Lietuvos Vietin ė (Lithuanian Indigenous Wattle) Pig

Lietuvos vietin ė pigs were developed in Lithuanian ethnic lands following natu-ral selection and introduction of some imported pigs. Earlier, no purposeful selection was carried out for this old Lithuanian pig breed. Lietuvos vietin ė pigs as other local pig breeds are adapted to the specific local environment and could be fed with various locally available feedstuffs. So besides their genetic merit for agro-biodiversity, they represent the basis for sustainable local pork chains. The present chapter aims to present history and current status of Lietuvos vietin ė pig breed, its exterior phenotypic characteristics, geographical location, production system and main products from this Lithuanian autochthonous breed of pigs, one of the local pig breeds investigated in the project TREASURE. Moreover, a collection and review of available literature data, available until August 2017, on reproductive and productive traits of Lietuvos vietin ė pig breed were carried out. Reproductive and growth performance was estimated in different stages. Lean meat content was measured by ultrasonic equipment Piglog on the side of live pigs at the position of 12 ribs. Measurements of backfat thickness were taken with a ruler on the left side of carcasses at the dorsal line of the mid-back at the last rib and loin area at the 1/2 lumbar vertebra by digital camera EX-Z110 and afterwards were planimetrically measured by means of the “ SCAN-STAR K ” planimetrical system. Meat quality traits of the longissimus muscle were evaluated by means of pH at 45 min and 24 hours after slaughter.


History and current status of the breed (census)
The Lithuanian indigenous wattle (Lithuanian: Lietuvos vietinė) is a domestic pig native to Lithuania and is one of the oldest pig varieties in Europe. Census of Lietuvos vietinė pig breed is presented in Figure 1. Presently, there are only two registered farms of Lietuvos vietinė pigs with about 43 breeding sows and 11 boars in the latest available status (December 2017).

Exterior phenotypic characteristics
The Lietuvos vietinė pig breed morphology information is summarised in Table 1. It is a middle-sized breed with wattles under the neck, and usually large   black spots on the body, but colour variations include black and white, ginger, black and tricoloured (Figures 2 and 3). They have a friendly temperament. Being insensitive to the sun, these pigs are suitable for grazing. Previously in Lithuania some small farms kept pigs outdoor during warm season. The experiments showed that at 14.3-18.7°C air temperature the weight at 60 days of age outdoor-born piglets was 16.9-32.6% higher than that of indoor-born piglets. In individual and group enclosures with shelters, they consumed, respectively, 18.2-8.7% less feed than indoor piglets of Lietuvos vietinė breed. However, the loss of outdoor piglets until weaning, particularly in group enclosures, was by 8.0-8.5% higher than that of indoor piglets [11]. Nowadays, due to the African swine fever in wild boars and high veterinary standards for biosecurity, all domestic pigs in Lithuania should be kept strictly indoors. Consequently, the numbers of small pig farms and the numbers of local pigs have drastically decreased, because Lietuvos vietinė pigs are mainly intended for grazing. Currently, there is only a possibility for indoor rearing in semi-extensive conditions. Thus, Lietuvos vietinė pigs are kept, not for commercial purposes but for breed preservation and restoration and maintenance of herd stability by preserving biodiversity for future generations.

Organisations for breeding, monitoring and conservation
The activities for conservation of Lithuanian breeds were launched in 1994 when a minimal herd of Lietuvos vietinė pigs was formed at the Animal Science Institute, and thus their complete extinction has been prevented. Due to a small number of owners of Lithuanian local pigs, it is not possible to establish a separate association. Thus, Lithuanian Pig Producers Association is responsible for pig breeding. Researchers of Animal Science Institute of Lithuanian University of Health Sciences prepared the National Programme for the Conservation of Native Farm Animal Genetic Resources adopted by the Ministry of Agriculture of Lithuania in 1996 and 2008. The main purpose of these programmes was a collection, monitoring, investigation and conservation of Lithuanian local breeds in situ and ex situ. To achieve these goals, the National Farm Animal Genetic Resources Coordinating Centre was established at the Animal Science Institute at the end of 2008. Lithuanian Endangered Farm Animal Breeders Association (LEFABA) was established in 2010 ( Table 2).

Growth performance
The basic data on growth performance obtained in this review are presented in Tables 4 and 5. Due to big differences between studies with regard to the live weight range covered, we defined the stages for growth performance as lactation  (regardless of how long it was), growing stage (from weaning to approximately 30 kg live body weight), early and middle fattening stages estimated between approximately 30-60 kg and 60-100 kg live body weight, respectively. Sometimes, the source provided only the overall growth rate for the whole fattening stage (defined as overall) or even from birth to slaughter (defined as birth-slaughter, which is often calculated from the data given on live weight and age of pigs). It should also be noted that a big part of the collected studies simulated practical conditions of the production systems used and that only a smaller part of the studies aimed at evaluating the breed potential for growth. In the considered studies, daily gain in lactation period was approximately 230 g/day [7]. The average daily gain was 417 g/day in growing stage; 672, 588 and 644 g/day in early, middle and overall fattening stage [4,7]; and around 470 g/day from birth to slaughter [4][5][6][7], which indicates slower growth rate and lesser intensity of rearing in the Lietuvos vietinė pig breed. In the context of the evaluation of growth performance, it is also of interest to observe the extreme values, because it can be assumed that the maximum figures exhibit the growth potentials of Lietuvos vietinė pigs in ad libitum conditions of feeding (≈698 g/day in overall fattening stage [4]).  Lib  14  224  452  690  646  667  483   Rest  14  238  381  653  530  567  435 No. = number, ADG = average daily gain in g, Ad Lib = ad libitum feeding regime, Rest = restrictive feeding regime. 1 ADG in a period of lactation regardless of how long it was. 2 ADG in a growing period estimated from weaning to approximately 30 kg live body weight. 3 ADG in a period of fattening is reported for early and middle fattening stages estimated between approximately 30-60 kg and 60-100 kg live body weight, respectively. Sometimes, the source provided only the overall growth rate for the whole studied period (in that case defined as overall). No. = number, ADFI = average daily feed intake in kg/day, Ad Lib = ad libitum feeding regime, Rest = restrictive feeding regime, ME = metabolisable energy, CP = crude protein. 1 ADFI in a period of fattening is reported for early and middle fattening stages estimated between approximately 30-60 kg and 60-100 kg live body weight, respectively. Sometimes, the source provided only the overall growth rate for the whole studied period (in that case defined as overall). In considered studies, the information on feed intake and feed nutritional value were scarce, which limits the evaluation of growth potential. Average daily feed intake increased from 2.0 kg/day in early to 2.5 kg/day in middle fattening stage [7], whereas in the overall fattening stage, the average daily feed intake was 2.4 kg/day [4,7].

Meat quality
The basic data obtained in this review with some of the most commonly encountered meat quality traits measured in the longissimus muscle that could be found are presented in Table 7. In the studies reporting meat quality of Lietuvos vietinė pigs, pH measured in the longissimus muscle at 45 min and 24 h postmortem were 6.3 [7] and 5.4 [7,9], respectively. The intramuscular fat content varied from 1.7 to 3.5% [7,9], and colour measured in CIE L*, a* and b* colour space  was approximately 55, 15 and 7.6 for L*, a* and b*, respectively [7]. The longissimus muscle from Lietuvos vietinė pigs has lower contents of cholesterol (39.6 mg/100 g [7]) than those of lean conventional hybrids (44.24 mg/100 g).

Use of breed and main products
Due to the high fatness of Lietuvos vietinė pigs, implemented SEUROP grading system for carcass evaluation in abattoirs and import of cheap surplus meaty cuts of carcasses, Lietuvos vietinė pigs are not competitive on the market. Thus, their number is not increasing. Most of Lietuvos vietinė pigs are slaughtered and processed in the conventional pig production chain. Due to veterinarian restrictions related to the African swine fever, people refuse to keep growing pigs up to bacon condition for self-supply, although this was a common practice in the past among the people of the countryside. Most of the Lietuvos vietinė pigs from nucleus herd are used in the common pig production chain, whereas only the small part of pigs is being used for the production of home-made products. The traditional Lithuanian pork products produced are smoked backfat, including salt-cured backfat in the southeastern part of Lithuania, smoked hams and bellies, loins and different fresh and smoked dry sausages. The amount of unused carcass parts from Lietuvos vietinė pigs is small because Lithuanian cuisine knows different dishes not only from lean and fat pork but also from the offal, like meat jelly, blood pudding, liver pate and others.   Table 7.
Summary of collected literature data on meat quality in the Lietuvos vietinė pig breed.