家猪(Sus scrofa domestica)体细胞染色体的研究

家猪体细胞染色体(2n=38)已有报道。近年来应用染色体分带技术对家猪染色体作了进一步鉴定。但由于方法不同和缺乏统一标准,其结果不完全一致。对于我国家猪品种染色体的研究,目前尚少报道。我们以四川的内江猪、荣昌猪、柳加猪和成华猪为对象,用外周血淋巴细胞培养方法制备染色体,用Giemsa常规染色,G-分带和C-分带染色,对这些家猪的染色体组型,G-分带和C-分带作了详细的分析。

Environmental drivers of seasonal shifts in abundance of wild pigs(Sus scrofa)in a tropical island environment

Background:Non-native wild pigs(Sus scrofa)threaten sensitive flora and fauna,cost billions of dollars in economic damage,and pose a significant human–wildlife conflict risk.Despite growing interest in wild pig research,basic life history information is often lacking throughout their introduced range and particularly in tropical environments.Similar to other large terrestrial mammals,pigs possess the ability to shift their range based on local climatic conditions or resource availability,further complicating management decisions.The objectives of this study were to(i)model the distribution and abundance of wild pigs across two seasons within a single calendar year;(ii)determine the most important environmental variables driving changes in pig distribution and abundance;and(iii)highlight key differences between seasonal models and their potential management implications.These study objectives were achieved using zero-inflated models constructed from abundance data obtained from extensive field surveys and remotely sensed environmental variables.Results:Our models demonstrate a considerable change in distribution and abundance of wild pigs throughout a single calendar year.Rainfall and vegetation height were among the most influential variables for pig distribution during the spring,and distance to adjacent forest and vegetation density were among the most significant for the fall.Further,our seasonal models show that areas of high conservation value may be more vulnerable to threats from wild pigs at certain times throughout the year,which was not captured by more traditional modeling approaches using aggregated data.Conclusions:Our results suggest that(i)wild pigs can considerably shift their range throughout the calendar year,even in tropical environments;(ii)pigs prefer dense forested areas in the presence of either hunting pressure or an abundance of frugivorous plants,but may shift to adjacent areas in the absence of either of these conditions;and(iii)seasonal models provide valuable biological information that would otherwise be missed by common modeling approaches that use aggregated data over many years.These findings highlight the importance of considering biologically relevant time scales that provide key information to better inform management strategies,particularly for species whose ranges include both temperate and tropical environments and thrive in both large continental and small island ecosystems.

Molecular characterization of thyroid peroxidase gene in porcine (sus scrofa)

Thyroid peroxidase （TPO） is the key enzyme involved in thyroid hormone synthesis. Several mutations in the TPO gene may affect the normal growth and development of mammals. In this study, the TPO gene was mapped, its expression level was determined in thyroid grand at the age of 1, 20, 45, 60, 90, 120 and 150 days for Jinhua pig, the alternative splicing form was searched and the single nucleotide polymorphism （SNP, A/G642） of TPO gene was analyzed. The results showed that the porcine TPO was mapped to 3q22-27, the expres- sion level of TPO was relatively stable among the various ages and two novel transcript variants in porcine TPO gene were found： the splicing variant TPO-2 lacked exon 8, while TPO-3 lacked exon 8 and exon 14, 15, 16. Moreover, we found that the SNP of A/G642in the fourteenth exon of TPO gene was significantly associated with ham weight （P 〈 0.05）. Our results provided important basis on the regulation and metabolism of the thyroid gland in animals.

太行山东北部区域野生动物损害及损害补偿

人兽冲突是生物多样性保护的重要研究主题,合理的损害补偿有助于野生动物可持续保护及管理。为探究太行山东北部区域野生动物损害及损害补偿,于2019年与2020年7—9月对区域内主要肇事野生动物(野猪Sus scrofa和狗獾Meles leucurus)进行了种群及损害调查;2021年7—8月基于访谈,对区域的损害赔偿及社区的受偿意愿进行了量化计测和分析。结果表明,太行山东北部区域的野猪(密度为(6.283±1.274)只/km^(2))及狗獾(密度为(4.855±1.610)只/km^(2))种群较大,对区域内的农业生产带来了较大损害,且肇事频率呈上升趋势;已有的防控手段效果有限,当地社区对野生动物保护支持度较高,但对肇事动物保护的态度相对消极;区域内的野生动物损害补偿已普遍施行,有效补偿了受损农户的部分经济损失,但也存在补偿覆盖不全面、补偿标准模糊及补偿数额偏低等问题。当地农户的受偿意愿((10962.60±1751.55)元/hm^(2))与其文化程度、损害补偿满意度和野生动物保护态度负相关,与保护政策支持度正相关。根据调研结果,建议加大力度落实野生动物损害补偿政策、构建野生动物损害保险制度、开展长期监测,并控制野生动物种群数量,最终通过调整土地利用模式、提供替代生计等方法,化解人兽冲突矛盾。

Estimation of inbreeding and identification of regions under heavy selection based on runs of homozygosity in a Large White pig population

Background: Runs of homozygosity(ROHs) are homozygous segments of the genome where the two haplotypes inherited from the parents are identical. The current availability of genotypes for a very large number of single nucleotide polymorphisms(SNPs) is leading to more accurate characterization of ROHs in the whole genome. Here,we investigated the occurrence and distribution of ROHs in 3,692 Large White pigs and compared estimates of inbreeding coefficients calculated based on ROHs(FROH), homozygosity(FHOM), genomic relationship matrix(FGRM)and pedigree(FPED). Furthermore, we identified genomic regions with high ROH frequencies and annotated their candidate genes.Results: In total, 176,182 ROHs were identified from 3,569 animals, and all individuals displayed at least one ROH longer than 1 Mb. The ROHs identified were unevenly distributed on the autosomes. The highest and lowest coverages of Sus scrofa chromosomes(SSC) by ROH were on SSC14 and SSC13, respectively. The highest pairwise correlation among the different inbreeding coefficient estimates was 0.95 between FROH_totaland FHOM, while the lowest was-0.083 between FGRMand FPED. The correlations between FPEDand FROHusing four classes of ROH lengths ranged from 0.18 to 0.37 and increased with increasing ROH length, except for ROH > 10 Mb. Twelve ROH islands were located on four chromosomes(SSC1, 4, 6 and 14). These ROH islands harboured genes associated with reproduction, muscular development, fat deposition and adaptation, such as SIRT1, MYPN, SETDB1 and PSMD4.Conclusion: FROHcan be used to accurately assess individual inbreeding levels compared to other inbreeding coefficient estimators. In the absence of pedigree records, FROHcan provide an alternative to inbreeding estimates.Our findings can be used not only to effectively increase the response to selection by appropriately managing the rate of inbreeding and minimizing the negative effects of inbreeding depression but also to help detect genomic regions with an effect on traits under selection.

Evolution and Expression Patterns of Forkhead Box N1 in Pig

The thymus is essential for T-cell development. The transcription factor Foxn1 plays an important role in the development and function of thymic epithelial cells （TECs） in vertebrates. However, the transcriptional regulation and expression pattern of Foxn1 in pig is not known. Here, the complete sequence of pig Foxn1 was sequenced. Sequence analysis showed that the pig Foxn1 gene was 14 730 bp in length. Its cDNA full coding sequence （CDS） consisted of 1 941 bp nucleotides that encoded a 646-amino acid polypeptide. Its amino acid sequence comprised a conserved forkhead 3 domain spanning amino acids 269-365. Phylogenetic reconstruction of the Foxn1 nucleotide sequence of the pig and other species revealed that the pig Foxn1 gene was closely related to the sheep and cattle Foxn1 genes. Foxn1 gene was conserved in mammals. RT-PCR analysis showed that Foxn1 was only expressed in the thymus, skin and tongue, but not in the heart, liver, spleen, lung, kidney, adrenal gland, subcutaneous fat, longissimus dorsi, large intestine, small intestine, stomach, mesenteric lymph node, throat and ovary. These fndings indicated that the expression pattern of Foxn1 was tissue-specifc.

Sex-specifc seasonal variations of wild boar distance traveled and home range size

Distance traveled and home range size describe how animals move in space.The seasonal variations of these parameters are important to comprehensively understand animal ecology and its connection with reproductive behavior and energy costs.Researchers usually estimate the distance traveled as the sum of the straight-line displacements between sampled positions,but this approach is sensitive to the sampling frequency and does not account for the tortuosity of the animal’s movements.By means of the continuous-time movement modeling which takes into account autocorrelation and tortuosity of movement data,we estimated the distance traveled and monthly home range size of 28 wild boar Sus scrofa and modeled their inter-sexual seasonal variability.Males traveled longer distances and used larger home ranges than females,particularly during the rut in autumn-winter,consistently with the different biological cycles of males and females.Males enlarged their home ranges during the rut but traveled constant average distances along the year,whereas females traveled shorter distances in correspondence with the peak of food resources and birth periods but exhibited constant home range size across seasons.The differences between the seasonal variation patterns of distance traveled and home range size,observed in both sexes,revealed the complex relationship between these two aspects of spatial behavior and the great opportunity of including both distance traveled and home range size in behavioral ecology investigations.We provided a detailed analysis of wild boar spatial behavior and its relationships with the reproductive cycles of males and females,promoting a deeper comprehension of their behavioral ecology.

Lung microRNA profile in chronic cyanotic piglets with decreased pulmonary blood flow

Background Cyanotic congenital heart defects with decreased pulmonary blood flow due to lung ischemia,hypoxia,and others lead to infant morbidity and mortality more than acyanotic heart disease does.Despite the great effort of medical research,their genetic link and underlying microRNAs molecular mechanisms remain obscure.In this study,we aimed to investigate microRNAs regulation during cyanotic defects in lung of immature piglets.Methods Cyanotic piglet model was induced by main pulmonary artery-left atrium shunt with distal pulmonary artery banding.Four weeks later,hemodynamic parameters confirmed the development of cyanotic defects and pulmonary lobe RNA was extracted from all animals.We studied the repertoire of porcine lung microRNAs by Solexa deep sequencing technology and quantified highly expressed microRNAs by microarray hybridization.Furthermore,we quantitated selected microRNAs from cyanotic and control piglets by quantitative RT-PCR.Results After surgical procedure 4 weeks later,the cyanotic model produced lower arterial oxygen tension,arterial oxygen saturation,and higher arterial carbon dioxide tension,hematocrit and hemoglobin concentration than controls （all P 〈0.05）.In 1273 miRNAs expressed in the immature piglets lungs,2 most abundant microRNAs （miR-370 and miR-320） demonstrated significant difference between cyanotic and control group （all P 〈0.05）.Conclusion Our results extended lung microRNA profile in immature piglets and suggested that miR-370 and miR-320 are significantly up-regulated in cyanotic lung tissues.

Ancient DNA reveals the maternal genetic history of East Asian domestic pigs

Zoo-archaeological and genetic evidence suggest that pigs were domesticated independently in Central China and Eastern Anatolia along with the development of agricultural communities and civilizations.However,the genetic history of domestic pigs,especially in China,has not been fully explored.In this study,we generate 42 complete mitochondrial DNA sequences from~7500-to 2750-year-old individuals from the Yellow River basin.Our results show that the maternal genetic continuity of East Asian domestic pigs dates back to at least the Early to Middle Neolithic.In contrast,the Near Eastern ancestry in European domestic pigs saw a near-complete genomic replacement by the European wild boar.The majority of East Asian domestic pigs share close haplotypes,and the most recent common ancestor of most branches dates back to less than 20,000 years before present,inferred using new substitution rates of whole mitogenomes or combined protein-coding regions.Two major population expansion events of East Asian domestic pigs coincided with changes in climate,widespread adoption of introduced crops,and the development of agrarian societies.These findings add to our understanding of the maternal genetic composition and help to complete the picture of domestic pig evolutionary history in East Asia.