Chinese Holstein Cattle Research Articles

Association of NOS2A gene polymorphisms with susceptibility to bovine tuberculosis in Chinese Holstein cattle.

Bovine tuberculosis (bTB) is a global zoonotic disease that has detrimental economic impacts worldwide. The NOS2A gene plays a key role in immunological control of many infectious diseases. However, research on the association between NOS2A polymorphisms and bTB infection in Holstein cattle reared on the Yunnan-Guizhou plateau of China is scarce. This study investigated a possible linkage between NOS2A polymorphisms and risk of developing bTB in Chinese Holstein cattle. The NOS2A gene was genotyped in 144 bTB-infected Holstein cows and 139 healthy controls were genotyped through nucleotide sequencing. Ten single-nucleotide polymorphisms (SNPs) were detected, six of which were associated with susceptibility/resistance patterns of bTB. Furthermore, the C/T genotypes of 671 and 2793, and T/T genotype of E22 (+15) were significantly associated with susceptibility risk; the G/A genotype of 2857, T/T genotype of E9 (+65), and C/C genotype of E9 (+114) probably increased resistance to bTB. In addition, the haplotypes of NOS2A-2 and NOS2A-9 were risk factors for bTB susceptibility, while the NOS2A-5 and NOS2A-8 haplotypes were contributing protective variants against tuberculosis. There is a significant association between variation in SNPs of NOS2A and tuberculosis susceptibility/resistance pattern. These findings suggest that substitution of genetic selection would be helpful for eradicating bTB. However, further investigation is required to study the underlying mechanism through which NOS2A polymorphisms affect bTB infection.

Identification of key Genes and Pathways Associated With Thermal Stress in Peripheral Blood Mononuclear Cells of Holstein Dairy Cattle.

The objectives of the present study were to identify key genes and biological pathways associated with thermal stress in Chinese Holstein dairy cattle. Hence, we constructed a cell-model, applied various molecular biology experimental techniques and bioinformatics analysis. A total of 55 candidate genes were screened from published literature and the IPA database to examine its regulation under cold (25°C) or heat (42°C) stress in PBMCs. We identified 29 (3 up-regulated and 26 down-regulated) and 41 (15 up-regulated and 26 down-regulated) significantly differentially expressed genes (DEGs) (fold change ≥ 1.2-fold and P < 0.05) after cold and heat stress treatments, respectively. Furthermore, bioinformatics analyses confirmed that major biological processes and pathways associated with thermal stress include protein folding and refolding, protein phosphorylation, transcription factor binding, immune effector process, negative regulation of cell proliferation, autophagy, apoptosis, protein processing in endoplasmic reticulum, estrogen signaling pathway, pathways related to cancer, PI3K- Akt signaling pathway, and MAPK signaling pathway. Based on validation at the cellular and individual levels, the mRNA expression of the HIF1A gene showed upregulation during cold stress and the EIF2A, HSPA1A, HSP90AA1, and HSF1 genes showed downregulation after heat exposure. The RT-qPCR and western blot results revealed that the HIF1A after cold stress and the EIF2A, HSPA1A, HSP90AA1, and HSF1 after heat stress had consistent trend changes at the cellular transcription and translation levels, suggesting as key genes associated with thermal stress response in Holstein dairy cattle. The cellular model established in this study with PBMCs provides a suitable platform to improve our understanding of thermal stress in dairy cattle. Moreover, this study provides an opportunity to develop simultaneously both high-yielding and thermotolerant Chinese Holstein cattle through marker-assisted selection.

Prevalence of nine genetic defects in Chinese Holstein cattle.

Worldwide use of elite sires has caused inbreeding accumulation and high frequencies of genetic defects in dairy cattle populations. In recent years, several genetic defect genes or haplotypes have been identified in Holstein cattle. A rapid and reliable microfluidic chip with Kompetitive allele‐specific PCR (KASP) assay was developed in our previous study for the detection of heterozygotes at eight genetic defect loci of bovine leukocyte adhesion deficiency (BLAD), Brachyspina syndrome (BS), complex vertebral malformation (CVM), Holstein haplotype 1 (HH1), Holstein haplotype 3 (HH3), Holstein haplotype 4 (HH4), Holstein haplotype 5 (HH5) and haplotype for cholesterol deficiency (HCD). This study aimed to extend that assay to include a newly identified genetic defect of Holstein haplotype 6 (HH6) and to estimate the frequencies of carriers for each of the nine genetic defects in six Chinese Holstein herds. Of the 1633 cows, carrier frequencies of the genetic defects were 6.92%, 5.76%, 4.46%, 4.30%, 3.62%, 2.94%, 1.86% and 0.37% for HH1, HH3, CVM, HH5, HCD, BS, HH6 and BLAD, respectively. No carrier was found for HH4. Notably, 27.43% of cows carried at least one genetic defect, while 2.27% and 0.12% of cows carried double and triple genetic defect alleles, respectively. The existence of genetic defects calls for routine molecular testing and effective management of genetic defects by avoiding carrier‐to‐carrier mating in production herds and eliminating or at least reducing the frequency of the defective alleles through marker‐assisted selection in breeding herds.

Single nucleotide polymorphisms in HSP70–1 gene associated with cellular heat tolerance in Chinese Holstein cows

Polymorphisms in the 5′ regulatory and translated regions of a heat shock protein 70 kDa protein –A1 (HSP70A1A) are observed as the responsible for cellular protection against heat stress and associated with heat tolerance in dairy cows. The present study was conducted to determine the genetic variation in the inducible heat shock protein 70–1 gene and its association with heat resistance in Chinese Holstein cattle. Three single nucleotide polymorphisms (SNPs) were newly identified in 149 multiparous lactating cows, using direct sequencing. Luciferase reporter assay method was conducted and showed that GG genotype in g.-133 (mutant) increased the promoter activity than did CC (wildtype). We performed DNAStar Protean Software to detect the hydrophilicity and secondary structure of the HSP70–1 protein. The results revealed the SNP in the coding region (g. 462 G/T) was found to bring changes to the amino acid sequence at 154 Gln → His. These results suggested that the genetic polymorphisms in the HSP70–1 gene may influence the heat resistance, and it can be used as a molecular marker in thermoregulation. Therefore, this study may prove beneficial of these markers in genetic selections for heat tolerance in Chinese Holstein.

Evaluation of single nucleotide polymorphisms identified through the use of SNP assay in Romanian and Chinese Holstein and Simmental cattle breeds.

Simmental and Holstein cattle, being among the most widely distributed breeds worldwide, have been subjected to continuous selection for distinct purposes. In the current study, we evaluated the levels of SNPs identified through the use of SNP assay in Romanian Holstein and Romanian Simmental cattle, which then were compared to the data from Chinese Holstein and Chinese Simmental cattle. In total, 282 animals were genotyped: Romanian Holstein (n=30), Romanian Simmental (n=22), Chinese Holstein (n=96) and Chinese Simmental cattle (n=136), using 39,724 common SNPs to analyze minor allele frequency, genetic variability and level of SNPs. Among studied breeds, the average percentage of polymorphic markers was 90.84%, with the highest value in Chinese Simmental (91.37%) and lowest in Romanian Simmental cattle (90.31%). The average HO ranged from 0.426 in Romanian Holstein to 0.416 in Romanian Simmental, and from 0.425 in Chinese Holstein to 0.422 in Chinese Simmental. The distribution of SNPs was homogenous across the breeds, except the Romanian Simmental which displayed the lowest percentage of polymorphic markers (24,66 and 32,48%) from higher MAF category (0.3 to <0.4 and 0.4 to <0.5) and the highest percentage (3.82 and 12.00%) for SNPs from low and intermediate MAF categories (0.05 to <0.1 and 0.1 to <0.2). In the current study, the SNP assay was successfully used to analyze the level of SNP sites of Romanian cattle breeds, however, a higher number of samples and production data are needed for future applications of the results in genomic selection, genome-wide association studies and genetic diversity analysis.

Copy number variation of the USP16 gene and its association with milk traits in Chinese Holstein cattle

Copy number variations (CNVs) were similar to single nucleotide polymorphisms (SNPs) and insertion-deletion (InDel), regarded as genetic variations in many species. CNV is defined as the variable change of DNA segment length compared with the reference genome, including gains or losses from 50 bp to several mega bases. The functions of USP16 gene are diverse, such as regulating the cell cycle, DNA damage, histone H2A deubiquitination or mitotic nuclear division. To analyze the relationship between CNV of USP16 gene and milk traits in Chinese Holstein, we used qPCR to detect the individuals of Chinese Holstein (n = 180). The results showed that the effect of USP16 gene CNV on daily milk yield and fat percentage had significant difference (p < 0.05). The gain was the advantage type in daily milk yield and the loss was the advantage type in fat percentage. Therefore, CNV of USP16 gene is an important factor of milk traits in Chinese Holstein. Meanwhile, it may be used as a molecular marker for assisted selection of milk traits in Chinese Holstein, which provides a theoretical basis for the genetic improvement of cow breeds in China.

Biomass derived worm-like nitrogen-doped-carbon framework for trace determination of toxic heavy metal lead (II)

The worm-like nitrogen-doped-carbon framework (WNCF) with abundant edge-plane-like defective sites (EDSs) was synthesized by using natural wax gourd (Benincasa hispida) as the main carbon precursor and milk yielded by Chinese Holstein cattle (Holstein Friesian) as the nitrogen precursor for the first time. The Nafion-dispersed WNCF (Nafion-WNCF) was employed to design a highly sensitive electrochemical sensor for the trace determination of toxic heavy metal lead (II) (Pb2+) by the differential pulse anodic stripping voltammetry (DPASV). Some key experimental factors including calcination temperature of WNCF, pH value of the buffer solution, deposition potential, deposition time and the concentration of bismuth (Bi3+) were optimized for the stripping analysis of Pb2+. Under the optimum experimental condition, Nafion-WNCF modified bismuth film glassy carbon electrode (Nafion-WNCF/BFGCE) exhibits a wide linear range from 0.5 μg L−1 to 100 μg L−1 and a low detection limit of 0.2 μg L−1 (S/N = 3) for detecting Pb2+. Especially, Nafion-WNCF/BFGCE was successfully applied to determine Pb2+ in tap water and lake water samples. All the results suggest that the WNCF can be considered as a green and low-cost nanomaterial for the precision detection of Pb2+ in real samples.

Identification of Whole-Genome Significant Single Nucleotide Polymorphisms in Candidate Genes Associated With Serum Biochemical Traits in Chinese Holstein Cattle.

A genome-wide association study (GWAS) was conducted on 23 serum biochemical traits in Chinese Holstein cattle. The experimental population consisted of 399 cattle, each genotyped by a commercial bovine 50K SNP chip, which had 49,663 SNPs. After data cleaning, 41,092 SNPs from 361 Holstein cattle were retained for GWAS. The phenotypes were measured values of serum measurements of these animals that were taken at 11 days after parturition. Two statistical models, a fixed-effect linear regression model (FLM) and a mixed-effect linear model (MLM), were used to estimate the association effects of SNPs. Genome-wide significant and suggestive thresholds were set up to be 1.22E−06 and 2.43E−06, respectively. In the Chinese Holstein population, FLM identified 81 genome-wide significant (0.05/41,092 = 1.22E−06) SNPs associated with 11 serum traits. Among these SNPs, five SNPs (BovineHD0100005950, ARS-BFGL-NGS-115158, BovineHD1500021175, BovineHD0800028900, and BTB-00442438) were also identified by the MLM to have genome-wide suggestive effects on CHE, DBIL, and LDL. Both statistical models pinpointed two SNPs that had significant effects on the Holstein population. The SNP BovineHD0800028900 (located near the gene LOC101903458 on chromosome 8) was identified to be significantly associated with serum high- and low-density lipoprotein (HDL and LDL), whereas BovineHD1500021175 (located in 73.4Mb on chromosome 15) was an SNP significantly associated with total bilirubin and direct bilirubin (TBIL and DBIL). Further analyses are needed to identify the causal mutations affecting serum traits and to investigate the correlation of effects for loci associated with fatty liver disease in dairy cattle.

Association of UDP-galactose-4-epimerase with milk protein concentration in the Chinese Holstein population.

ObjectiveAn initial RNA-Sequencing study revealed that UDP-galactose-4-epimerase (GALE) was one of the most promising candidates for milk protein concentration in Chinese Holstein cattle. This enzyme catalyzes the interconversion of UDP-galactose and UDP-glucose, an important step in galactose catabolism. To further validate the genetic effect of GALE on milk protein traits, genetic variations were identified, and genotypes-phenotypes associations were performed.MethodsThe entire coding region and the 5′-regulatory region (5′-UTR) of GALE were re-sequenced using pooled DNA of 17 unrelated sires. Association studies for five milk production traits were performed using a mixed linear animal model with a population encompassing 1,027 Chinese Holstein cows.ResultsA total of three variants in GALE were identified, including two novel variants (g.2114 A>G and g.2037 G>A) in the 5′-UTR and one previously reported variant (g.3836 G>C) in an intron. All three single nucleotide polymorphisms (SNPs) were associated with milk yield (p<0.0001), fat yield (p = 0.0006 to <0.0001), protein yield (p = 0.0232 to <0.0001) and protein percentage (p<0.0001), while no significant associations were detected between the SNPs and fat percentage. A strong linkage disequilibrium (D’ = 0.96 to 1.00) was observed among all three SNPs, and a 5 Kb haplotype block involving three main haplotypes with GAG, AGC, and AGG was formed. The results of haplotype association analyses were consistent with the results of single locus association analysis (p<0.0001). The phenotypic variance ratio above 3.00% was observed for milk protein yield that was explained by SNP-g.3836G >C.ConclusionOverall, our findings provided new insights into the polymorphic variations in bovine GALE gene and their associations with milk protein concentration. The data indicate their potential uses for marker-assisted breeding or genetic selection schemes.

SERPINA1 gene identified in RNA-Seq showed strong association with milk protein concentration in Chinese Holstein cows.

The detection of candidate genes and mutations associated with phenotypic traits is important for livestock animals. A previous RNA-Seq study revealed that SERPINA1 gene was a functional candidate that may affect milk protein concentration in dairy cows. To further confirm the genetic effect of SERPINA1 on milk protein traits, genetic polymorphisms were identified and genotype-phenotype associations were performed in a large Chinese Holstein cattle population. The entire coding region and the 5′-regulatory region (5′-UTR) of SERPINA1 was sequenced using pooled DNA of 17 unrelated sires. Association studies for five milk production traits were performed using a mixed model with a population encompassing 1,027 Chinese Holstein cows. A total of four SNPs were identified in SERPINA1, among which rs210222822 and rs41257068 presented in exons, rs207601878 presented in an intron, and rs208607693 was in the 5′-UTR. Analyses of pairwise D′ measures of linkage disequilibrium (LD) showed strong linkage among these four SNPs (D′ = 0.99–1.00), and a 9 Kb haplotype block involving three main haplotypes with GTGT, CCCC and CCGT was inferred. An association study revealed that all four single SNPs and their haplotypes had significant genetic effects on milk protein percentage, milk protein yield and milk yield (P = 0.0458 − < 0.0001). The phenotypic variance ratio for all 11 significant SNP-trait pairs ranged from 1.01% to 7.54%. The candidate gene of SERPINA1 revealed by our previous RNA-Seq study was confirmed to have pronounced effect on milk protein traits on a genome level. Two SNPs (rs208607693 and rs210222822) presented phenotypic variances of approximately 7% and may be used as key or potential markers to assist selection for new lines of cows with high protein concentration.

Genome-wide association studies for the concentrations of insulin, triiodothyronine, and thyroxine in Chinese Holstein cattle.

To further understand the genetic structure that is associated with insulin (INS) and thyroid hormones (TH), including triiodothyronine (T3) and thyroxine (T4), in Chinese Holstein cows, we conducted a genome-wide association study (GWAS) of thyroid hormones and insulin in cows. We conducted GWAS analysis on 1217 Chinese Holstein cows raised in southern China and found 19 significant single nucleotide polymorphisms (SNPs) in this study: 10 SNPs were associated with INS, 5 SNPs were associated with T3, and 4 SNPs were associated with T4. In our study, the GWAS method was used for preliminary screening on related genes of traits, and due to insufficient relevant literature, a functional analysis of genes could only be based on human studies. We observed that DGKB from Bos taurus chromosome (BTA)4 is strongly associated with insulin secretion. We found that EXOC4 gene was significantly correlated with T3 and T4 traits. Another significant SNP was located in the CYP7A1 gene, which has been confirmed to be affected by thyroid hormones.

Technical note: Development and application of KASP assays for rapid screening of 8 genetic defects in Holstein cattle

Specific DNA mutations underlying several genetic defects associated with embryo loss or reduced calf survivability have been identified in dairy cattle, and a convenient and cost-effective platform is required for their routine screening. We developed Kompetitive allele-specific PCR (KASP) assays for discrimination of the wild-type alleles from the associated defective alleles at each of 8 common genetic defects in Holstein cattle, involving 5 SNP [HH1, HH3, HH4, bovine leukocyte adhesion deficiency (BLAD), and complex vertebral malformation (CVM)] and 3 insertion or deletion mutations [HH5, haplotype for cholesterol deficiency (HCD), and brachyspina (BS)]. A total of 390 cows from a Chinese Holstein herd were genotyped and the carriers identified at 7 of these 8 loci (except HH4), with the highest carrier frequencies found for CVM (10.5%) and HH1 (10.0%), followed by HH3 (2.6%), BS (2.1%), HCD (1.3%), HH5 (0.8%), and BLAD (0.5%). Surprisingly, 102 cows (26.2%) carried at least 1 of the 7 defective alleles. Our results demonstrate that these KASP assays are simple, rapid, and reliable for the detection of multiple genetic defects. The high carrier frequency of these genetic defects indicates an urgent need for routine molecular testing to eliminate the deleterious alleles from Chinese Holstein cattle.

Identification of whole-genome significant single nucleotide polymorphisms in candidate genes associated with body conformation traits in Chinese Holstein cattle.

Identification of whole-genome significant single nucleotide polymorphisms in candidate genes associated with body conformation traits in Chinese Holstein cattle.

Mortality-Culling Rates of Dairy Calves and Replacement Heifers and Its Risk Factors in Holstein Cattle.

Simple SummaryHigh mortality and involuntary culling rates cause great economic losses to the dairy industry around the world, and the survival of dairy calves and replacement heifers is paramount in modern dairy breeding. However, little has been done to genetically improve mortality rates of dairy calves and replacement heifers in Chinese Holstein cattle. In this study, we investigated population parameters (descriptive statistics) of mortality rates of dairy calves and replacement heifers and risk factors affecting mortality and involuntary culling rates in Chinese Holstein cattle. The mortality rate of dairy calves and replacement heifers from day 3 to 60, 61 to 365, and 366 to first calving was 5.5%, 7.4%, and 8.7%, and an unfavorable increasing trend has been observed in the Chinese Holstein population. Health events associated with digestive and respiratory or circulatory systems were the main reasons for deaths. Herd-birth year, birth season, and dam parity had significant effects on survival. Our findings will help farmers to better manage dairy calves and replacement heifers and highlight the need to include these survival traits as part of the national genetic evaluation schemes.The rates of mortality and involuntary culling of dairy calves and replacement heifers have great economic implications on the dairy cattle industry around the world. The main objectives of this study were: (1) to obtain population parameters of mortality and involuntary culling rates of dairy calves and replacement heifers; and, (2) to investigate the factors affecting mortality and involuntary culling rates in Chinese Holstein cattle. Two datasets containing records of birth, calving, and culling events from 142,833 Holstein cattle born between 1991 and 2018 were used in this study. The population parameters were obtained using dataset 1, which consisted of dairy calves and replacement heifers that died or were involuntarily culled. Three survival traits were defined in dataset 2, which consisted of females born from 1999 to 2018. A binomial logistic regression was used to analyze the risk factors on the survival traits. The mortality rate of dairy calves and replacement heifers from day 3 to 60, 61 to 365, and 366 to first calving was 5.5%, 7.4%, and 8.7%, and an unfavorable increasing trend was observed. Health events associated with digestive and respiratory or circulatory systems were the main death reasons. Herd-birth year, birth season, and dam parity had significant effects on survival traits. The results from this study will help farmers to better manage calves and replacement heifers and highlight the need to include survival traits in dairy calves and replacement heifers as part of national genetic evaluation schemes.

Genome-wide association study identifies loci linked to serum electrolyte traits in Chinese Holstein cattle.

We aimed to identify QTL for serum electrolyte traits by performing a GWAS of calcium, chloride, sodium, potassium and magnesium ion concentrations in Chinese Holstein cattle. We detected five SNPs that had significant associations with calcium ion concentrations and identified GATA2 from Bos taurus chromosome (BTA)22 as having the highest significance. Among the genes with significant results, we speculate that TMEM123 might be related to calcium channel proteins according to the functions of the TMEM family.

Identification of genetic markers associated with milk production traits in Chinese Holstein cattle based on post genome-wide association studies

With the rapid development of dairy industry, the breeding process of dairy cows has been accelerated. In previous genome-wide association studies (GWAS), a large number of genetic markers have been reported which may contribute to the selection of Holstein populations with superior milk-producing traits, but they remain to be further verified before practical application. In this study, 90 single nucleotide polymorphisms (SNPs) were selected, which were reported to be significantly associated with five milk production traits, including 305-day milk yield (305MY), 305-day milk fat percent (305FC), 305-day milk protein percent (305PC), 305-day milk fat yield (305FY) and 305-day milk protein yield (305PY). Effective 305-day data and fresh DNA samples were obtained from 295 healthy cows with gestational age of 1–4. Matrix-assisted laser desorption/ionization—time of flight (MALDI-TOF) was used to perform precise genotyping of these loci, followed by site association and haplotype analysis. Results showed that 36 out of 90 loci were supported to be used as genetic markers. In particular, several novel and effective haplotypes were also presented. Overall, our results verified tens of useful markers and provided a basis for further development of breeding strategies.

Genome-wide association study identifies energy metabolism genes for resistance to ketosis in Chinese Holstein cattle.

Ketosis (KET) is one common metabolic disorder that occurs mainly in early lactation and affects the dairy industry with significant economic losses. Cows with ketosis have lower milk yield and reproductive performance and greater risk of other periparturient diseases. As a metabolic disease, the pathogenesis of KET is multifactorial. To better understand the genetic background of KET, a genome-wide association study was performed using the Illumina BovineSNP50 BeadChip. Single-step genomic BLUP methodology was used to incorporate genomic data into a threshold-liability model. Results of the GWAS are reported as the proportion of variance explained by 20-SNP windows. Six genomic regions on Bos taurus autosomes 10, 13, 14 and 25 showed association with KET. Most interestingly, several candidate genes, including previously reported genes (BMP4, HNF4A and APOBR) and newly identified genes (SOCS4, GCH1, ATG14, RGS6, CYP7A1 and MAPK3), are involved in insulin metabolism or lipid metabolism, implicating the contribution of energy-metabolism-associated genes to the genetic basis of KET. Our results provide new information about the underlying biology and molecular mechanisms associated with KET. Future studies that combine genomic variation analysis and functional gene information may help elucidate the biology of KET.

The cholesterol-deficiency associated mutation in APOB segregates at low frequency in Chinese Holstein cattle

Cholesterol deficiency (CD) is a recessive genetic defect in Holstein cattle, which affects the rearing success of calves. We investigated whether CD has been spread into the People’s Republic of China. A total of 138 Holstein bulls and 90 cows were screened for CD using polymerase chain reaction amplification and then seven bulls (5.07%) and one cow (1.11%) were identified as CD carriers. Pedigree analyses revealed that all seven CD carrier bulls were traced back to MAUGHLIN STORM and CD may have spread into the People’s Republic of China through his daughter, Braedale Baler Twine. Our results demonstrated that the CD defect exists in the Chinese Holstein population.

Change in Chemical Composition of Simmental Crossbred Cattle Milk Improved its Physicochemical, Nutritional, and Processed Properties.

This study aimed to evaluate a new milk resource from Simmental crossbred cattle, which could be an alternative raw milk for dairy products. In the experiment, physicochemical characterization of raw milk was evaluated according to the Standards. In addition, Simmental crossbred cattle milk (SHCM) samples had the higher contents of total amino acid than those of Chinese Holstein cow milk (HCM) samples, especially for Leu, Lys, Met, and Phe. We also observed the contents of protein, fat, and lactose in SHCM samples changed during 12 months, where in milk fat content was mostly affected by the season, followed by the lactose and protein contents. Moreover, texture profile analysis showed that yoghurt made from SHCM had stronger structures, which especially reflected in hardness and chewiness. The G' of yoghurt made from SHCM during storage time was always higher than that made from HCM, indicating that SHCM yoghurt showed higher apparent viscosity values. Logically, the milk from Simmental crossbred cattle has desirable physicochemical characteristics and nutritional value, which could be a new better resource of dairy products. PRACTICAL APPLICATION: Compared with Chinese Holstein cattle, Simmental crossbred cattle have strong resistance to moist weather and better performance in disease resistance, which are particularly important for lactating cows persisting in south of China. We evaluated the nutritional values of SHCM and HCM, and compared the seasonal variation on chemical composition of SHCM sample. All the data could be used to produce different dairy products using raw milk from different seasons. In addition, textural properties of yoghurt made from two milks were also determined, and we suggested that SHCM could be used as a new resource candidate for developing dairy product in the future.

Polymorphisms of mannose-binding lectin-associated serine protease 1 (MASP1) and its relationship with milk performance traits and complement activity in Chinese Holstein cattle

ObjectiveMannose-binding lectin (MBL)-associated serine protease1 (MASP1) is the central enzyme in the innate immune system, which has biological functions of antibacterial and anti-inflammatory activities. Moreover, MASP1 represents a candidate gene reflecting the complement activity. This study is to investigate the entire exons of MASP1 in Chinese Holstein cattle with DNA sequencing to identify novel single nucleotide polymorphisms (SNPs). MethodsNovel SNPs were identified through gene sequencing and genotyped by the PCR Restriction Fragment Length Polymorphism (PCR-RFLP) and Created Restriction Site PCR (CRS-PCR). The relationship between the milk performance traits and complement activity in Chinese Holstein cattle was analyzed using the General Linear Model (GLM) procedure with the SAS software (version 8.0). ResultsTwo novel SNPs (i.e., g.5766A > G and g.51228A > C) were detected. The SNP g.5766A > G was located in the first intron and the SNP g.51228A > C was located in the 3′-untranslated regions of MASP1. The polymorphism at g.5766A > G was correlated with protein percentage (P < 0.05). Moreover, the polymorphism at g.51228A > C had only two genotypes, and this SNP had no significant correlation with CH50, ACH50, fat percentage, protein percentage, 305-day milk yields, or SCS scores. ConclusionMASP1, reflecting the complement activity, may not be significantly related to mastitis. However, MASP1 could be implemented in the breeding program to improve the production performance of Chinese Holstein cattle.