Cattle In Terms Research Articles

Влияние геопровинциальных и технологических факторов на обмен минеральных веществ у лактирующих коров в условиях интенсификации производства

In cattle breeding enterprises of the Vladimir region, regardless of the intensity of production and keeping technologies, cows exhibit violations of the reproductive cycle associated with an imbalance in mineral metabolism. Highly productive cows have rather low rates of commercial offspring, and the service period exceeded the general norm for Holsteinized black-and-white cattle. At the same time, the specific gravity of soils with an insufficient content for most agricultural forage crops for cattle in terms of cobalt – 95,8%, zinc – 81,9%, manganese – 63,8%, copper – 52,9% of the total arable area land. The performed gynecological clinical examination of lactating cows using mammological examinations and taking into account the geoprovincial characteristics of the Vladimir region, makes it possible to determine the nature of the prevailing pathology, to establish its main causes, and to present specific proposals for carrying out preventive and therapeutic measures based on the real capabilities of farms.

Crossbreed Cattle: Assessment and Challenges of Breeding in Selected Districts of Tigray and Afar Regional States, Ethiopia

The practice of animal husbandry has played an important role in enhancing sustainable development and improving food security of the community. However, the contribution of this sector towards the national as well as regional economy is very small. The focus of this research is to identify the main reasons why rural farmers do not own rear crossbreed cattle. The data obtained reveals that the majority of the rural communities dont have the right knowledge about the importance of crossbreed cattle in terms of their high yield. Some of the rural residents who are aware said they have limited financial access to afford crossbreed cattle. Besides, the respondents replied that the lack of appropriate feed and its high consumption is another reason, although the output gained from crossbreed cattle is quite high compared to the indigenous animals. Therefore, with the available livestock resource in Ethiopia it is recommended to increase the awareness of importance of crossbreed cattle, and government should also focus on creating favorable conditions to access to financial resources and feed for cattle. Solving the main bottlenecks will assure sustainable development and enable to meet the growing demand of the region. In addition to this, the income disparities between farmers and other self and government employed resident can be minimized.

Diversity analysis at MHC class II DQA locus in buffalo (Bubalus bubalis) indicates extensive duplication and trans-species evolution

Variation at MHC Class II-DQA locus in riverine and swamp buffaloes (Bubu) has been explored in this study. Through sequencing of buffalo DQA, 48 nucleotide variants identified from 17 individuals, reporting 42 novel alleles, including one pseudogene. Individual animal displayed two to seven variants, suggesting the presence of more than two Bubu-DQA loci, as an evidence of extensive duplication. dN values were found to be higher than dS values at peptide binding sites, separately for riverine and swamp buffaloes, indicating locus being under positive selection. Evolutionary analysis revealed numerous trans-species polymorphism with alleles from water buffalo assigned to at least three different loci (Bubu-DQA1, DQA2, DQA3). Alleles of both the sub-species intermixed within the cluster, showing convergent evolution of MHC alleles in bovines. The results thus suggest that both riverine and swamp buffaloes share con-current arrangement of DQA region, comparable to cattle in terms of copy number and population polymorphism.

Epigenomics and genotype-phenotype association analyses reveal conserved genetic architecture of complex traits in cattle and human

BackgroundLack of comprehensive functional annotations across a wide range of tissues and cell types severely hinders the biological interpretations of phenotypic variation, adaptive evolution, and domestication in livestock. Here we used a combination of comparative epigenomics, genome-wide association study (GWAS), and selection signature analysis, to shed light on potential adaptive evolution in cattle.ResultsWe cross-mapped 8 histone marks of 1300 samples from human to cattle, covering 178 unique tissues/cell types. By uniformly analyzing 723 RNA-seq and 40 whole genome bisulfite sequencing (WGBS) datasets in cattle, we validated that cross-mapped histone marks captured tissue-specific expression and methylation, reflecting tissue-relevant biology. Through integrating cross-mapped tissue-specific histone marks with large-scale GWAS and selection signature results, we for the first time detected relevant tissues and cell types for 45 economically important traits and artificial selection in cattle. For instance, immune tissues are significantly associated with health and reproduction traits, multiple tissues for milk production and body conformation traits (reflecting their highly polygenic architecture), and thyroid for the different selection between beef and dairy cattle. Similarly, we detected relevant tissues for 58 complex traits and diseases in humans and observed that immune and fertility traits in humans significantly correlated with those in cattle in terms of relevant tissues, which facilitated the identification of causal genes for such traits. For instance, PIK3CG, a gene highly specifically expressed in mononuclear cells, was significantly associated with both age-at-menopause in human and daughter-still-birth in cattle. ICAM, a T cell-specific gene, was significantly associated with both allergic diseases in human and metritis in cattle.ConclusionCollectively, our results highlighted that comparative epigenomics in conjunction with GWAS and selection signature analyses could provide biological insights into the phenotypic variation and adaptive evolution. Cattle may serve as a model for human complex traits, by providing additional information beyond laboratory model organisms, particularly when more novel phenotypes become available in the near future.

Association between polymorphisms of Myf5, MSTN and CAST genes and fattening performance in Brown Swiss and Holstein cattle breeds

This study determined the association between Myf5, CAST and MSTN genes and fattening performance traits in 228 (Holstein = 103 and Brown = 125) cattle breeds. Classification and regression tree (CART) was used to determine association between genes and fattening performance. The allele frequencies of Holstein cattle in terms of Myf5, CAST and MSTN genes were A:0.30, B:0.70; A:0.43, G:0.56; A:0.97, B:0.03, respectively, whereas in the Brown Swiss cattle were A:0.36, B:0.64; A:0.65, G:0.34; A:0.88, B:0.12 respectively. The Myf5, CAST, and MSTN genes were found to be in the Hardy–Weinberg equilibrium (p > 0.05) in both of the cattle breeds. As a result, the association between Myf5, CAST and MSTN genes and fattening performance traits were found to be significant according to CART analysis.

Natural 15N abundance in specific amino acids indicates associations between transamination rates and residual feed intake in beef cattle.

Improving the ability of animals to convert feed resources into food for humans is needed for more sustainable livestock systems. Genetic selection for animals eating less while maintaining their performance (i.e., low residual feed intake [RFI]) appears a smart strategy but its effectiveness relies on high-throughput animal phenotyping. Here, we explored plasma nitrogen (N) isotope ratios in an attempt to identify easily superior young bulls in terms of RFI. For this, 48 Charolais young bulls fed two contrasting diets (corn vs. grass silage diets) were selected from a larger population as extreme RFI animals (24 low-RFI vs. 24 high-RFI) and their plasma analyzed for natural 15N abundance (δ15N) in the whole protein (bulk protein) and in the individual protein-bound amino acids (PbAA). For the first time, we showed that the δ 15N in plasma bulk protein differed (P = 0.007) between efficient (low-RFI) and inefficient (high-RFI) cattle regardless of diet. Furthermore, most analyzed PbAA followed the same trend as the bulk protein, with lower (P < 0.05) δ 15N values in more efficient (low-RFI) compared with less efficient (high-RFI) cattle, again regardless of diet. The only three exceptions were Phe, Met, and Lys (P > 0.05) for which the first metabolic reaction before being catabolized does not involve transamination, a pathway known naturally to enrich AAs in 15N. The contrasted isotopic signatures across RFI groups only in those PbAA undergoing transamination are interpreted as differences in transamination rates and N-use efficiency between low- and high-RFI phenotypes. Natural isotopic N signatures in bulk proteins and specific PbAA can be proposed as biomarkers of RFI in growing beef cattle fed different diets. However, the current study cannot delineate whether this effect only occurs post-absorption or to some extent also in the rumen. Our data support the conclusion that most efficient cattle in terms of RFI upregulate N conservation mechanisms compared with less efficient cattle and justify future research on this topic.

Effect of pineapple stem starch feeding on rumen microbial fermentation, blood lipid profile, and growth performance of fattening cattle.

Pineapple stem starch (PS) was evaluated for its suitability as a new starch source in concentrate for fattening cattle, based on the growth performance, blood profile, and rumen parameters of 36 steers in a 206-day feeding study. PS was formulated as a 40% concentrate and fed with forage in comparison with ground corn (GC) and ground cassava (CA) formulated at the same level. PS feeding improved weight gain and feed conversion ratio without affecting feed intake. PS did not obviously influence blood lipid profiles throughout the experiment. Ruminal concentration of total short-chain fatty acids (SCFA) increased with PS without affecting SCFA composition throughout the feeding study. Rumen amylolytic group, especially Ruminococcus bromii, was dominant in the rumen microbial community, and showed increased abundance by PS feeding throughout the experiment. These results clearly indicate the potential of PS as a useful starch source for fattening cattle in terms of rumen fermentation and growth performance.

Impact of bovine lipocalin-2 haplotype on milk composition, somatic cell score and incidence of mastitis in Polish Holstein-Friesian cattle

ABSTRACT Lipocalin-2 (LCN2) is a secreted protein, produced e.g. by neutrophils – the main group of cells involved in inflammatory conditions caused by pathogenic bacteria. So far, no studies have been carried out on the genetic variability of the LCN2 gene in cattle in terms of immunity/susceptibility to mastitis in cows. This study concerns the analysis of polymorphisms within the LCN2 gene in cattle and their impact on the production traits and the incidence of mastitis in Polish Holstein-Friesian cows. Using the PCR-RFLP method, two polymorphisms – g.98784892C > T and g.98784893T > G – were identified in intron 5 of the LCN2 gene, which represent two haplotypes (CT and TG, respectively). The CT haplotype was shown to have a significant impact on the average somatic cell score of milk, however, the CT and TG haplotypes were found to have no impact on the milk yield, protein, fat and lactose levels, or the incidence of mastitis in cows. An analysis of polymorphisms in the bovine LCN2 gene could be employed in future to support selection in dairy cattle breeding programmes focused towards the somatic cell count in milk, and the LCN2 gene itself could become a molecular marker of cows’ immunity to mastitis.

Probiotic potential of lactic acid bacteria isolates from indigenous calves is superior to isolates from crossbred dairy calves

To investigate the effect of host genetics on gut microbiota probiotic potential, we performed a comparative study between the probiotic attributes of the Lactobacilli isolated from the faeces of indigenous (Tharparkar) as well as crossbred (Vrindavani) cattle. Accordingly, 69 lactic acid bacteria (LAB) strains were isolated from faeces of new-born calves (40 from Tharparkar and 29 from Vrindavani), out of which 4 strains from each breed having auto-aggregation >40%, and cell surface hydrophobicity >70% were short-listed. The auto-aggregation and cell surface hydrophobicity values were significantly (P 0.05) to form biofilm and had comparable (P>0.05) antagonistic activity. Further assessments indicated that the per cent co-aggregation was significantly (P<0.05) higher in isolates from indigenous compared to that from the crossbred cattle. Thus, it can be concluded that LAB isolates from the indigenous Tharparkar cattle are superior over the isolates from crossbred cattle in terms of their in vitro probiotic efficacy.

The Role of Training in the Development of Beef Cattle MSME as the Economic Driving Sector of Pulubala Village, Gorontalo District, Indonesia

The purpose of this study was to analyze and describe the problem of MSMEs developing of cow livestock in Pulubala Village, Pulubala District, Gorontalo Regency; analyze and describe the potential of cow livestock in Pulubala Village and describe the role of training in MSMEs developing of cow livestock in moving the economic sector of Pulubala Village. The research design is grouped into two parts, first, identifying the various problems that exist and discussing the solution with the Focus Group Discussion (FGD) method, through this method the problems faced will be known which are then discussed solutions. Second, a short course, this activity is given to increase the knowledge and skills of the MSME community of beef cattle in terms of the method of preparing a proposal for financing. Primary and secondary data collected through questionnaires, observations, interviews and documentation, will simultaneously be analyzed by descriptive statistical analysis, which provides a description of the identity of the respondent and how the respondent assesses the role of training as a means of MSMEs developing. The results of the study show that first, the potential development of Beef Cattle in Pulubala Village, Pulubala District, Gorontalo Regency is very potential. This is indicated by an increase in the number of livestock population from year to year, the potential of land with a number of fresh production, dry production and dry matter production of 1,904,854 tons, 294,463 tons and 221,664 tons respectively, with the highest production of forage grass in Pulubala District. Second, the trainings that have been attended by farmers have an important role in MSMEs development of beef cattle in Pulubala Village, Pulubala District, Gorontalo Regency. This is indicated by the mean value of 4.13 (82.6%) in the goodcategory (category plays a role)

Vascular and morphological features of the corpus luteum 12 to 20 days after timed artificial insemination in dairy cattle

Our objective was to retrospectively compare pregnant versus nonpregnant cattle in terms of vascular and morphometric changes in corpora lutea between d 12 and 20 following timed artificial insemination (TAI). Crossbred (Gir × Holstein) lactating dairy cows (n = 136) and heifers (n = 111) were bred after synchronizing ovulations using an estradiol plus progesterone (P4)-based protocol. Corpus luteum (CL) characteristics (area, echotexture, blood flow) were recorded at 48-h intervals from d 12 to 20 following TAI using an ultrasound equipped with color Doppler. Blood samples were collected to determine CL function (plasma P4). Pregnancy diagnosis was performed at d 30. Quantitative assessment of colored pixels within the CL was performed using ImageJ software (National Institutes of Health, Bethesda, MD) and echotexture was quantified using custom software. Continuous variables such as luteal tissue area (LTA), CL blood flow (CLBF), adjusted CLBF (ratio LTA:CLBF), mean pixel value (MPV), pixel heterogeneity (HETER), and plasma P4 were analyzed retrospectively as repeated measures (d 12 to 20) in pregnant versus nonpregnant females using PROC MIXED (SAS Institute Inc., Cary, NC). Main effects were pregnancy status, day of cycle, and their interaction. Further analyses used only data from d 16, because this was the earliest time point of deviation between CLBF of pregnant and nonpregnant animals. We created quartiles for each variable and calculated the risk of pregnancy within quartile. Differences were determined using the chi-squared test. Plasma P4 was significantly higher in prospective pregnant versus nonpregnant cattle on d 18 and 20, whereas LTA differed only on d 20. On d 16, CLBF and adjusted CLBF diverged between pregnant and nonpregnant, followed by a progressive reduction in the latter until d 20. Mean pixel value was not affected by pregnancy status, but HETER was lower on d 20 in pregnant than in nonpregnant cattle. Likelihood of pregnancy increased from quartile (Q)1 (lowest values) to Q4 (highest) of CLBF (Q4 vs. Q1, odds ratio = 32.8, 95% confidence interval: 9.6 to 112.1) and adjusted CLBF [Q4 vs. Q1, odds ratio = 25.4, 95% confidence interval: 8.1 to 80.4), whereas a lower risk of pregnancy was observed only for animals within Q1 of plasma P4 [Q4 vs. Q1, odds ratio = 3.1, 95% confidence interval: 1.3 to 7.2). Day 16 quartiles of LTA, MPV, and HETER did not affect odds of pregnancy. In conclusion, we identified distinct CLBF patterns as early as 16 d after TAI and confirmed that CL function is lost by a reduction in blood flow, which precedes physical regression.

Evaluation of immune responses of stabilised SAT2 antigens of foot-and-mouth disease in cattle.

Foot-and-mouth disease (FMD) vaccines with improved stability and less reliant on a cold-chain are needed to improve the longevity of immune responses elicited in animals. This is especially so for serotypes O and SAT2 which are unstable in mildly acidic pH conditions or at elevated temperatures leading to dissociation of the capsid (146S particle) and loss of immunogenicity. Previously, stabilised SAT2 viruses were generated by reverse genetic approaches and assessed in vitro and in vivo with a guinea pig trial. Here we investigated the efficacy and comparative immunological responses of two thermostable and wild-type SAT2 vaccines over 5months followed by challenge. We assessed humoral immune responses elicited in cattle in terms of total and neutralizing antibodies and IgG1/2 isotyping; and cell-mediated responses of IFN-γ as in vitro markers of protection. Whilst there were significant differences in total and neutralizing antibodies for the vSAT2-93H group compared to other vaccinated groups after the first vaccination, there were no significant differences after the second immunization. Following intra-dermolingual challenge all vaccinated groups were fully protected as determined by the absence of generalized lesions. These results provide proof that two vaccine doses, consisting of SAT2 antigen combined with ISA206B adjuvant, administered 4-6 weeks apart were able to protect animals up to 5months pv. Additionally, vSAT2-93Y had significantly higher levels of IFN-γ after challenge and had a lower clinical score indicative of better protection compared to other vaccinated groups and the importance of cell mediated responses and antigen stability in protection.

PrP-C1 fragment in cattle brains reveals features of the transmissible spongiform encephalopathy associated PrPsc

Three different types of bovine spongiform encephalopathy (BSE) are known and supposedly caused by distinct prion strains: the classical (C-) BSE type that was typically found during the BSE epidemic, and two relatively rare atypical BSE types, termed H-BSE and L-BSE. The three BSE types differ in the molecular phenotype of the disease associated prion protein, namely the N-terminally truncated proteinase K (PK) resistant prion protein fragment (PrPres). In this study, we report and analyze yet another PrPres type (PrPres-2011), which was found in severely autolytic brain samples of two cows in the framework of disease surveillance in Switzerland in 2011. Analysis of brain tissues from these animals by PK titration and PK inhibitor assays ruled out the process of autolysis as the cause for the aberrant PrPres profile. Immunochemical characterization of the PrP fragments present in the 2011 cases by epitope mapping indicated that PrPres-2011 corresponds in its primary sequence to the physiologically occurring PrP-C1 fragment. However, high speed centrifugation, sucrose gradient assay and NaPTA precipitation revealed biochemical similarities between PrPres-2011 and the disease-associated prion protein found in BSE affected cattle in terms of detergent insolubility, PK resistance and PrP aggregation. Although it remains to be established whether PrPres-2011 is associated with a transmissible disease, our results point out the need of further research on the role the PrP-C1 aggregation and misfolding in health and disease.

Small ruminant farming and livelihood security in India: Present status and opportunities for enhancing farmers’ income

In the present paper, an attempt was made to explore the role of small ruminants rearing in livelihood and nutritional security of millions of landless, marginal and small farmers. Goat is the second largest livestock species after cattle in terms of number. Goat and sheep constitute 67.5% (135.17 million) and 32.5% (65.07 million) of total small ruminant's population (200 million) of the country respectively making 10 percent of the world small ruminant's population. Country stood second in goat and sheep population, first in goat milk production and second in goat meat and goat skin production in the world. It is an important source of income to farmers particularly in disadvantageous regions in the country where crop failure is the repeated phenomenon. Households cultivating less than 2.0 ha of land (marginal and small) are the main custodian and possess more than 76% goat and 70% of sheep population of the country, respectively. The demand for small ruminant is basically a derived demand necessitated by the demand for meat, milk, wool, hides, skins etc. High income elastic for livestock products, increasing domestic consumption due to increment in per capita income growth, variation in taste preference and urbanization are some of the driving factors of increasing demand for livestock products. The gap between demand and supply of goat meat/mutton will widen in future as meat demand may grow at faster rate than that of production. Goat milk which is also known as natural functional food contributes 4% to central milk pool (127 million tonnes).Goat based integrated livelihood models developed based on participatory research suggest that with 15 adult female goat and 25 chicks yield a net income of ₹ 82,727 per year. This model is suitable for landless and marginal group of farmers. Low cost goat technologies not only help in productivity enhancement but also improve the farmers’ price realization. Per goat per year return over variable cost was estimated to be 4800 to 5000. However, it was estimated to 4200–4500 per sheep per year. Small ruminant rearing at small scale may utilize family labour (women labour) efficiently and the problem of malnutrition in women and children may also solved. These returns may increase if farmer target festive season sale. Furthermore, through simple technological and marketing interventions- vaccination of goats, deworming, nutrition supplements, breeding with improved bucks and sale of kids at their commercial age may accrue economic gain of 5688 crore, net of cost at country level. To fetch these gains, efforts should be made to make goat farming more organized. Bridging knowledge gap, veterinary support and linking goat farmers with markets are the other key aspects for sustainable goat production and enhancing farmers’ income.

Searching for Symbolic Value of Cattle: Tropical Livestock Units, Market Price, and Cultural Value of Maasai Livestock

We examine metabolic, market, and symbolic values of livestock relative to cultural “positioning” by gender, marriage, and household production among Maasai people in Simanjiro, Tanzania to assess local “proximate currencies” relevant for “cultural success.” Data from mixed methods ethnographic research include qualitative interviews since 2012, observation of 85 livestock market sales in 2013 and 2015, and 37 short key informant interviews in 2015. We examine fit between market values, Tropical Livestock Units (TLU, weight-based species exchange ratio), and perceived value from interviews for moran (unmarried men), muruo (married men), and tɔmɔnɔ́k (married women). Hedonic regression using livestock species, sex, maturity, and size accounted for 90% of the local market price of livestock. We compared the market-based exchange ratio between cattle and smallstock (sheep and goats) to TLU and perceived values situating symbolic value of cattle in terms of Maasai household production schema. One TLU model accurately predicted market exchange ratios, while another predicted hypothetical exchanges, suggesting need for improved livestock wealth estimation for pastoralists. Ritual context, subsistence work, and cultural position influenced perceived values: Moran overvalued cattle by 100% of the local market value. Tɔmɔnɔ́k accurately perceived the market exchange ratio despite never directly engaging in livestock market transactions. Muruo perceived exchange ratios intermediate between moran and tɔmɔnɔ́k. We argue that these perceptions of value reflect distinct labor responsibilities of moran, muruo, and tɔmɔnɔ́k in livestock management, differential value of bridewealth, and control of meat and milk.Attention to value of different livestock species in cultural models of production may prove useful for development efforts.

The anatomy of the bifurcated neural spine and its occurrence within Tetrapoda.

Vertebral neural spine bifurcation has been historically treated as largely restrictive to sauropodomorph dinosaurs; wherein it is inferred to be an adaptation in response to the increasing weight from the horizontally extended cervical column. Because no extant terrestrial vertebrates have massive, horizontally extended necks, extant forms with large cranial masses were examined for the presence of neural spine bifurcation. Here, I report for the first time on the soft tissue surrounding neural spine bifurcation in a terrestrial quadruped through the dissection of three Ankole-Watusi cattle. With horns weighing up to a combined 90 kg, the Ankole-Watusi is unlike any other breed of cattle in terms of cranial weight and presence of neural spine bifurcation. Using the Ankole-Watusi as a model, it appears that neural spine bifurcation plays a critical role in supporting a large mobile weight adjacent to the girdles. In addition to neural spine bifurcation being recognized within nonavian dinosaurs, this vertebral feature is also documented within many members of temnospondyls, captorhinids, seymouriamorphs, diadectomorphs, Aves, marsupials, artiodactyls, perissodactyls, and Primates, amongst others. This phylogenetic distribution indicates that spine bifurcation is more common than previously thought, and that this vertebral adaptation has contributed throughout the evolutionary history of tetrapods. Neural spine bifurcation should now be recognized as an anatomical component adapted by some vertebrates to deal with massive, horizontal, mobile weights adjacent the girdles.

Bovine Viral Diarrhoea Virus (BVDV) in Dairy Cattle: A Matched Case-Control Study

Bovine viral diarrhoea virus (BVDV) causes one of the most important diseases of cattle in terms of economic costs and welfare. The aims were to estimate herd prevalence and to investigate the factors associated with antibodies in bulk tank milk (BTM) in dairy herds through a matched case-control study. To estimate herd prevalence, BTM samples were randomly selected (n = 314) from a population (N = 1604). The true prevalence of BVDV was 24.3% (CI 95% = 20.1-29.3%). For the case-control study, BVDV antibody-positive herds (high antibody titres) were classified as cases (n = 21) and matched (n = 63) by milk production with herds presenting low antibody titres (ratio of 1 : 3). Three multivariable models were built: 1) full model, holding all 21 variables, and two models divided according to empirical knowledge and similarity among variables; 2) animal factor model; and 3) biosecurity model. The full model (model 1) identified: age as a culling criteria (OR = 0.10; CI 95% = 0.02-0.39; P < 0.01); farms that provided milk to other industries previously (OR = 4.13; CI 95% = 1.17-14.49; P = 0.02); and isolation paddocks for ill animals (OR = 0.14; CI 95% = 0.01-0.26; P = 0.02). The biosecurity model revealed a significant association with the use of natural mating (OR = 9.03; CI 95% = 2.14-38.03; P < 0.01); isolation paddocks for ill animals (OR = 0.06; CI 95% = 0.05-0.83; P = 0.03); years providing milk for the same industry (OR = 0.94; CI 95% = 0.91-0.97; P = 0.02); and direct contact over fences among cattle of neighbouring farms (OR = 5.78; CI 95% = 1.41-23.67; P = 0.04). We recommend the application of grouping predictors as a good choice for model building because it could lead to a better understanding of disease-exposure associations.

돼지사료 중의 다이옥신 잔류 평가

ABSTRACTDioxins are chemical substances that are not properly decomposed degradation under natural photochemical, biological and chemical conditions in the environment, and bio-accumulate through the food chain, so pose a risk of causing adverse effects to human health and the environment. Ninety seven percent of human exposure to dioxins comes through meat, fish, dairy consumption and so on. Pork is the largest proportion meat aspect of daily intake in the Korean food. Pigs are three times more than Cattle in terms of breeding population and production amount in the world, and the amount is increasing every year. Therefore, it is necessary to monitor the exposure level of dioxins in pig’s body. Also, it is required to evaluate the presence of these chemical substances in the pig’s feed grain such as corn, soybeans, and tallow. The purpose of this study was to evaluate PCDD/Fs in pig's feed to search the origin of PCDD/Fs. Feed samples obtained were wheat from East Europe, corn from South America and America, soybean meal from Korea, America, South America and India and tallow from Korea. The preparation of samples was based on the EPA method 1613. Instrumental analysis was based on the use of high resolution gas chromatography coupled to high resolution mass spectrometry (HRGC/HRMS). The concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and 1,2,3,7,8-pentachlorodibenzo-p-dioxin (PCDD), which are the most toxic potent dioxins, were not observed in any of the samples. However OCDD was detected in most of the samples. The TEQs in the feed samples were ranged from 0 pg TEQ/g to 0.09841 pg TEQ/g. Especially, the high level of TEQs was observed in the samples of wheat from East Europe and soybean meal from Korea.Key words: PCDD/Fs, HRGC/HRMS, feed, EPA method 1613

PRNP gene variation in Pakistani cattle and buffaloes

Bovine spongiform encephalopathy (BSE) is a neurodegenerative prion protein misfolding disorder of cattle. BSE is of two types, classical BSE and atypical BSE which in turn is of two types, H-type BSE and L-type BSE. Both H-type BSE and L-type BSE are primarily sporadic prion disorders. However, one case of H-type BSE has recently been associated with E211K polymorphism in the prion protein gene (PRNP). Two polymorphisms in the bovine PRNP are also associated with susceptibility to classical BSE: a 23bp insertion/deletion (indel) in the PRNP promoter region and a 12bp indel in the first intron. No information regarding BSE susceptibility in Pakistani cattle is available. The present study aimed at achieving this information. A total of 236 cattle from 7 breeds and 281 buffaloes from 5 breeds were screened for E211K polymorphism and 23bp and 12bp indels employing triplex PCR. The E211K polymorphism was not detected in any of the animals studied. The 23bp insertion allele was underrepresented in studied cattle breeds while the 12bp insertion allele was overrepresented. Both 23bp and 12bp insertion alleles were overrepresented in studied buffalo breeds. Almost 90% of alleles were insertion alleles across all studied buffalo breeds. The average frequency of 23bp and 12bp insertion alleles across all studied cattle breeds was found to be 0.1822 and 0.9407, respectively. There were significant differences between Pakistani and worldwide cattle in terms of allele, genotype and haplotype frequencies of 23bp and 12bp indels. The higher observed frequency of 12bp insertion allele suggests that Pakistani cattle are relatively more resistant to classical BSE than European cattle. However, the key risk factor for classical BSE is the dietary exposure of cattle to contaminated feedstuffs.

Heritability and genetic correlation of production and reproduction traits of Simmental cows

Improvement of production capacity of cattle in terms of increasing the production of milk, milk fat and number of calves, greatly depends on phenotype and genotype variability, heritability and correlation between desirable traits, as well as on the production level of the cattle population. Heritability, as a value expressing and measuring average additive gene effect, is one of the major characteristic of quantitative traits from the point of view of creating genetically high-value cattle populations. Knowledge of the heritability is necessary in the estimation of the beeeding value of cattle and has significant impact on the selection of breeding method. Genetic correlations are very important in indirect selection where changes in one trait are induced through selection of other traits between which a genetic correlation exists. Genetic correlations can be determined in all cases where heritability coefficient can be calculated. This research included 3.461 first calving Simmental cows under control, with lactation concluded within one year. All first-calvers were reared on individual farms in the territory of Republic of Serbia. In this study, heritability and genetic correlations between the the following milk and fertility traits were investigated: duration of lactation (days)- DL, milk yield in standard lactation (kg)- MY, milk fat content in standard lactation (%)- MFC, milk fat yield in standard lactation (kg)- MFY, yield of 4% FCM in standard lactation (kg)- 4%FCM, age at first calving (days)- AC and duration of service period (days)- DSP.