Use of milk samples from a milk evaluation program for the genotyping of cows

Abstract. Milk can be an attractive DNA-resource for genotyping milking cows, e.g. for paternity control or QTL analysis within a daughter design. The use of milk collected within the established milk evaluation programs enables the collection of large numbers of samples. Nevertheless, there are limitations when using the remedies of tested milk samples, e.g. permutations of samples or partially degraded DNA. A DNA preparation method suitable for samples from routine milk recording has been developed that combines an initial centrifugation step with direct lysis of cells and purification from comparatively high volumes by using silica membrane spin columns. The method yields high quality genomic DNA from fresh samples and PCR grade DNA from remedies of tested samples. In addition the potential use of milk samples within a daughter design was evaluated. We collected reference samples from 119 Simmental dairy cows from 6 half sib families. From 89 of these dairy cows remedies of milk samples were obtained from the routine milk laboratory. Paternity could be established by microsatellite analyses for all 119 reference cases. From the 89 milk laboratory samples 86 were successfully microsatellite typed. In 81 cases the genotypes from milk and reference sample were identical. In summary it could be shown that it is possible to genotype dairy cows from test laboratory milk samples, but results have to be used carefully taking into account inherent limitations. The use of milk as compared with tissue samples as a source for DNA within daughter designs is discussed.

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THE DETECTION OF ABNORMAL COW'S MILK BY MICROSCOPIC METHODS

Canadian Journal of Research ◽

10.1139/cjr39d-024 ◽

1939 ◽

Vol 17d (11) ◽

pp. 225-244 ◽

Cited By ~ 4

Author(s):

Seymour Hadwen ◽

Ronald Gwatkin

Keyword(s):

Dairy Cows ◽

Cellular Responses ◽

Degenerative Changes ◽

Polymorphonuclear Cells ◽

Polymorphonuclear Leucocytes ◽

Milk Samples ◽

Large Numbers ◽

Resistance To Infection ◽

Mononuclear Leucocytes ◽

Micro Organisms

A large number of milk samples from dairy cows have been studied microscopically and culturally, the object being to estimate the numbers of body cells and leucocytes present.The Breed and sediment counts are compared. The latter is preferred because it furnishes more information than mere enumeration of the cells. In a sediment smear a complete picture of conditions in the udder may be visualized, including the various cellular responses to the organisms causing mastitis. Estimates of the numbers of cells present are sufficient for a diagnosis when accompanied by the information gained in examining the smear.Differential counts were made for special purposes only, such as to define normality in milk. In defining normal milk, a standard was set which did not tolerate the presence of micro-organisms or polymorphonuclear leucocytes in the samples. In a herd of 60 cows, milk from 9 young cows met this standard. Diphtheroids occurred in 70% of the cows. In comparison with the clean cows, the diphtheroid carriers had larger numbers of polymorphonuclear leucocytes.In staphylococcic mastitis the leucocytes are often very numerous, and this may persist for months. Staphylococcic infections cause a great influx of large, ring-shaped polymorphonuclear leucocytes. The cocci can generally be found on the smears. Sometimes, when leucocytes are scarce, cocci occur in very large numbers.In streptococcic mastitis the mononuclear leucocytes are numerous. Loose, irregular clumping is commonly seen, and the polymorphonuclear leucocytes often clump separately. Leucocytes are not as numerous as in staphylococcic cases, but the percentage of the mononuclear leucocytes is higher. Tables showing the increase and decrease of the leucocytes indicate that when they are numerous the infective organisms may be scarce or absent, the reverse being also true. Streptococcic mastitis is sometimes a difficult disease to diagnose microscopically, on account of scarcity of organisms. Various ways of finding the cocci are discussed.The diagnosis of B. coli and Corynebacterium pyogenes mastitis is described. Both these organisms may cause severe lesions, and consequently the smears reveal extensive degenerative changes in the leucocytes. The organisms are present in large numbers. B. coli and C. pyogenes infections produce a different leucocytic picture under the microscope than do pyogenic cocci. The effect of these infections is generally more destructive.A study of phagocytosis in diseases of the udder furnishes valuable aid in determining the degree of resistance to infection on the part of the host.Red blood corpuscles in milk may be unaccompanied by any signs of infection. Chromatin-staining granules in milk are caused by degenerative changes in the polymorphonuclear cells. Calcium calculi are found both in the tissues and in the milk. A study of over 20 samples of colostrum is recorded.

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Relationships between milk yield, quality and coagulation properties with kappa-casein (к-CN) genotypes of Bulgarian Rhodope cattle breed

Agricultural Science and Technology ◽

10.15547/ast.2019.03.034 ◽

2019 ◽

Vol 11 (3) ◽

pp. 203-206

Author(s):

I. Mehandzhiyski ◽

Т. Angelova ◽

D. Yordanova ◽

J. Krastanov

Keyword(s):

Dairy Cows ◽

Protein Content ◽

Milk Yield ◽

Tissue Sample ◽

Milk Proteins ◽

Coagulation Time ◽

Tissue Samples ◽

Milk Samples ◽

Rennet Coagulation ◽

Yield Quality

Abstract. The aim of the present study was to establish the association between different к-CN genotypes with milk yield, quality and coagulation properties in dairy cows of Bulgarian Rhodope breed. For determination of milk proteins polymorphism and its relationship with individual coagulation properties of milk and its quality, 136 milk samples from Bulgarian Rhodope dairy cows reared in 4 farms were collected. The visit to the farms and the taking of the milk samples took place between May and June 2009. Animal milk is based on daily milking on the relevant control day of the current lactation. During the morning milking, 50mL samples were collected without preservative, stored in cooling bags and analyzed in the specialized lab at the Agricultural Institute, Stara Zagora by Computerized Renneting Metter. The evaluated parameters of milk coagulation properties were: rennet coagulation time (RCT, min); curd firming time (K20, min) and curd firmness (A30, mm). Milk proteins polymorphism was identified by tissue samples collection from 136 cows. To this end, specialized pliers and marks with a vial containing desiccant were used. With this technique, the tissue sample is obtained and sealed at the time of identification of the animal. After collection, tissue samples were shipped to the University in Padova, Italy for PCR-RFLP analysis. DNA was purified using a Maxwell®16 Tissue DNA purification kit (Promega) according to the manufacturer’s instructions. Data were analyzed using descriptive statistical analysis (SYSTAT 13). The results obtained give reason to the following conclusions: The highest milk yield was established in cows from the AH genotype – 16kg, whereas the lowest value was detected in cows from the BH genotype – 12.83kg. Homozygous cows from the BB genotype produced milk with the highest fat content – 5.11%, whereas heterozygous from the BH genotype: milk with the lowest protein content – 3.16%. The cows from the AH genotypes were outlined with the lowest milk fat and protein content. The longest rennet coagulation time (RCT) was observed in АА and АН genotypes, the longest curd firming time (К20) – in genotype AH, the highest curd firmness (А30) – in the milk of cows from the AB and BB genotypes.

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Relationships among macro-minerals, other selected serum markers of bone profile and milk components of dairy cows during late-lactation

Annals of Animal Science ◽

10.2478/aoas-2020-0094 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Ryszard Mordak ◽

Zbigniew Dobrzański ◽

Robert Kupczyński

Keyword(s):

Dairy Cows ◽

Milk Fat ◽

Dry Matter ◽

Inorganic Phosphorus ◽

Serum Markers ◽

Laboratory Diagnostics ◽

Lactation Period ◽

Milk Samples ◽

Milk Components ◽

Macro Mineral

AbstractTesting blood and milk parameters as well as analysing the relationships among these markers is very useful for monitoring the internal homeostasis and health in high-yielding dairy cows during various production periods. The aim of the study was to assess the correlations (relationships) among macro-minerals, such as calcium (Ca), inorganic phosphorus (P), magnesium (Mg), other selected bone profile markers, such as total protein (TP), albumin, activity of alkaline phosphatase (ALP) measured in serum and selected milk components such as number of somatic cells (SCC), colony-forming units (CFU), milk fat (MF), milk protein (MP), milk lactose (ML), dry matter (DM), non-fat dry matter (FDM) and milk production in late-lactation cows. Both blood and milk samples were collected from 11 clinically healthy milking cows during the late-lactation period. The cows were examined once a day for 3 consecutive days resulting in 33 sets of blood and milk samples for laboratory and statistical analysis. Significant correlations were observed between: Mg and MP, Mg and FDM, ALP and SCC, TP and SCC, TP and MP, TP and FDM, albumin and MP, albumin and FDM, P and Mg, Mg and albumin, and between TP and albumin. When monitoring macro-mineral homeostasis and mammary gland health, especially in intensively fed high-yielding dairy cows correlations between these markers should be considered. The revealed correlations can allow for deeper comparative laboratory diagnostics of homeostasis and can be especially useful for laboratory monitoring of the potential risk of subclinical macro-mineral deficiency in high-yielding dairy cows.

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Fourier transform infrared spectroscopy of milk samples as a tool to estimate energy balance, energy- and dry matter intake in lactating dairy cows

Journal of Dairy Research ◽

10.1017/s0022029920001004 ◽

2020 ◽

pp. 1-8

Author(s):

Amira Rachah ◽

Olav Reksen ◽

Nils Kristian Afseth ◽

Valeria Tafintseva ◽

Sabine Ferneborg ◽

...

Keyword(s):

Dairy Cows ◽

Dry Matter ◽

External Validation ◽

Ftir Spectra ◽

Dry Matter Intake ◽

Energy Status ◽

Test Set ◽

Milk Samples ◽

External Test ◽

Body Energy

Abstract The objective of the study was to evaluate the potential of Fourier transform infrared spectroscopy (FTIR) analysis of milk samples to predict body energy status and related traits (energy balance (EB), dry matter intake (DMI) and efficient energy intake (EEI)) in lactating dairy cows. The data included 2371 milk samples from 63 Norwegian Red dairy cows collected during the first 105 days in milk (DIM). To predict the body energy status traits, calibration models were developed using Partial Least Squares Regression (PLSR). Calibration models were established using split-sample (leave-one cow-out) cross-validation approach and validated using an external test set. The PLSR method was implemented using just the FTIR spectra or using the FTIR together with milk yield (MY) or concentrate intake (CONCTR) as predictors of traits. Analyses were conducted for the entire first 105 DIM and separately for the two lactation periods: 5 ≤ DIM ≤ 55 and 55 < DIM ≤ 105. To test the models, an external validation using an independent test set was performed. Predictions depending on the parity (1st, 2nd and 3rd-to 6th parities) in early lactation were also investigated. Accuracy of prediction (r) for both cross-validation and external test set was defined as the correlation between the predicted and observed values for body energy status traits. Analyzing FTIR in combination with MY by PLSR, resulted in relatively high r-values to estimate EB (r = 0.63), DMI (r = 0.83), EEI (r = 0.84) using an external validation. Only moderate correlations between FTIR spectra and traits like EB, EEI and dry matter intake (DMI) have so far been published. Our hypothesis was that improvements in the FTIR predictions of EB, EEI and DMI can be obtained by (1) stratification into different stages of lactations and different parities, or (2) by adding additional information on milking and feeding traits. Stratification of the lactation stages improved predictions compared with the analyses including all data 5 ≤ DIM ≤105. The accuracy was improved if additional data (MY or CONCTR) were included in the prediction model. Furthermore, stratification into parity groups, improved the predictions of body energy status. Our results show that FTIR spectral data combined with MY or CONCTR can be used to obtain improved estimation of body energy status compared to only using the FTIR spectra in Norwegian Red dairy cattle. The best prediction results were achieved using FTIR spectra together with MY for early lactation. The results obtained in the study suggest that the modeling approach used in this paper can be considered as a viable method for predicting an individual cow's energy status.

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Prevalence of Mastitis and Antibiotic Resistance of Bacterial Isolates from CMT Positive Milk Samples Obtained from Dairy Cows, Camels, and Goats in Two Pastoral Districts in Southern Ethiopia

Animals ◽

10.3390/ani11061530 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1530

Author(s):

Amanuel Balemi ◽

Balako Gumi ◽

Kebede Amenu ◽

Sisay Girma ◽

Muuz Gebru ◽

...

Keyword(s):

Antibiotic Resistance ◽

Dairy Cows ◽

Raw Milk ◽

Multidrug Resistant ◽

Southern Ethiopia ◽

Resistant Bacteria ◽

Coagulase Negative Staphylococcus ◽

Bacterial Isolates ◽

E Coli ◽

Milk Samples

A study was carried out from August 2017 to February 2018 on lactating dairy cows, one-humped dromedary camels, and goats to determine mastitis in the Bule Hora and Dugda Dawa districts of in Southern Ethiopia. Milk samples from 564 udder quarters and udder halves from 171 animals consisting of 60 dairy cows, 51 camels, and 60 goats were tested for mastitis. Sixty-four positive udder milk samples were cultured, and bacterial mastitis pathogens were isolated and identified. The antibiotic resistance of bacterial isolates from milk with mastitis was tested against nine antimicrobials commonly used in the study area. Cow- and quarter-level prevalence of mastitis in dairy cows, camels, and goats was 33.3%, 26.3%, and 25% and 17.6%, 14.5%, and 20%, respectively. In cattle, the prevalence was significantly higher in Dugda Dawa than in Bule Hora. Major bacterial isolates were coagulase-negative Staphylococcus species (39.1%), S. aureus (17.2%), S. hyicus (14.1%), and S. intermedius and Escherichia coli (9.4% each). In camels, udder abnormality and mastitis were significantly higher in late lactation than in early lactation. Mastitis tends to increase with parity in camels. E. coli isolates were highly resistant to spectinomycin, vancomycin, and doxycycline, whereas most S. aureus isolates were multidrug-resistant. Most of the rural and periurban communities in this area consume raw milk, which indicates a high risk of infection with multidrug-resistant bacteria. We recommend a community-focused training program to improve community awareness of the need to boil milk and the risk of raw milk consumption.

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Occurrence of abortions induced by Neospora caninum in dairy cattle from Santa Catarina, southern Brazil

Revista Brasileira de Parasitologia Veterinária ◽

10.1590/s1984-29612017051 ◽

2017 ◽

Vol 26 (3) ◽

pp. 292-298 ◽

Cited By ~ 7

Author(s):

Cesar Augusto Barbosa de Macedo ◽

Madlaine Frigo Silveira Barbosa de Macedo ◽

Ana Carolina Miura ◽

Alessandra Taroda ◽

Sergio Tosi Cardim ◽

...

Keyword(s):

Dairy Cattle ◽

Dairy Cows ◽

High Frequency ◽

Neospora Caninum ◽

Enzyme Linked Immunosorbent Assay ◽

Southern Brazil ◽

Chain Reaction ◽

Santa Catarina ◽

Tissue Samples ◽

Polymerase Chain

Abstract The aim of the present study was to investigate the occurrence of N. caninum associated with abortions of dairy cattle from Santa Catarina state, southern Brazil by using enzyme-linked immunosorbent assay (ELISA), immunohistochemistry (IHC), and polymerase chain reaction (PCR). Blood from dairy cows that aborted along with intrathoracic fluid and tissue samples (brain, heart, liver, and lung) from their fetuses were collected and used for serology; PCR, histopathological, and immunohistochemistry (IHC) evaluations were also conducted. Twenty-one cows (51.2%) out of 41, and eight fetuses (26.7%) out of 30 were ELISA (HerdCheck, IDEXX) positive for N. caninum. Dams > 36 months of age had a higher risk of being serum positive than younger animals. PCR and IHC revealed that 38.8% (14/36) and 25.0% (9/36) of the fetuses were positive for N. caninum, respectively for each of the tests. Seropositive cows had a higher frequency of fetuses that were also positive by either intrathoracic fluid, PCR, or IHC. In summary, the present study observed a high frequency of N. caninum in abortions from dairy cows from southern Brazil, with a higher N. caninum prevalence found in cows that were older than 36 months. In addition, serology, PCR, and IHC should be used all together for better diagnosis of neosporosis in cattle.

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Weekly excretion of the mammalian lignan enterolactone in milk of dairy cows fed flaxseed meal

Journal of Dairy Research ◽

10.1017/s0022029909990082 ◽

2009 ◽

Vol 76 (4) ◽

pp. 455-458 ◽

Cited By ~ 11

Author(s):

Nathalie Gagnon ◽

Cristiano Côrtes ◽

Hélène V Petit

Keyword(s):

Mammary Gland ◽

Dairy Cows ◽

Baseline Level ◽

Significant Interaction ◽

Control Diet ◽

Secoisolariciresinol Diglucoside ◽

Milk Samples ◽

Flaxseed Meal ◽

Ruminal Microbiota ◽

Feeding Regimen

Flaxseed meal (FM) is rich in the plant lignan secoisolariciresinol diglucoside (SDG) which is converted to the mammalian lignans enterodiol and enterolactone (EL) by ruminal microbiota. Feeding FM to dairy cows increases linearly EL concentration in milk but enterodiol is not detected. The objectives of the study were to determine the length of time to obtain peak EL concentration in the milk of dairy cows fed 20% FM and the length of time to return to EL baseline level in milk when cows are switched from high to low intake of flax SDG. A total of 12 multiparous lactating Holstein cows were assigned randomly to one of two feeding regimens: the control (CO) diet was fed for 6 weeks or the FM diet was fed from week 0 to 3 inclusive and then cows were switched to the control diet from week 3 to 6 inclusive. Milk samples were taken weekly for EL analysis. There was a significant interaction between feeding regimen and week for milk concentration of EL as a result of higher concentration of EL from week 1 to 3 for cows on the FM regimen compared with those on the CO regimen. Concentrations of milk EL on the FM regimen maintained uniform high levels from week 1 to 3 and they decreased significantly from week 3 to 4 when the CO diet was reintroduced in week 3. This study suggests that the conversion of SDG to the mammalian lignan EL and the transfer of EL to the mammary gland are well established after one week of feeding 20% FM in the diet of dairy cows and that milk concentration of EL returns to baseline level after one week of FM deprivation.

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Molecular characterization of virulence factors in Staphylococcus aureus isolated from bovine subclinical mastitis in central Ethiopia

Annals of Microbiology ◽

10.1186/s13213-021-01639-3 ◽

2021 ◽

Vol 71 (1) ◽

Author(s):

Desiye Tesfaye Tegegne ◽

Gezahegne Mamo ◽

Hika Waktole ◽

Yohannes Equar Messele

Keyword(s):

Staphylococcus Aureus ◽

Dairy Cows ◽

Virulence Factors ◽

Virulence Genes ◽

Animal Health ◽

Subclinical Mastitis ◽

Biochemical Tests ◽

Milk Samples ◽

Lactating Dairy Cows ◽

Genomic Study

Abstract Purpose Staphylococcus aureus (S. aureus) is the most important pathogen involved in bovine mastitis in dairy production. S. aureus produces a spectrum of extracellular protein toxins and virulence factors which are thought to contribute to the pathogenicity of the organism. The aim of this work was to isolate and molecular characterize S. aureus associated with bovine subclinical mastitis in the central part of Ethiopia. Methods A total of 265 lactating dairy cows from various dairy farms in four different geographical locations were screened by the California mastitis test (CMT) for bovine subclinical mastitis. One hundred thirty CMT-positive milk samples were collected and transported to the laboratory. Different biochemical tests and polymerase chain reaction (PCR) were used for the identification of S. aureus isolates. Finally, PCR was performed for molecular detection of virulence genes. Results From a total of 265 lactating dairy cows screened, 49% (n = 130) were positive for bovine subclinical mastitis. One hundred thirty mastitic milk samples were subjected to bacterial culturing, and one hundred (76%) S. aureus isolates were identified based on phenotypic characters. Sixty-eight confirmed S. aureus isolates were obtained using PCR. The confirmed S. aureus isolates were tested for six virulence genes (tsst-1, hlb, eta, sea, clfA, and icaD) using PCR. Of the six virulence genes screened from all the isolates, only two (clfA and eta) were detected in the isolates. Out of 68 isolates, 25% and 22% were possessed the eta and clfA genes, respectively. Conclusion The presence of Staphylococcus aureus having virulence genes (eta and clfA) revealed that mastitis is a major concern nowadays affecting animal health, milk quality, and yield. Further genomic study of these isolates will provide broad new insights on virulence.

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Withdrawal of cefoperazone with milk after intramammary administration in dairy cows – prospective and retrospective analysis

Polish Journal of Veterinary Sciences ◽

10.1515/pjvs-2017-0031 ◽

2017 ◽

Vol 20 (2) ◽

pp. 261-268

Author(s):

A. Burmańczuk ◽

T. Grabowski ◽

T. Błądek ◽

C. Kowalski ◽

P. Dębiak

Keyword(s):

Dairy Cows ◽

Half Life ◽

Drug Distribution ◽

Compartment Model ◽

Clinical Mastitis ◽

Pharmacokinetic Analysis ◽

Pharmacokinetic Parameters ◽

Lactation Period ◽

Milk Samples ◽

Drug Concentrations

Abstract The aim of the study was to carry out retrospective and prospective comparative analyses of the pharmacokinetics of CEF after single intramammary (IMM) administration in cows. The prospective study (study A) was conducted on 9 dairy cows of the Polish Black-White race with clinical mastitis during the lactation period. Milk samples were collected at 2, 4, 6, 8, 10, 24, 36, 48, 72 and 84 h after single IMM administration of 250 mg of CEF to one quarter. Drug concentrations in milk samples were determined by HPLC-MS/MS technique and the results of the pharmacokinetic analysis were compared to those obtained in previous studies based on the microbiological (study B) and HPLC-UV methods (study C and D). Pharmacokinetic parameters were calculated based on adapted two-compartment model of drug distribution. One of the findings of the comparison of the analysed investigations is that the CEF kinetics determined with the microbiological method is consistent with the results obtained by the authors of this paper. Both studies yielded similar results of the key pharmacokinetic parameters related to the level of the drug distribution to tissues and elimination half-life. In the pharmacodynamic analysis, the observations in all four studies were entirely consistent and have shown lower values of T>MIC90 in healthy animals and significantly higher values in infected dairy cows. The comparison of studies A, B, C, and D revealed that the time of complete CEF wash-out of 90.90% varied and amounted to 5.7, 8.0, 2.2, and 2.2 days after administration of the drug, respectively. It was confirmed that not only the type of the analytical method but also correct sampling have a significant impact on determination of the correct value of the drug half-life after IMM administration. The comparative analysis of studies in which the milk yield was high and low allows a conclusion that this parameter in the case of CEF has no significant effect on T>MIC90.

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