Ferruccio Petazzi

The relationship between the presence of extra α-globin genes and blood cell traits in Altamurana sheep

Additional α-globin genes in sheep might produce extra α-globin chains and, consequently, the subject carrying triplicated (ααα) or quadruplicated (αααα) haplotypes may exhibit different hematological phenotypes when compared to the normal duplicated (αα) homozygotes (NN). Both ααα and αααα heterozygous (ND) and ααα and αααα homozygous (DD) individuals were obtained by selection and inbreeding. Chromatographic RP-HPLC analyses of the globin chains of 65 subjects (15 DD, 20 ND and 30 NN) were performed. A highly significant linear regression (r2 = 0.967) of the α/β ratio on the number of α-globin genes was found, and the α/β ratio ranged on average from 1.0 in NN individuals to 1.2 in the ND and 1.6 in the DD subjects. Values for blood fell within the range of normality but were rather peculiar as a whole. When the erythrocytes of individuals carrying normal arrangements were compared with those of subjects with extra α-genes, the latter had fewer erythrocytes that were bigger in size and had a higher Hb content and a greater osmotic fragility. This hematological picture is consistent with the existence of an unbalanced α/β ratio.

Looking for prognosticators in ovine anaplasmosis: discriminant analysis of clinical and haematological parameters in lambs belonging to differently susceptible breeds experimentally infected with Anaplasma ovis

BackgroundA study was carried out to evaluate the response of different native sheep breeds to experimental infection with Anaplasma ovis, the most prevalent sheep tick-borne pathogen in Apulia (Southern Italy). Thirty-four lambs belonging to a Northern European breed (Suffolk) and two Southern Italian breeds (Comisana and Altamurana) were infected. Eleven clinical as well as haematological parameters were monitored at different temporal resolutions on the same subjects before and after the infection, resulting in a data set of 435 observations. The present work, aiming to further the research, presents the results of a multivariate analysis carried out to identify which parameters out of the eleven considered are the most reliable parameters to be considered as markers of the disease phenotype as well as prognosticators of practical clinical importance.ResultsData were analysed by discriminant analysis. Out of the eleven considered variables (red blood cells, packed cell volume, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin content, haemoglobin concentration, white blood cells, neutrophils, leukocytes, platelets, rectal temperature), only seven were included in the step-wise model since significantly increasing the Mahlanobis distance between the two closest groups. Both discriminant functions resulted to be highly significant (P < 0.0001) and the percentage of variation accounted for by the first discriminant function was 63.6% of the variance in the grouping variable.ConclusionsTaken together, the observed results stress the marked differentiation among the three breeds in terms of physio-pathological phenotypes indicating packed cell volume and red blood cell count as the most informative parameters in the routine clinical practice for A. ovis infection in sheep.

Tolerance to Tick-Borne Diseases in Sheep: Highlights of a Twenty-Year Experience in a Mediterranean Environment

The European landscape is characterised by a range of diverse farming systems. These relate not only to varied geographical environments and animal genetic resources, but also to different social and cultural contexts for farming and food production. This diversity is unique to Europe and, among the European countries, Italy is the home for a great variety of native breeds because of its complex orography and its long boot shape with very different climatic conditions from north to south. In the 1980’s, two of us moved from northern Italy to Apulia and soon came to appreciate the differences between the biotic and abiotic features of northern environment and the Apulian one. One of the most impressive differences were the enzootic tick borne diseases (TBD) and the related responses of the animals. As a consequence, much of our professional life has been devoted to the challenges posed by the diseases and to the study of the genetic peculiarities of native breeds both per se and in terms of their tolerance to TBD. This report is a review of the results obtained in a 20-year experience investigating the haematological features and tolerance to tick-borne diseases in Mediterranean native sheep breeds mainly Apulian native breeds compared to exotic breeds under various experimental conditions. In the wake of William Thomson (Lord Kelvin), a pioneer in thermodynamics and electricity, who said in 1891 that when you can measure what you are speaking about, and express it in numbers, you know something about it, but when you cannot measure it, your knowledge is of a meager and unsatisfactory kind, the central concept or research theme that guided all our research efforts stems from the notion that direct measurement of disease phenotypes and/or physiological features such as the hematological pattern provides a direct assay for measuring disease changes and the attitude of a genetic pool in facing disease. The work is concerned with the following main issues:  Haematological pattern of Apulian native sheep breeds  Breeds and tolerance to TBD in Apulia  Response to experimental anaemia  Response to Anaplasma ovis infection in experimentally infected sheep.

Impact of Mycobacterium avium subspecies paratuberculosis on profit efficiency in semi-extensive dairy sheep and goat farms of Apulia, southern Italy

A recent study on paratubercolosis in semi-extensive dairy sheep and goat farms in Apulia revealed a flock positivity of 60.5% and a seroprevalence of 3.0% for sheep and 14.5% for goat, with peaks of 50%. In such a context, providing detailed economic information is crucial for the implementation of a suitable control plan. In this paper we investigated the impact of Mycobacterium avium subspecies paratuberculosis (MAP) on profit efficiency of the Apulian dairy sheep and goat farms. Empirical results through a stochastic frontier model showed that the uninfected farms had a mean level of profit efficiency of 84%, which dropped to 64% in the presence of paratubercolosis as it negatively affected the productivity of feeding, veterinary and labour factors. Structural, managerial and production aspects were involved in the greater inefficiency of the infected farms compared to the uninfected ones: lower experience and schooling of farmers, no access to credit, fewer family members (women in particular) participating in the farming activities, high density of animals per hectare, small flocks, high number of goats in mixed flocks, no confinement practices for young and purchased animals and no pasture rotation. Hence, targeted interventions on these factors by decision makers can ensure effectiveness and efficiency to veterinary and economic action plans.

Relationships among functional markers, management, and husbandry in sheep: a Mediterranean case study

Most sheep farmers are aware of the importance of monitoring animal health and well-being for profitable sheep production. Unfortunately, there are only a few benchmarked functional measures of sheep well-being but much can be gained from our understanding of other species. Moreover, comprehensive monitoring programs may be complex and relatively expensive to implement. Hence, this work reports the results of a research study on the usefulness of functional markers in measuring dairy sheep well-being, taking into account farm management and environmental conditions. The study was conducted on 11 farms breeding Italian islander sheep breeds. The husbandry and management parameters of each farm were assessed and, based on the findings, the farms were scored in ascending quality order. Flock information concerned housing, milking system, pen size, grazing hours, health management, and stockmanship. Medical history, clinical data, the most relevant haematological, chemical and biochemical parameters, as well as the haemoglobin genotype were recorded for 415 individuals. The whole data-set was analyzed by Spearman correlation and multivariate statistical procedures, showing that albumin, serum alkaline phosphatase, haematocrit, and haemoglobin were the most significant functional markers of a flock’s general conditions. Haematocrit and haemoglobin reflect animal health status, while albumin and serum alkaline phosphatase are a measure of nutritional status and physical activity, respectively. These are objective parameters, which can be easily measured from blood samples and have proved to be effective for grouping to interpret animal well-being.

Reversible switch from hemoglobin A to C in sheep and recovery from anemia following experimental infection with Anaplasma ovis

Abstract Anemia causes a change in the type of circulating hemoglobin (Hb) in sheep carrying the βA-globin haplotype, where the Hb A is replaced with Hb C, unlike Hb B. The effect of the substitution of Hb A with Hb C on the recovery from anemia was investigated by comparing the hematological picture of sheep, following experimental infection with Anaplasma ovis.The blood values were obtained from 3 AB and 3 BB Hb sheep after the development of the disease where anemia is a pathognomonic symptom. The expression of the silent gene encoding for Hb C was detected by isoelectric focusing and quantified byhigh performance liquid chromatography Both Hb AB genotype and Hb C occurrence were involved in the lower recovery from anemia in the trial.

Measuring the profitability of theApulian native Altamurana ovine breedfor better conservation programmes

than that caused by recognized “enterohaemorrhagic” STEC serogroups such as O157 and O111. More widespread use of PCRor enzyme-linked immunosorbent assay-based screening tests for the presence of STEC of any serogroup in animal samples will undoubtedly result in increased detection of similar non-O157 outbreaks in the future. This will provide more accurate data on the epidemiology of human STEC disease.