Reproductive performance of indigenous Lao pigs reared by small-scale farmers in northern provinces of Laos

Indigenous pigs are essential domestic animals for rural life and meat supply in Laos, especially for ethnic people in remote areas. Northern provinces have the most numerous indigenous pig populations, i.e. covering 84 % of the total pig population. This study was conducted in northern Laos, where 164 pig-raising households, 325 sows and 1246 piglets were included. The study aimed to observe the general trend of change in indigenous pig utilization and the altered reproductive performance regarding village location and rearing systems. The semi-structured questionnaires were a key tool for gathering data required through personal interviews and field observations. Two types of indigenous Lao pig breeds (locally named Moo Lath and Moo Hmong) were found in study areas. The village locations were not influencing on reproductive performance of indigenous Lao pigs. Larger litter size and birth weight (P<0.004–0.000) was found in the second cluster (15 to 30 km away from downtown) with an average of 8.24 heads and 0.88 kg, while the first (<15 km) and third (>30 km) clusters had 7.72 versus 7.12 heads, and 0.70 versus 0.63 kg, respectively. Conversely, the second cluster had lower litter per year (P<0.001) by 1.04, compared to 1.38 for the first and third clusters. The free-scavenging rearing system (FRS) had a higher litter size (8.5) than the confinement (CRS) and semi-scavenge (SRS) rearing system (7.36 versus 7.54). The FRS had a marginally smaller litter per year (0.87) that differed from the CRS and SRS (1.45 and 1.41). The CRS had a shorter suckling period (2.38 months) with a lower weaning weight (6.74 kg), while the FRS and SRS had longer (2.72 versus 2.8 months) and higher weaning weight (7.76 and 7.57 kg). The mortality before weaning was 15 %, and no difference was found related to the villages' location or rearing systems (P>0.070 versus 0.839). Around 56 % of the piglet's deaths were due to poor management that caused piglets to be crushed/injured by sow or starvation. More than 54 % of farmers did not keep sows in pens before the farrowing, and 53 % of sows gave birth near forests. In conclusion, the village locations and rearing systems did not influence the reproductive performance of indigenous pigs in northern Laos. However, pre- and post-farrowing management had a strong effect on it. During the whole study, we took into consideration the successful example of Hungarian Mangalica pig, which could find a proper new role in the global premium markets. Our results suggest that similar complex semi-intensive farm operations as indigenous Mangalica pig farms in Hungary should be a great option for introducing and adapting to improve indigenous pig performance in Laos.

Genomic Analysis Reveals Human-Mediated Introgression From European Commercial Pigs to Henan Indigenous Pigs

Introgression of genetic features from European pigs into Chinese pigs was reported possibly contributing to improvements in productivity traits, such as feed conversion efficiency and body size. However, the genomic differences from European pigs and the potential role of introgression in Henan indigenous pigs remains unclear. In this study, we found significant introgression from European pigs into the genome of Chinese indigenous pigs, especially in Henan indigenous pigs. The introgression in Henan indigenous pigs, particularly in the Nanyang black pig, was mainly derived from Duroc pigs. Most importantly, we found that the NR6A1, GPD2, and CSRNP3 genes were introgressed and reshaped by artificial selection, and these may have contributed to increases in pig body size and feed conversion efficiency. Our results suggest that human-mediated introgression and selection have reshaped the genome of Henan pigs and improved several of their desired traits. These findings contribute to our understanding of the history of Henan indigenous pigs and provide insights into the genetic mechanisms affecting economically important traits in pig populations.

Whole-Genome Resequencing Reveals Genetic Structure and Introgression in Chinese Pudong White Pigs

Background: Pudong white (PDW) pigs originating from Shanghai, are the only Chinese indigenous pigs with white coat color except Rongchang (RC) pigs. However, there is limited information about its overall genetic structure, relationship with other breeds especially the East Chinese (ECN) and European pig due to the white coat of PDW. Whole-genome sequencing provides the effective approach to get the unique information of genome. The high-depth whole-genome sequencing data of 26 global pig breeds, European Wild boars (EWB), Chinese Wild boars (CWB) and out group (OUT) were implemented to detect the genetic structure, signature of selection and potential exotic introgression in PDW pigs.Results: The PDW pigs belonging to ECN pigs based on genetic relationship, and harbor lower genetic diversity and higher inbreeding coefficient compared to other Chinese indigenous pigs. Both the f3 and D-statistics analysis demonstrated that PDW pigs shared apparent alleles with Large White (LW) pigs. Then, two statistics, haplotype heat-map, copy number variation (CNV) and rIBD analysis further revealed that PDW pigs carry the same KIT genotype and share haplotypes at PARG-MARCHF8 locus with LW pigs, suggesting that the lineage of European (EUR) pigs in PDW originated from LW pigs. After detecting the KIT mutations in different pig breeds, PDW was confirmed to be same with LW at DUP1, DUP2 and the splicing mutation on intron 17 of KIT which determine the white coat color phenotype in European white pigs.Conclusions: This study shows that ECN pigs crossed with LW pigs after introduced to China about 110-164 years ago, where the offspring carrying KIT genotype that caused white coat color phenotype, and then were selected due to the rare white coat color in Chinese indigenous pigs, gradually forming PDW pig breed. To our knowledge, this study gives the first thorough description of the genetic structure of PDW pig via whole-genome resequencing data. This study not only advances our understanding of genetic structure, molecular phylogeny, and molecular origin of PDW pigs, but also provides a basis for facilitating the development of a national project for the conservation and utilization of this unique Chinese local population.

Performance of the Indigenous Pigs of Nigeria Under Intensive Management Conditions

OBSERVATIONS on some reproductive traits were made on 63 litters of indigenous pigs obtained from pigs selected from an initial group of 60 pigs purchased from local farmers around Ibadan between April 1972 and February 1976. Studies on the growth rate, feed intake and feed efficiency, as well as the proportion of separable tissue in carcass at different terminal weights, rate and efficiency of tissue growth were also carried out with a total of 394 pigs obtained from these litters. For the observations on performance, tissue proportions, tissue growth rate and efficiency of tissue deposition, Large White x Landrace pigs of the same age group were used for comparison at each stage. Litter size averaged 6.7 piglets per sow with a range value of between 4 and 13 piglets. Mean litter birth weight was 6.10 kg, while mean litter weaning weight was 29.4 kg. A preweaning mortality of 15.8% and 4.79% still births were recorded for these indigenous pigs. Daily gain, feed intake and feed conversion efficiency were lower for the indigenous compared to Large White X Landrace pigs. Maximum growth rate for these pigs occured in the growth phase between 45.5 and 56.8 kg. liveweights. Tissue growth rates were lower and the efficiency of tissue deposition poorer in the indigenous compared to the Large White x Landrace pigs. The basic factor underlying the differences in performance of these two breeds would appear to be the inherently different patterns of growth of the respective tissue. The rate and efficiency of tissue growth as well as growth and efficiency of feed utilisation, together indicate that the indigenous pigs should not be reared beyond liveweights between 45.5 and 56.8 kg.

Prediction Of Carcass Lean Content In Live Pigs Using Scanoprobe Ultrasonic Machine

A total of 40 entire males within 60kg weight range from Large White control and selected crossbred improved indigenous pigs were used to study relationships between live and carcass measurements using the Scanoprobe ultrasonic machine. Within this live weight range the fat depths (P1, P2 and P3)and muscle measurements (MP2 and MLA) were more variable in the crossbreds than the purebred exotics although the carcass lean content, 365g/kg and 395g/kg for the purebred and crossbreds respectively were not significantly different. The fat depths, using the ultrasonic machine was a little lower than the actual values: 15.1 as against 16.6mm for P1 and 15.05 against 16.3mm for P2 with a residual standard deviation of 2.56 and 3.25mm respectively. Whilst the MLA gave values of 2886mm2 for ultrasonics as against 3025mm2 for carcass measurement with S.D. of 357 and 328mm2 respectively. Relative to the different fat depths measurements, the regression of carcass lean on P1 was -3.90±1.716 whilst at P2 and P3 it was -2.94±0.949 and -3.41±0.810gms respectively, resulting in a prediction equation for lean content of 57.85 - 0.751 P2 gm.

Comparative Physical Characteristics in the Indigenous Nigerian and Imported European Pigs

THE Physical carcass characteristics of 100 indigenous Nigerian pigs (IND.) (50 gilts and 50 barrows), and 100 Large White x Landrace pigs with a similar sex ratio were compared. These were slaughtered at either one of five weights, 22.7, 34.0, 45.5, 56.8 or 68 kg live weight, in such a way that 10 gilts and 10 barrows of each breed were slaughtered at each of the predetermined slaughter weights. For the purpose of comparing sexual influences on physical carcass traits in the indigenous pigs carcass data were obtained on an additional group of 50 indigenous boars during the same period as the above it similar Slaughter weights involving similar numbers per slaughter weight. In a third experiment carcass data were collected on 40 pure Large White pigs (LW) (20 gilts and 20 barroWs) and 40 indigenous x Large White pigs (IND.XLW) also made up of 20 gilts and 20 barrows. A comparison was made between these and the data on a similar number of indigenous barrows and gilts. The results indicated highly significantly different (P <0.01). Proportions of lean and fat and significantly (P <0.05) different proportions of bone and skin in the carcasses of IND and LWXLD pig. The LWXLD pigs had more lean, and bone, less fat and skin, than the indigenous pigs. Carcass conformation was also clearly different in both breeds. The indigenous pigs had lower proportion of lean cuts and greater proportion of the fat cuts than the LWXLD pigs at all Slaughter weights. From 22.7 to 68 kg slaughter weights, the IND pigs were shorter, had thicker backfat, higher dressing percentage and smaller loin eye muscle area compared to the LWXLD pigs. Percentages lean, bone skin, ham, loin, shoulder and sum of four lean cuts decreased while percentages fat, fat cuts, trimmed fat and backfat thickness increased with increasing slaughter weights for both breeds. A comparison of carcass traits in the indigenous boars, barrows and gilts showed that the boars were leaner and had superior carcass conformation to the gilts which in turn were leaner than barrows. Crosses between the indigenous pigs and pure large White pigs were superior to the pure indigenous pigs in terms of carcass length, greater proportion of lean to fat and thinner backfat measurements, while they were inferior to the Pure Large White pigs in terms of these measurements.

CORRELATED RESPONSES IN WEIGHTS OF IMPROVED INDIGENOUS PIGS - NIGERHYB - IN NIGERIA

Data collected on the weight of 1681 offsprings of improved indigenous pigs from 1984 to 1990 were used to obtain heritability estimates; genetic, environmental and phenotypic correlations among weights and gains from birth to mature and yearling weights. The estimates were used to predict expected change from correlated responses from single trait selection. Heritability estimates obtained from paternal half-sib analysis were birth weight 0.90 ±0. 08; gain from birth to weaning 0.14±0.11; 150 days weight 0.49±18; gain from weaning to 150 days 0.49±0.15; weight gain from.150 days to yearling weight 0.41 ± 026 and yearling weight 0.66±. Genetic correlations among all weights and gains were fairly high, ranging from 0.25 to 0.81. Selection for individual pig weight at 56 days appear to be a single good criterion for selection for growth at other ages with coheritabilities of 0.669 for 56 and 150 days weight and 0,856 for 56 days versus yearling weight.