Elisa Mazzanti

Demographic genetics of the endangered Amiata donkey breed

Abstract The demogenetic structure of the Amiata donkey, an endangered breed from Central Italy, was investigated using information from pedigrees. Genealogical data of 602 donkeys reared in Tuscany were recorded in a database and analysed by the computer package ENDOG. Population size increased from 89 subjects in 1995 to 503 (129 males and 374 females) in 2005. Animals were distributed among 152 herds, but the effective number of herds was 21, suggesting that a small number of herds provided stallions for the entire breed. The maximum number of traced generation was 4, the mean maximum generation was 1.14, the mean complete generation was 0.53, and the mean equivalent generation was 0.78. The average relatedness coefficient (AR) in the 503 alive animals was 0.94% while the mean F was 0.29% so the effective population size was 172.41. Among 24 animals with a 4-generation history, 3 (12.5%) were 25% inbred. Although the incompleteness of genealogical information did not permit accurate inference of the current values of population genetic parameters, the present work represents a first step towards an efficient management of the breed.

The genetic variability analysis of the Amiata donkey breed by molecular data

This study presents the results of the genetic characterization of the Amiata donkey breed using STR markers. A total of 18 microsatellite loci were analysed in 50 unrelated individuals reared in Tuscany and in Lazio (34 and 16 animals respectively). The average number of alleles per locus was moderate (5.61±2.893), ranging from 2 (ASB02) to 13 (HTG7). Mean observed heterozygosity was 0.579, whereas mean expected heterozygosity was 0.609. Six markers showed a significant (P?0.01) deviation from the Hardy-Weinberg proportions. The average similarity values within the two groups were 0.523 ± 0.020 for animals reared in Tuscany and 0.458 ± 0.016 for those reared in Lazio (total average similarity 0.489 ± 0.019) while inbreeding coefficients were respectively 0.440 and 0.390.

A colony of dog guides: analysis of the genetic variability assessed by pedigree data.

Abstract The study presents the analysis of the genetic variability in a colony of dog guides. Three breeds, Labrador (L), Golden Retriever (GR), and German Shepherd (GS), were evaluated. Pedigrees data on 370 L, 260 GR, and 85 GS dogs bred for guideby the National Guide Dog School (SNCG) of Scandicci (Florence, Italy) were used. Data were available beginning from 1994. The average coefficient of coancestry and the mean F were 0.8% and 0.45% in GR, 0.7% and 0.38% in L, 1.0% and 0.49% in GS, respectively. The rate of increase in inbreeding was lower in L population (0.17) than in GR population (0.54), while in GS only the dogs with 5 e 7 traced generations resulted inbred. The results of this research point out that the genetic management of the dogs seems to be carefully and rationally monitored. Nevertheless, the population that may require a greater attention seems to be the GR, where a higher increase of the coefficient of inbreeding per generation is observed; therefore, the importation of germplasm from other working dogs is desirable in order to avoid in future an excessive increase of the inbreeding that could lead to adverse consequences for dogs health and fertility.

Morphological characterization of the Amiata donkey breed through the data reported in the Anagraphic Register

abstract The Anagraphic Register of the Amiata donkey breed has been established in 1993, and is maintained by the association of breeders of the Grosseto province (APA-GR). Being an endangered breed, subjects with unknown pedigree have been allowed to be recorded, provided that females scored at least 60 and males at least 75 points on morphological evaluation. Recording is still open for females, whereas it has been closed in 1997 for stallions. In the present work, we have investigated the morphological structure of the Amiata donkey through the data reported in the Anagraphic Register. This last was started recently and was maintained on paper only, meaning that it inevitably includes a certain degree of incompleteness. The morphological records of 74 unrelated Amiata donkeys (62 females and 12 males) were collected at the APA-GR in 2005. For each animal the following biometrical data was available: 10 individual scores (from 1 to 10) for coat colour, head shape, neck, withers, shoulders, back, back-lumbar line, limbs and plumbs, walking and foot, evaluated by certificated experts of the breed; in addition, measurements of withers height, chest and cannon circumference were individually reported. As an index of body compactness, the ratio chest/cannon circumference was calculated from data. One-way analysis of variance was used to test the differences between male and females for total scores and morphological measurements. Data were analysed by JMP software version 5.0 of SAS Inst. (2002). No significant differences were observed among females and males: Mean (± s.d.) withers height (WH) were 129.0 ± 3.2 cm in females and 131.8 ± 3.1 cm in males. Chest circumference (CH) were 148.4 ± 5.1 cm and of 150.8 ± 5.5 cm, for males and females respectively, and cannon circumference (CC) were 16.6 ± 1.2 cm and 17.1 ± 0.4 cm, for males and females respectively. The ten evaluation scores were added up for each animal; means were 72.4 ± 6.2 in females (range 61-88) and 77.2 ± 3.0 (range 71-80) in males. The ratio CH/CC, an index of body compactness, was 0.11 ± 0.01 in males (range 0.11-0.12) and 0.11 ± 0.01 in females (range 0.09-0.13). All these measurements indicate low variability among individuals as well as limited sexual dimorphism.

Haplotype association analysis of meat quality traits at the bovine PRKAG3 locus

Abstract The current study presents the results of a preliminary haplotype association analysis at the bovine PRKAG3 locus with meat quality traits in the Chianina breed. No significant association was shown between haploid haplotypes (or diplotypes) and phenotypical traits after applying a Bonferroni correction for multiple comparison. Nonetheless, data from Longissimus dorsi muscle suggest the presence of a statistically non-significant trend toward an influence of the PRKAG3 haploid haplotypes on meat colour (a*) and water holding capacity (M/T) traits, as confirmed also by diplotype-based association analysis. A less clear set of results was observed for the Triceps brachii and Semitendinosus muscles.

Beef traceability using molecular methodologies

Over the last decade, the problem of assigning an individual to its source population has become more and more important. Breed names are increasingly being used as brand names, and this has stimulated interest by the beef industry in developing techniques to certify breed origin of beef products. Among these, DNA-based methods are particularly useful considering that genetic material represents a stable code able to preserve information about the subject and its origin. The aim of this work is to develop an efficient methodology of breed traceability based on microsatellite markers (Ciampolini et al., 1995). We also consider a second methodology based on the research of possible breed-specific polymorphisms in target genes. Since coat colour is a characteristic subjected to selection over many years, genes that influence this phenotype could be potential markers able to distinguish between different breeds (Girardot et al., 2005). The main coat colour genes have been analyzed for Chianina, Marchigiana, Romagnola and Piemontese.

Genetic variability of three local cattle breeds (Calvana, Pontremolese, Garfagnina) by STR analysis

Abstract The dramatic size contraction of local cattle breeds due to replacement with cosmopolite improved breeds highlights the need for native genetic resources conservation. In 1985, the Anagraphic Register of local cattle breeds and small-size ethnic groups was established by the Italian Ministry of Agriculture and Forestry. Calvana, Pontremolese and Garfagnina are among the included breeds. They are all native from Tuscany. Present breeding area covers the provinces of Firenze, Prato, Pistoia and Siena for the Calvana breed (around 280 heads), while it is restricted to the province of Lucca for both Garfagnina (around 180 heads) and Pontremolese. This latter breed consists, nowadays, of less than 40 heads, while being around 15000 in 1940s. The characterization of the genetic structure and variability via molecular markers could provide useful information for breed management and conservation. In the present study, a total of 149 animals, evenly distributed among the three breeds, were genetically characterized by using 22 STR markers located on 13 different chromosomes. Among these, ten (BM1818, BM1824, ETH10, ETH152, ETH3, HEL9, ILST006, INRA63, TGLA126, TGLA227) belonged to the panel of 30 microsatellites recommended by the ISAG-FAO Working Group on domestic animal diversity. Mean number of alleles per locus in the total sample was 9.9, ranging from 5 (ETH10) to 14 (BMS690, HEL9, ETH152). Within population mean number of alleles did not vary among the three population samples (range, 6.4 to 6.8). On the other hand, almost all loci showed several low frequency alleles “private” to one breed only. Mean locus heterozygosity in the total sample was 0.426. All loci showed a significant excess of homozygous genotypes in all the three breeds. Only the HEL9 locus (BTA8) was characterized, in all breeds, by a significant excess of heterozygous genotypes. Average FIS over all loci was 0.287 for Garfagnina, 0.378 for Calvana, and 0,479 for Pontremolese. Significant pair-wise linkage disequilibrium (or gametic imbalance, for unlinked loci) was observed for all breeds. In particular, more than 40% of all possible pair-wise comparisons were in linkage disequilibrium in the Pontremolese breed. A breed assignment test based on a log-likelihood approach allowed the correct allocation of 100% of individuals to their true breed of origin.

The genetic resistance to gastro-intestinal strongylids in Appenninica sheep: relationship among parasitical load and haematological parameters

Abstract Faecal Egg Count (FEC) is generally considered a simple but effective parameter for estimating resistance to strongylids, due to its phenotypic relationship to the total number of parasites present in the animal. Nevertheless, also haematological indicators have been shown to be useful in measuring gastro-intestinal nematode resistance in sheep, such as Packed Cell Volume (PCV), number of leukocytes, proportion of eosinophils and plasma albumin. The study was conducted in a single herd of Appenninica sheep situated in Tuscany (Italy) with the aim of studying the relationship among parasitic load of gastro-intestinal Strongylids and haematological parameters. Faecal samples from 54 sheep were collected in four different withdrawals (April, May, September and November 2004) and analysed in order to determine parasite EPG (Eggs Per Gram), using the McMaster technique. At the same time as the faecal samples, blood samples were also collected in order to determine PCV, total proteins, complement proteins, plasma albumin, erythrocytes and eosinophils. Considering the low infection level in spring (April and May), it was believed that animals with a positive EPG in this season could already be considered “not resistant”, although a limited infection (EPG<200) might serve as an index of host’s capacity to keep the parasite population under control. Consequently, we defined as “resistant group” (RG) the subjects with an average value in the spring sample equal to zero EPG, “intermediate resistant group” (IRG) the subjects with an average value under 200 EPG and “not resistant group” (NRG) the animals with an average value over 200 EPG. NRG subjects always showed lower values of PCV (an indicator of anaemia) than the other groups. In September, NRG subjects also showed significantly lower values of eosinophils (3.28%) compared to the other groups (6.54 and 6.20%, respectively, for IRG and RG, P<0.01) and higher values of complement (20.06 vs. 12.61 and 12.77, respectively, for IRG and RG, P<0.05). On the contrary, in November, NRG subjects showed lower values of complement (7.78) than the other groups (19.00 and 15.23, respectively, for IRG and IR, P<0.01).

Leccese local sheep breed from Apulia: evidence of genetic substructuring from STR loci

The Italian Bracco is one of the oldest pointing dog breed, used for hunting ever since the Renaissance time; paintings of the 14th century show hunting sceneries with dogs similar to the present day Bracco. The breed has been officially registered by ENCI (the Italian cynological club) in 1949, when the definitive standard was established. In this work, we report the first results of a study aimed at measuring morphological traits in this breed, as a part of a more comprehensive study whose objective is to identify the characters that have the potential of being genetically improved. R. Ciampolini1, F. Cecchi1, A. Bramante1, F. Casetti2, S. Presciuttini1

Associations Between Microsatellite Markers and Milk Traits in Massese Sheep: Preliminary Results

Carnitine is a small essential molecule that regulates the substrate flux and energy balance across cell membranes by modulating both the transport of long-chain fatty acids into mitochondria and their subsequent β-oxidation. Although humans are capable to synthesize it endogenously, approximately 75% of body carnitine sources come from diet and particularly from food of animal origin such as meat, poultry, fish and dairy products. Due to its intrinsic interaction with the bioenergetics processes, carnitine plays an important role in diseases associated with metabolic compromise, especially mitochondria-related disorders. It has been reported that administration of carnitine by diet or at pharmacological doses can have significant benefit in several physiopathological situations such as ischemia, myocardial injury and neurodegenerative diseases, but there is no data on the possible protective role of carnitine against other oxidative stress-induced pathologies associated with an altered chromosome stability such as cancer. Therefore, we analysed the potential capability of carnitine to protect mammalian cells from genetic instability induced by H2O2, using Chinese Hamster Ovary (CHO) cells as a mammalian cell model having a stable karyotype and the chromosome aberration test as genetic end point. Our results showed that in the absence of carnitine H2O2 induced a high and dose-dependent induction of structural chromosome aberrations in the concentration range 0.1-0.4 mM whereas at the same H2O2 doses, a pre-treatment with 4 mM carnitine produced a strong decrease either of the percent of cells with aberrations or of the aberration frequency. The observed carnitine-mediated prevention of H2O2-induced chromosome aberrations reaches almost the control value in the cultures treated with 0.1 mM of H2O2 thus evidencing a reduction of about 70%. These data, together with preliminary results showing that carnitine is not able to protect cells from the inhibition of cell growth caused by H2O2, suggest that carnitine protects mammalian cells from H2O2–induced clastogenic damage and this effect is reproducible and highly specific.