Estimates of genetic parameters for milkability from automatic milking

Gäde, S.; Stamer, E.; Junge, Wolfgang; Kalm, E.

doi:10.1016/j.livsci.2006.04.003

Cited by 26 publications

(45 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Lactation heritabilities of 0.46, 0.44 and 0.41 for lactations 1, 2 and 3, respectively, were derived when 10 equally spaced test-days per lactation were assumed. These heritabilities agreed with estimates from other studies, where models with repeated observations per cow were applied (Gä de et al, 2006;Norberg and Rasmussen, 2007).…”

Section: Resultssupporting

confidence: 89%

“…In our study, data were from a larger time span (9 years v. 3 years) and, therefore, besides using a different model, a better structure of the data might explain the higher estimates. The heritability of automatically recorded milk flow rate reported by Gä de et al (2006) and Norberg and Rasmussen (2007) was, respectively, 0.55 and 0.39. In Ilahi and Kadarmideen (2004), the heritability of measured AFR for Brown Swiss and Simmental was 0.46 and 0.48, respectively.…”

Section: Resultsmentioning

confidence: 90%

See 1 more Smart Citation

Genetic parameters for milkability from the first three lactations in Fleckvieh cows

Dodenhoff

Emmerling

2009

Animal

View full text Add to dashboard Cite

Test-day records for average flow rate (AFR) from the routine dairy recording from Bavarian Fleckvieh cows were analysed. Two data sets with observations on approximately 20 000 cows each were sampled from the total data set. For the estimation of variance parameters, a two-step approach was applied. In a first step multiple-trait restricted maximum likelihood (REML) analyses were carried out. For each of the first three lactations, six time periods with up to 33 days were defined. An algorithm for iterative summing of expanded part matrices was applied in order to combine the estimates. In a second step covariance functions (CF) for additive-genetic variances and non-genetic animal variances were derived using second-order Legendre polynomials plus an exponential term. Estimates of test-day heritability for AFR ranged from 0.21 to 0.40, and were largest in lactation 1. For lactations 1 and 3, heritabilities decreased considerably towards the end of lactation. Genetic correlation estimates within lactation decreased as the distance between days in milk (DIM) increased. Genetic correlations between corresponding DIM in the three lactations were generally large, ranging from 0.80 to 0.99. The largest estimates were found between DIM from lactations 2 and 3. Results from this study suggest that including AFR data from second and third lactations in genetic evaluation systems could the improve accuracy of genetic selection.

show abstract

Section: Resultssupporting

confidence: 89%

Section: Resultsmentioning

confidence: 90%

Genetic parameters for milkability from the first three lactations in Fleckvieh cows

Dodenhoff

Emmerling

2009

Animal

View full text Add to dashboard Cite

show abstract

“…Selection for good milkability thus seems to have promise. In a previous study (Gä de et al, 2006), the heritabilities estimated based on daily values for serial milkability from an automatic milking system were h 2 5 0.55 for average milk flow, h 2 5 0.55 for maximum milk flow and h 2 5 0.39 for milking time, thus being similar to the respective estimates from the present study. In contrast, estimates for serially recorded milking speed from Karacaö ren et al (2006) using daily test-day random regression methodology were considerably lower varying from h 2 5 0.003 to h 2 5 0.098 for day 1 to day 305 of lactation.…”

Section: Discussionsupporting

confidence: 88%

“…The fixed effects included in the models 1 and 2 were chosen in reference to a previous study (Gä de et al, 2006) and because they were significant in the analysis of variance. For the SCS, model 2 was applied with 165 herd test-days (j 5 1 to 165), 10 009 additive genetic effect levels and 5909 permanent environmental effect levels.…”

Section: Discussionmentioning

confidence: 99%

“…Therefore, an uninterrupted milkability test over the course of lactation is possible, meaning that there is information concerning every day and every parity. In previous studies, heritabilities were estimated for milkability traits based on serial data ranging from h 2 5 0.003 to h 2 5 0.55 (Zwald et al, 2005;Gä de et al, 2006;Karacaö ren et al, 2006).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Genetic parameters for serial, automatically recorded milkability and its relationship to udder health in dairy cattle

Gäde

Stamer

Bennewitz

et al. 2007

Animal

Self Cite

View full text Add to dashboard Cite

Serial measurements of three milkability traits from two commercial dairy farms in Germany were used to estimate heritabilities and breeding values (BVs). Overall, 6352 cows in first, second and third lactations supplied 2 188 810 records based on daily values recorded from 1998 to 2003. Only the records between day 8 and day 305 after calving were considered. The estimated genetic correlations between different parities within the three milkability traits ranged from r g 5 0.88 to 0.98, i.e. they were sufficiently high to warrant a repeatability model. The resulting estimated heritability coefficients were h 2 5 0.42 for average milk flow, h 2 5 0.56 for maximum milk flow and h 2 5 0.38 for milking time. We analysed the genetic correlation between milkability and somatic cell score (SCS) and between milkability and the liability to mastitis, respectively, as the optimum milk flow for udder health is not well defined. There were 66 146 records with information on somatic cell count. Furthermore, 23 488 days of medical treatment for udder diseases were available, resulting in 2 600 302 days of observation in total. Heritabilities for the liability to mastitis, estimated with a test-day threshold model, were h 2 5 0.19 and h 2 5 0.13, depending on the data-recording period (first 50 days of lactation and first 305 days of lactation, respectively). With respect to the relationship between milkability and udder health, the results indicated a slight and linear correlation insofar as one can assume: the higher the milk flow, the worse the udder health. For this reason, bulls and cows with high BVs for milk flow should be excluded from breeding to avoid a deterioration of udder health. The establishment of a special data-recording scheme for functional traits such as milkability and mastitis on commercial dairy farms may be possible according to these results.

show abstract

Genetic parameter estimates for milkability traits and their relationship with somatic cell score in South African Holstein cattle

Tshilate

Bhebhe

Dube

et al. 2020

Trop Anim Health Prod

View full text Add to dashboard Cite

Estimates of genetic parameters for milkability from automatic milking

Cited by 26 publications

References 11 publications

Genetic parameters for milkability from the first three lactations in Fleckvieh cows

Genetic parameters for milkability from the first three lactations in Fleckvieh cows

Genetic parameters for serial, automatically recorded milkability and its relationship to udder health in dairy cattle

Genetic parameter estimates for milkability traits and their relationship with somatic cell score in South African Holstein cattle

Contact Info

Product

Resources

About