scholarly journals Genetic Parameters of Bovine Milk Fatty Acid Profile, Yield, Composition, Total and Differential Somatic Cell Count

Animals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2406
Author(s):  
Tania Bobbo ◽  
Mauro Penasa ◽  
Martino Cassandro
Keyword(s):  
Animal Models ◽  
Somatic Cell ◽  
Cell Count ◽  
Milk Yield ◽  
Milk Fat ◽  
Fixed Effects ◽  
Somatic Cell Count ◽  
Genetic Parameters ◽  
Genetic Correlations ◽  
Bovine Milk

The growing interest of consumers for milk and dairy products of high nutritional value has pushed researchers to evaluate the feasibility of including fatty acids (FA) in selection programs to modify milk fat profile and improve its nutritional quality. Therefore, the aim of this study was to estimate genetic parameters of FA profile predicted by mid-infrared spectroscopy, milk yield, composition, and total and differential somatic cell count. Edited data included 35,331 test-day records of 25,407 Italian Holstein cows from 652 herds. Variance components and heritability were estimated using single-trait repeatability animal models, whereas bivariate repeatability animal models were used to estimate genetic and phenotypic correlations between traits, including the fixed effects of stage of lactation, parity, and herd-test-date, and the random effects of additive genetic animal, cow permanent environment and the residual. Heritabilities and genetic correlations obtained in the present study reflected both the origins of FA (extracted from the blood or synthesized de novo by the mammary gland) and their grouping according to saturation or chain length. In addition, correlations among FA groups were in line with correlation among individual FA. Moderate negative genetic correlations between FA and milk yield and moderate to strong positive correlations with fat, protein, and casein percentages suggest that actual selection programs are currently affecting all FA groups, not only the desired ones (e.g., polyunsaturated FA). The absence of association with differential somatic cell count and the weak association with somatic cell score indicate that selection on FA profile would not affect selection on resistance to mastitis and vice versa. In conclusion, our findings suggest that genetic selection on FA content is feasible, as FA are variable and moderately heritable. Nevertheless, in the light of correlations with other milk traits estimated in this study, a clear breeding goal should first be established.

scholarly journals Genetic parameters of the linear body conformation traits and genetic correlations with udder traits, milk yield and composition, and somatic cell count in dairy ewes

2011 ◽  
Vol 91 (4) ◽  
pp. 585-591 ◽  
Author(s):  
L. Fernando de la Fuente ◽  
Carlos Gonzalo ◽  
Juan Sánchez ◽  
Roberto Rodríguez ◽  
Juan Carriedo ◽  
...  
Keyword(s):  
Somatic Cell ◽  
Cell Count ◽  
Milk Yield ◽  
Somatic Cell Count ◽  
Genetic Parameters ◽  
Genetic Correlations ◽  
Dairy Sheep ◽  
General Body ◽  
Body Conformation ◽  
Linear Body

de la Fuente, L. F., Gonzalo, C., Sánchez, J. P., Rodríguez, R., Carriedo, J. A. and San Primitivo, F. 2011. Genetic parameters of the linear body conformation traits and genetic correlations with udder traits, milk yield and composition, and somatic cell count in dairy ewes. Can. J. Anim. Sci. 91: 585–591. This study was designed to estimate the inheritance of linear body conformation traits and their genetic correlations with linear udder traits, milk yield and composition, and somatic cell count (SCC) in dairy sheep. A total of 10 189 records of five body conformation traits, five linear udder traits, milk yield, protein and fat content, and SCC were obtained from 3977 adult ewes that were daughters of 268 sires belonging to 23 commercial flocks enrolled in the Churra breed selection nucleus. All type traits were scored on a nine-point linear scale. Genetic correlations and heritabilities were estimated using a repeatability multitrait animal model. Body conformation (stature, rear leg-rear view, feet angle, rump width, and general body score) had heritabilities (0.19, 0.18, 0.24, 0.14 and 0.17) and repeatabilities (0.34, 0.42, 0.42, 0.36, and 0.35), which indicate good potential for selection. For udder traits (udder depth, udder attachment, teat placement, teat length and udder shape) heritabilities varied between 0.09 and 0.26, and repeatabilities between 0.35 and 0.53. General body score (composite trait) had high phenotypic and genetic correlations with rear leg-rear view (0.64 and 0.80) and rump width (0.42 and 0.58). The phenotypic and genetic correlation between general body score and udder shape (composite trait) was 0.23 and 0.44, respectively. In addition, phenotypic and genetic correlations between body conformation traits and milk yield, protein and fat percentages, and SCC were low in most cases; therefore, no significant correlated genetic response is expected in body conformation traits when selecting for milk yield, protein and fat percentages, and SCC variables, in Churra breed. In conclusion, the heritability and repeatability values found in this study for body conformation traits, combined with the ease of recording by linear scale, make improvement by selection possible in dairy sheep.

scholarly journals Effect of Pregnancy, Milk Yield, and Somatic Cell Count on Bovine Milk Fat Hydrolysis

1988 ◽  
Vol 71 (4) ◽  
pp. 925-931 ◽  
Author(s):  
K.C. Bachman ◽  
M.J. Hayen ◽  
D. Morse ◽  
C.J. Wilcox
Keyword(s):  
Somatic Cell ◽  
Cell Count ◽  
Milk Yield ◽  
Milk Fat ◽  
Somatic Cell Count ◽  
Bovine Milk ◽  
Fat Hydrolysis

scholarly journals Hyperketonemia Predictions Provide an On-Farm Management Tool with Epidemiological Insights

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1291
Author(s):  
Ryan S. Pralle ◽  
Joel D. Amdall ◽  
Robert H. Fourdraine ◽  
Garrett R. Oetzel ◽  
Heather M. White
Keyword(s):  
Somatic Cell ◽  
Cell Count ◽  
Milk Yield ◽  
Milk Fat ◽  
Somatic Cell Count ◽  
Past Research ◽  
Management Tool ◽  
Milk Analysis ◽  
Linear Regression Models ◽  
High Throughput Detection

Prediction of hyperketonemia (HYK), a postpartum metabolic disorder in dairy cows, through use of cow and milk data has allowed for high-throughput detection and monitoring during monthly milk sampling. The objective of this study was to determine associations between predicted HYK (pHYK) and production parameters in a dataset generated from routine milk analysis samples. Data from 240,714 lactations across 335 farms were analyzed with multiple linear regression models to determine HYK status. Data on HYK or disease treatment was not solicited. Consistent with past research, pHYK cows had greater previous lactation dry period length, somatic cell count, and dystocia. Cows identified as pHYK had lower milk yield and protein percent but greater milk fat, specifically greater mixed and preformed fatty acids (FA), and greater somatic cell count (SCC). Differential somatic cell count was greater in second and fourth parity pHYK cows. Culling (60d), days open, and number of artificial inseminations were greater in pHYK cows. Hyperketonemia prevalence decreased linearly in herds with greater rolling herd average milk yield. This research confirms previously identified risk factors and negative outcomes associated with pHYK and highlights novel associations with differential SCC, mixed FA, and preformed FA across farm sizes and production levels.

RELATIONSHIPS BETWEEN SPEED OF MILKING AND SOMATIC CELL COUNT AND PRODUCTION IN HOLSTEINS

1983 ◽  
Vol 63 (4) ◽  
pp. 781-789 ◽  
Author(s):  
R. K. MOORE ◽  
J. E. MOXLEY ◽  
B. W. KENNEDY ◽  
E. B. BURNSIDE
Keyword(s):  
Somatic Cell ◽  
Cell Count ◽  
Milk Yield ◽  
Somatic Cell Count ◽  
Genetic Correlations ◽  
Heritability Estimate ◽  
Phenotypic Correlations ◽  
Cell Counts ◽  
Holstein Friesian ◽  
The Relationship

Milking speed data were obtained for 2604 Holstein-Friesian cows, identified by sire, in test herds located in Quebec and Ontario. Milk samples were collected from each cow and analyzed for somatic cell count. Completed or projected lactation production records were available for this sample of cows. Two-minute yield and total milking time were adjusted for the effect of milk yield at sampling and the raw cell counts were transformed to the natural log scale. Sire and error variances were obtained by maximum likelihood (ML) methods and used to estimate heritabilities of and correlations between traits. The heritability estimate for the adjusted 2-min. yield, 0.23, was higher than that for the adjusted total milking time (0.13), with the estimates for the two unadjusted measures being intermediate (0.18). The phenotypic correlations between milking speed and somatic cell count were small. However, there were two distinct linear phases to the relationship between the adjusted 2-min yield and cell count. Small but significant phenotypic correlations were observed between unadjusted measures of milking speed and lactation production (0.11–0.22); however, correlations were not significant when adjustments were made for the milk yield at sampling. Genetic correlations between milking speed and somatic cell count were moderate to large and indicated an antagonistic relationship between faster milking speed and cell count. Also, the genetic correlations suggested some antagonism between increasing 2-min yield and lactation production, while the relationship between lactation traits and milking time was small. Key words: Milking speed, somatic cell count, correlations, heritabilities, Holsteins

scholarly journals Effect of somatic cell count on milk fat and protein in different parities and stages of lactation in Holstein cows

2017 ◽  
Vol 110 (1) ◽  
pp. 37
Author(s):  
Arash CHEGINI ◽  
Navid GHAVI HOSSEIN-ZADEH ◽  
Hossein HOSSEINI-MOGHADAM ◽  
Abdol Ahad SHADPARVAR
Keyword(s):  
Somatic Cell ◽  
Cell Count ◽  
Milk Fat ◽  
Fixed Effects ◽  
Somatic Cell Count ◽  
Repeated Measurements ◽  
Somatic Cell Score ◽  
Holstein Cows ◽  
Dry Period ◽  
Protein Percentage

<p>The objective of this study was to investigate the effect of somatic cell score (SCS) on milk fat and protein in different parities and stages of lactation in Iranian Holstein cows. Records between June 2003 and January 2014 from 208,478 cows in lactations one to nine in 845 herds, comprising 2,456,303 monthly test-day (TD) records were used. The MIXED procedure of the SAS software with repeated measurements was used. The fixed effects of the model were herd, year-season of calving, month of TD, weeks of lactation, previous dry period length and somatic cell score (SCS) and covariate was calving age. Lactations were divided into six stages and analyses were performed within each stage. Also, different lactations were analyzed separately. Increase of SCS led to increase of milk fat and protein percentage and the increase of milk fat and protein associated with SCS was higher in early stages of lactation relative to later stages of lactation. Also, increase of milk fat and protein associated with SCS was higher in the first lactation rather than later lactations and decreased with increase of parity.</p>

scholarly journals Evaluation of breeding values of bulls for somatic cell count in milk

2011 ◽  
Vol 27 (3) ◽  
pp. 1059-1066
Author(s):  
M. Radinovic ◽  
S. Trivunovic ◽  
D. Kucevic ◽  
R. Djedovic ◽  
V. Bogdanovic
Keyword(s):  
Mammary Gland ◽  
Somatic Cell ◽  
Cell Count ◽  
Milk Yield ◽  
Milk Fat ◽  
Somatic Cell Count ◽  
Somatic Cells ◽  
High Variability ◽  
Breeding Values ◽  
Selection Of

The incidence of subclinical and clinical mastitis in the mammary gland produces variety of defensive factors were nuclear leukocytes, lymphocytes and macrophages play an important role and they are marked as somatic cells. Somatic cell count depends on the type of pathogen and stage of infection. Increased number of somatic cells in milk occurs as a result of lesions in the mammary gland. Studies have shown that the somatic cells count is genetically predisposed. Although the heritability of this trait is low, using modern methods and the proper selection of work it is possible to achieve some progress. Therefore it is necessary to the selection of bulls for somatic cells, on the basis of somatic cells in milk of daughters. Data on milk yield and somatic cell count in milk of 247 cows Holstein Friesian and Simmental breed from Vojvodina province, were used to analyze the evaluation of breeding values for somatic cells in milk Average values and variability of somatic cells, milk yield, milk fat yield and protein and content of milk fat and protein were determined. The average number of somatic cells was 317 000 per ml of milk, with high variability. Average milk yield of 7 634kg with an average content and yield of milk fat from 3.74% to 285.69 kg and the average protein content and yield of 3.15% and 237.15 kg were determined. Assessment of breeding values was calculated using BLUP model of father, high variability in the assessment of bulls was found. Getting more accurate breeding values is possible using the Animal Model.

Sign in / Sign up

Export Citation Format

Share Document