cornigliese sheep breed using STR markers

To preserve sheep biodiversity is an important issue as the most productive breeds are becoming dependent on intensive management and breeders are abandoning the traditional breeds. The Cornigliese sheep is a local breed from Parma Apennine. In the last centuries it was crossed with Merino and Bergamasca breeds. The aim of this work is to investigate the genetic variability in the Cornigliese breed using 27 microsatellite markers. A total of 144 individual blood samples were randomly collected from the following breeds: Cornigliese, Bergamasca, Appenninica and Spanish Merino. The Palmera breed was used as out-group. A total of 344 alleles were detected. The average expected heterozygosity ranged from a maximum of 0.77 in Appenninica to a minimum of 0.68 in Bergamasca. In general,Cornigliese showed heterozygosity estimates less than expected. The Reynolds weighted genetic distance among the breeds highlighted a clear cluster, including Cornigliese and Bergamasca. As expected, they appeared in close neighbourhood in the tree because of the historic crossbreeding practices between these two breeds. Results of STRUCTURE analyses show that the four studied breeds were discriminated into separate clusters, even if Cornigliese has some individual related to Bergamasca and Spanish Merino. This work confirmed the historical information about the origin of Cornigliese breed which reports gene flow among these breeds. The genetic parameters show a moderate value of inbreeding in Cornigliese and therefore this breed should be monitored due the low number of individuals that compose it

Mitochondrial diversity of Yoruba and Fulani chickens: A biodiversity reservoir in Nigeria

Poultry are the most widely distributed type of livestock in Nigeria. Indigenous chickens are extremely common throughout the country. Indeed, approximately 83 million chickens are raised in extensive systems and 60 million in semi-intensive systems. To provide the first comprehensive overview of the maternal lineages in Southwest Nigeria, we analyzed 96 mitochondrial DNA control region sequences from 2 indigenous chicken ecotypes: Fulani and Yoruba. All samples belonged to the most frequent haplogroup (E) in Africa and Europe and showed noticeably low haplotype diversity. Although only 11 different haplotypes were detected, with 2 of them never found before in Nigeria, the presence of unique sequences among our indigenous samples testified to their status as an important genetic resource to be preserved. Furthermore, a total of 7,868 published sequences were included in the comparative analysis, which revealed an east-west geographic pattern of haplogroup distribution and led to the conclusion that the gene flow from Southeastern Asia mainly involved one mitochondrial clade. Moreover, owing to the extensive genetic intermixing among Nigerian chickens, conservation efforts are required to safeguard the extant mitochondrial variability in these indigenous ecotypes and establish future improvement and selection programs