**2. Haematological pattern of Apulian native sheep breeds**

In Apulia, the region covering the heel of the boot-shaped Italian peninsula, the rather harsh conditions of the soil and climate and the selective pressure of endemic haemotropic parasites have yielded genetic pools that are generally rustic and tolerant to the diseases caused by haemotropic parasites. An evaluation of the local genetic resources to explore their potential for sustainable and profitable genetic development programs is based on the knowledge of the physio-pathological features of blood according to species, breed and animal.

#### **2.1 The Apulian sheep native breeds**

Altamurana and Leccese, the latter also known as Moscia Leccese, are two ancient dairy breeds native to Apulia whose origins are not fully known. It is thought that they developed from an Asian breed, particularly from a Zackel type stock. They are rough wooled, well suited to life in harsh and semiarid conditions and they make good use of marginal pastures. Both breeds are seriously endangered. Though not as endangered as the former two breeds, Gentile di Puglia sheep may be considered, according to Alderson (2009), at risk of extinction because of their numerical scarcity and population trends. Yet, the Gentile di Puglia is classified as one of the main fine-wooled ovine breeds. The origin of the breed can be traced back to ancient Roman times when the soft fleece of an Apulian sheep, the Tarentine breed, was used to make the *togas* of important Roman citizens. According to William Youatt (1867), the Tarentine breed "had gradually spread from the coast of Syria and the Black Sea, and had now reached the western extremity of Europe. Many of them mingled with and improved the native breeds of Spain, while others continued to exist as a distinct race; and, meeting with a climate and a herbage suited to them, retained their original character and value, and were the progenitors of the Merinos of the present day."

#### **2.2 Adult haematological pattern**

Table 1 has been compiled from the existing repertoire of haematological values obtained analysing the blood of Apulian sheep; it reports least-square means (LSM) and standard error (SE) of haematological data obtained by analysing blood samples collected in population surveys of Gentile di Puglia and Leccese (Pieragostini et al., 1994; Pieragostini, 2006). Samples for Altamurana sheep were obtained from 58 purebred ewes ranging from 2- 6 years of age and bred on an experimental farm near Bari (Pieragostini et al., 1999). Comparison with the literature (Jain, 1993), where range and medians are available, is also shown. On the basis of the normal probability plot, our data appear to follow a normal distribution where the median equals the mean.

When compared to normal blood values for sheep in the literature (Greenwood, 1977; Jain, 1993), the blood of Apulian sheep appears to be characterized by fewer erythrocytes that are normal in size and have higher haemoglobin content. This phenomenon typically seems to reflect a Mediterranean/North-African ovine blood picture (Pieragostini et al., 1994). The decreased PCV values correspond to lower blood viscosity and thus greater availability of water, which seems to be of particular adaptive significance in habitats characterized by an arid climate like Apulia (Ariely et al. 1986). The fact that some blood factors are related to the suitability of the breeds under particular environmental conditions was suggested long ago (Cresswell & Hutchings, 1962).

In Apulia, the region covering the heel of the boot-shaped Italian peninsula, the rather harsh conditions of the soil and climate and the selective pressure of endemic haemotropic parasites have yielded genetic pools that are generally rustic and tolerant to the diseases caused by haemotropic parasites. An evaluation of the local genetic resources to explore their potential for sustainable and profitable genetic development programs is based on the knowledge of the physio-pathological features of blood according to species, breed and

Altamurana and Leccese, the latter also known as Moscia Leccese, are two ancient dairy breeds native to Apulia whose origins are not fully known. It is thought that they developed from an Asian breed, particularly from a Zackel type stock. They are rough wooled, well suited to life in harsh and semiarid conditions and they make good use of marginal pastures. Both breeds are seriously endangered. Though not as endangered as the former two breeds, Gentile di Puglia sheep may be considered, according to Alderson (2009), at risk of extinction because of their numerical scarcity and population trends. Yet, the Gentile di Puglia is classified as one of the main fine-wooled ovine breeds. The origin of the breed can be traced back to ancient Roman times when the soft fleece of an Apulian sheep, the Tarentine breed, was used to make the *togas* of important Roman citizens. According to William Youatt (1867), the Tarentine breed "had gradually spread from the coast of Syria and the Black Sea, and had now reached the western extremity of Europe. Many of them mingled with and improved the native breeds of Spain, while others continued to exist as a distinct race; and, meeting with a climate and a herbage suited to them, retained their original character and value, and were the progenitors of the Merinos

Table 1 has been compiled from the existing repertoire of haematological values obtained analysing the blood of Apulian sheep; it reports least-square means (LSM) and standard error (SE) of haematological data obtained by analysing blood samples collected in population surveys of Gentile di Puglia and Leccese (Pieragostini et al., 1994; Pieragostini, 2006). Samples for Altamurana sheep were obtained from 58 purebred ewes ranging from 2- 6 years of age and bred on an experimental farm near Bari (Pieragostini et al., 1999). Comparison with the literature (Jain, 1993), where range and medians are available, is also shown. On the basis of the normal probability plot, our data appear to follow a normal

When compared to normal blood values for sheep in the literature (Greenwood, 1977; Jain, 1993), the blood of Apulian sheep appears to be characterized by fewer erythrocytes that are normal in size and have higher haemoglobin content. This phenomenon typically seems to reflect a Mediterranean/North-African ovine blood picture (Pieragostini et al., 1994). The decreased PCV values correspond to lower blood viscosity and thus greater availability of water, which seems to be of particular adaptive significance in habitats characterized by an arid climate like Apulia (Ariely et al. 1986). The fact that some blood factors are related to the suitability of the breeds under particular environmental conditions was suggested long

**2. Haematological pattern of Apulian native sheep breeds** 

animal.

of the present day."

**2.2 Adult haematological pattern** 

ago (Cresswell & Hutchings, 1962).

distribution where the median equals the mean.

**2.1 The Apulian sheep native breeds** 


Table 1. Least-square means (LSM) and standard error (SE) of haematological data from adult animals belonging to native Apulian sheep breeds. RBC, Red Blood Cells; Hb, Haemoglobin; PCV, Packed Cell Volume; MCV, Mean Corpuscular Volume; MCH, Mean Corpuscular Haemoglobin, MCHC, Mean Corpuscular Haemoglobin Content; WBC, White Blood Cells; N, Number of animals.

Comparison of the data in table 1 shows that the haematological patterns in the three breeds are broadly the same. Gentile sheep seem to exhibit slight differences from the other two breeds, particularly as to the erythrocyte count, the mean corpuscular volume (MCV) and the mean corpuscular haemoglobin (MCH); in fact they are apparently the most European among the three. The traditional breeding sites of Gentile and Leccese differ substantially; one is in the southern part and the other in the northern part of Apulia, which is 500 Km long extending from the 39° to the 42° parallel. The Altamurana breeding site is in the Murgia uplands, in the central portion of Apulia. Its location in a rather harsh environment, together with the common origin of the two breeds, may account for the fact that Altamurana is closer to Leccese than to Gentile (Tab.1). However, a non-negligible point is that the physiological pattern characterizing the Altamurana and the Leccese breeds differs considerably from that of the Gentile di Puglia, as they belong to the group of dairy breeds while the Gentile is a fine wool and meat-producing sheep.

#### **2.3 Lamb haematological pattern**

Although the paucity of data in the literature concerning the haematological picture of lambs is scarce, general and particular information is available on the developmental pattern of their haematological values. The development of haematological picture of Altamurana lambs was investigated to assess the normal blood parameters and check the first occurrence in the blood smears of endemic endoerythrocytic parasites (Pieragostini et al., 2000). Standard haematological values were calculated for 22 Altamurana lambs controlled from birth to 18 months of age The values recorded in the neonatal period were strongly affected by birth weight. As clearly shown in table 2, the haemoglobin concentration (Hb), packed cell volume (PCV) and white cell count (WBC) exhibited significant age-dependent variations, particularly Hb % and PCV decreased while WBC increased.

Over weeks 1-5, red cell indices mainly followed the same trends as the Hb and PCV. Over the first four months, the RBC values on average remained unchanged at approximately 9 million/l but then decreased. Starting from the fifth month, overall mean values were practically the same as in adults.

Tolerance to Tick-Borne Diseases in Sheep:

**3. Breeds and tolerance to TBD in Apulia** 

development of anemia in the face of infection.

endemic TBD.

sheep farms.

disease".

Highlights of a Twenty-Year Experience in a Mediterranean Environment 455

Tick-borne diseases are of global importance to human and animal health and welfare. They are also responsible each year for dramatic economic losses which comprise direct losses from death of animals, loss of productivity and indirect losses due to the costs of control measures. In 1979, the amount of losses were estimated to be globally USD 7 billion (McCosker, 1979), but several reports on the economic costs of specific tick-borne diseases indicated that the earlier report is an underestimate (Jongejan & Uilenberg, 2004). There is a wide portfolio of measures which could be used to control tick-borne diseases among which both husbandry practices and host-related factors such as age, innate tolerance and breed are of great importance. Breeds whose historical breeding site is situated under the latitude of 41° show the ability to thrive in areas where tick borne diseases (TBD) are common. This trait, which can be defined as tolerance to TBD, is associated with the ability to resist the

A review on host resistance to tick borne diseases is documented in cattle (Correia de Almeida Regitano & Prayaga, 2010). As for other species, the case of the tolerance to tickborne diseases shown by the sheep and horse native to Apulia is emblematic (Pieragostini & Petazzi, 1999; Rubino et al., 2006). In southern Italy, and particularly in Apulia, pyroplasmosis represents a longstanding and heavy burden for every type of livestock farm (Ceci & Carelli, 1999). Previous work performed on Gentile di Puglia sheep found that blood smears for parasite detection revealed an overall positivity rate of 93% for tick borne parasites (TBP) (Pieragostini et al, 2006). This high TBP positivity rate associated to normal blood values highlighted the tolerance of the native sheep towards TBP infection and accounted for

According to Townsend & Thirtle (2001), studies of the rates of return to research have usually been based on the implicit assumption that if there were no research, then there would be neither growth nor decline in output or productivity. In the case of livestock, particularly in those areas characterized by a sub-tropical disease ecology, the assumption is especially unreasonable. It ignores the losses that would have occurred in the absence of livestock health research, resulting in an underestimation of the rates of return. The financial impact of a range of clinical and subclinical diseases and mortalities on farms is difficult to assess because there are insufficient accurate survey data on their prevalence causes or production losses on a national basis. Thus demonstration of the economic advantage of animal health is one of the relevant issues in animal production. Pieragostini et al. (1996) carried out a four year study to check the economic and zoonotic importance of TBD on

To this purpose sheep belonging to breeds tolerant to TBD systematically underwent one prophylactic treatment with diminazene aceturate (Berenil, Hoechst, AG, Germany) in full spring before the mating season. Table 3 shows the results obtained. The comparison between the reproductive values in the treated sheep and in an untreated control group highlighted significant differences in fertility and fecundity, with the group of treated sheep that were more fertile and fecund. Pyroplasmosis, even though unapparent, represents an important cause of perturbation of animal welfare. The authors estimated relevant (30%) economic losses in non treated animals, thus defining pyroplasmosis as a "low income

**3.1 Tick borne diseases in Apulian native sheep: A low income disease** 


Table 2. Least-square means (LSM) and standard errors (SE) of haematological values recorded for 22 Altamurana lambs controlled from birth to 18 months of age. Modified from Pieragostini et al. (2000). RBC, Red Blood Cells; Hb, Haemoglobin; PCV, Packed Cell Volume; MCV, Mean Corpuscular Volume; MCH, Mean Corpuscular Haemoglobin, MCHC, Mean Corpuscular Haemoglobin Content; WBC, White Blood Cells.

Considering that reference data are mainly from breeds originally selected in northern European countries, when a comparison was made between 12 month-old Altamurana lambs and their northern counterparts, the erythrocytes of the Altamurana were fewer (7.5 *versus* 11.8 millions/l) but bigger (38.0 ft *versus* 26.5 ft) and full of haemoglobin (12.4 pg *versus* 9.3 pg). This is the same phenomenon encountered in Mediterranean/North-African ovine blood picture as well as in the native Apulian adults.

The overall pattern is suggestive of erythrocyte physiological effectiveness, which was confirmed by the perfect physical development of the subjects examined in this study. In the blood smears obtained at seven months of age, namely in full spring when lambs start to graze pastures, endoerythrocytic enzootic parasites (*Theileria* spp. and *Anaplasma* spp.) were recorded and then became a constantly occurring phenomenon as will be documented in the following sections.
