An evaluation of the European pig diversity has been carried on by several countries, with the support of the European Union over the period of 1994 to 2000. This article presents an overview of the results of this investigation, focussing on two genetic marker techniques, namely microsatellites (MS) and amplification of fragment length polymorphism (AFLP). Nearly 200 loci were characterised on about 50 individuals from each of 59 to 71 breeds, according to the marker considered. The analysis of diversity, based on genetic distances, led to similar conclusions for the two marker types (MS and AFLP), in spite of a markedly lower total diversity of AFLP compared to MS. The analysis of the MS loci showed that the allelic diversity pattern among breeds was quasi-independent from the diversity pattern based on allele frequencies. Genetic distances showed no particular clustering of local with international breeds, confirming the genetic uniqueness of the European local breeds compared to mainstream international breeds. The taxonomy of the local breeds revealed a cluster of the Iberian type breeds, in contrast with a wider dispersal of the breeds from other countries. Phylogeny often disagreed with documented breeds’ history, showing the complex migration/admixture patterns which underlie the breeds’ relationships. Methodologies developed in this investigation as well as the database and the DNA depository created should provide support for further innovative research in the field of domestic animal diversity management.

The genetic variations of the 5′-upstream region and the second intron of the porcine H-FABP gene were investigated by polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) in 256 pigs, including Duroc, Large White, Landrace, Neijiang, Rongchang, Bamei pig, Hanjiang Black, Hanzhong White, and wild pigs. The effect of the H-FABP gene on intramuscular fat (IMF) content was analysed by the least square method. Results showed a HinfI-RFLP in these eight pig breeds and wild pigs, among which Large White, Bamei pig, Hanjiang Black, Hanzhong White and wild pigs presented low polymorphism, while the other breeds had intermediate polymorphism. There were no HaeIII or MspI-RFLPs in the four Chinese local pig breeds tested, but Duroc, Landrace, Large White, Hanzhong White and wild pig displayed polymorphism. Landrace, Large White and wild pigs had low levels of HaeIII- and MspI-RFLP, while the others had intermediate polymorphism. H-FABP genotypes significantly affected IMF content (P<0.05). IMF content according to H-FABP genotypes were HH>Hh>hh, DD<Dd<dd, AA<Aa<aa. The genetic effect values were 3.95 (HH), 3.48 (Hh), 3.23 (hh), 2.33 (DD), 2.55 (Dd), 2.97 (dd), 2.34 (AA), 2.76 (Aa) and 3.01 (aa). Results suggest that porcine meat quality may be improved by increasing the frequency of genotype aa-dd-HH in pig breeds.

The main animal feed sources in Vietnam are rice bran, rice straw, sweet potato, sugar cane, garden by-product and natural grasses. The majority of the rural population are considered to be farmers, 75% of them practice animal husbandry of which 95% includes animal production with local breeds or crosses. Local breeds or crosses produce 80% of meat and 75% of eggs. Animal production accounts for 20–25% of the total agricultural production. Pork represents 70% of domestic meat consumption.

Low external inputs are associated with the use of natural resources. Such types of natural resources as local breeds of animal are highly respected and used in a sustainable way. Uriu cattle survived the mechanisation in rice production due to the fact that the rice fields of Nghe An are full of rocks. Dong Tao chicken keeping is increasing thanks to the gourmet tastes of exigent Vietnamese consumers. Bau Qui ducks were maintained by Vietnamese of Thai ethnic tradition who killed all animals different from their breeds coming from other parts of the Quy Chau mountains, while the I pig faced the risk of extinction due to the priority given to imported pig breeds for intensive production. The tenacious and strongly built Mong Cai pig is a feature of households in semi-intensive production.

Digestibility and nitrogen (N) balance studies were carried out on the leaves of short-term (ST) and long-term (LT) varieties of cassava, preserved by sun-drying and grinding into a meal or by ensiling. The cassava leaf meal and ensiled leaves (471 and 373 g/kg total diet dry matter, respectively) were mixed with palm syrup and palm oil, to give the experimental diets CLM and CLS, respectively. Four Mong Cai (MC) (17·2 (s.e. 2·61) kg) and four Landrace × Yorkshire (L×Y) (41·5 (s.e. 2·12) kg) male castrate pigs were used. The experiment was designed as a 2 × 2 × 2 factorial, with breed, cassava variety and processing method as factors.

The hydrogen cyanide (HCN) levels of the fresh cassava leaves of ST (545 mg/kg dry matter (DM)) and LT (408 mg/kg DM) varieties were reduced by proportionately 0·63 and 0·33, respectively, after sun-drying and by 0·78 and 0·77, respectively, after ensiling. Intake was higher for DM, crude protein (CP) and organic matter (OM) (P < 0·001) and neutral- and aciddetergent fibre (NDF and ADF) and crude fibre (CF) (P <0·01) in CLM than in CLS. There was a breed by processing method interaction for CF intake (P < 0·05). The coefficient of total tract apparent digestibility (CTTAD) was higher in CLS than in CLM for DM, CP, OM and CF (P < 0·001) and NDF and ADF (P < 0·01). The MC pigs digested ADF (P < 0·01) and CF (P < 0·001) more effectively than L×Y pigs but there was no difference (P > 0·05) in the digestibility of other nutrients or DM. There was a breed by cassava variety interaction for ADF digestibility and breed by processing method for CF digestibility (P < 0·01). Daily N intake and faecal N were higher (P < 0·001) in CLM than in CLS. Urinary N was lower in CLS than in CLM (P < 0·05) and in L×Y than in MC pigs (P < 0·001). N utilization (N retained per unit intake) was higher for CLS than CLM (P < 0·001) and in L×Y than in MC pigs (P < 0·001). It is concluded that ensiling is a more effective method than sun-drying for reducing HCN in cassava leaves after 60 days re-growth, and also results in higher digestibility of DM and dietary components than sun-drying. However, the bulkiness of the silage limits intake. The MC pigs digested dietary fibre more efficiently than the L×Y pigs, whereas the L×Y pigs utilized N more efficiently than the MC pigs.

Modern pig breeds in Europe owe their origin to a mixture of Asian and European breeds and types. They evolved during the past two hundred years, and developed particular breed characteristics by the application of breed standards, which included specific reference to colour. DNA markers at two coat colour loci provide the potential for accurate breed assignation for wild boar, Berkshire and Tamworth breeds, and may also offer the potential to develop simple tools for the verification of the origin of pork products. The use of polymorphisms in genes determining coat colour is used to explore this potential in terms of breed identification for conservation of animal genetic resources, and product traceability for quality assurance.

The Majorcan Black Pig is the only autochthonous pig breed from the island of Majorca (Spain). It is characterised by a medium size body (160 kg), slate-grey skin colour, and concave profile of the nose, large pendulous ears and tassels on the bottom neck. It is well adapted to the low-level breeding and feeding conditions of the traditional extensive management on the island. It is the base of some traditional high quality products such as the “sobrasada”, sort of red highly seasoned sausage that can be spread over bread, for which there is a good demand in the Spanish market. The Majorcan Black Pig breed played an important social and economic role until the 1960s, which then declined with the introduction of the intensive production systems and foreign breeds. The Majorcan Black Pig Association was founded in the early 1980s by a group of private farmers to recover and conserve the breed. Recently, this association has been officially recognised and the official Majorcan Black Pig Herd Book set up. At present, there are more than 600 animals registered.

An experiment was designed to test the prediction that two genetically-very-different kinds of pigs would retain the same amounts of protein in their bodies when given the same allowances of the same feed for the same period of time, when these allowances were limiting for both. An allowance of 33·957 kg of a feed with 12·76 MJ metabolizable energy (ME) and 189 g crude protein (N × 6·25)/kg feed was given to Large White × Landrace (LW ×) and Chinese Meishan (CM) female pigs over three different periods of time: (1) ad lib. (AL) with the time taken by individual pigs to consume the allowance being a variable, (2) over a period of 7 weeks (H) and (3) over a period of 9 weeks (L). In addition, in a fourth treatment, pigs of both breeds received the same allowance but supplemented with starch also over a period of 7 weeks (HS). The performance of the pigs on treatment AL was affected by pig breed, with CM pigs gaining protein at a slower, and lipid at a faster, rate than LW × pigs. On treatments L, H and HS the average amounts of protein retained were 2·693 and 2·655 kg for the LW × (n 15) and CM (n 15) pigs respectively (SED 0·106 kg). There was a statistical indication that the LW × pigs may have been more efficient on L, and less efficient on HS, than the CM pigs but we have been unable to propose any biological reason for such an effect, if it was in fact a real one. Thus, the efficiency with which ideal protein was utilized was close to being constant, and apparently at its maximum, for the two breeds. However, although CM pigs had the same protein gain, and the same live weights, on the same feed allowances as the LW × pigs, they gained significantly more lipid. This was attributed in part to their digesting their feed better and in part to their having a lower energy requirement for maintenance through a lower level of physical activity. Given that these two very different kinds of pigs use limiting protein with the same efficiency, it is suggested that it is safe to make the assumption in models of pig growth that the material efficiency of using limiting protein is constant across genotypes of pig.