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Volume 83 (2012)
- Issue 4 Pages 335-
- Issue 3 Pages 271-
- Issue 2 Pages 117-
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Volume 83, Issue 1
Displaying 1-7 of 7 articles from this issue
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Review Article
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Yoshitaka NAGAMINE2012 Volume 83 Issue 1 Pages 1-8
Published: February 25, 2012
Released on J-STAGE: August 25, 2012
JOURNAL FREE ACCESSRecently many reports for the application of genomic selection in animal breeding, especially for dairy cattle, have been published. Accumulating effects of large number of genetic markers relating to phenotypic value and using them for the selection was the basic idea (Meuwissen et al. 2001) of the genomic selection. However, significant Single Nucleotide Polymorphism (SNP) markers from large data sets of human population could explain only a small proportion of genetic variance for a very heritable trait, height, and the remaining is known as “missing heritability”. There are several ways to apply non-significant SNPs to increase the accuracy in selection. Using genomic relationship (G) matrix instead of Henderson’s additive genetic relationship matrix, for example, can increase accuracy in estimation of breeding values with considering the Mendelian sampling terms. Mathematical models using both G matrix and significant SNPs might be useful in real livestock selection. There are still many considerable challenges we need to clarify the influence of genomic selection before eliminating progeny testing in animal breeding.View full abstractDownload PDF (753K)
Original Articles
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Koichi HAGIYA, Takefumi OSAWA, Yutaka MASUDA, Mitsuyoshi SUZUKI, Takes ...2012 Volume 83 Issue 1 Pages 9-19
Published: February 25, 2012
Released on J-STAGE: August 25, 2012
JOURNAL FREE ACCESSGenetic correlations between herd life and production/type traits over time were investigated using multiple trait models (MTLM) and multiple trait random regression models (MTRRM). Data of first lactation records (milk, fat, protein and milking persistency), somatic cell score and 16 type traits were collected from 377,195 cows born between 1990 and 2002 with their 772,158 pedigree records. Various fixed effects were considered for production traits (herd-year, calving month, calving age), type traits (herd-classifier-classified day, age at classification, lactation stage) and herd life (herd-year, calving age) in the statistical models. Random additive genetic and residual effects were included in the models for all traits. Three subsets of data based on cow’s birth year (1990-1995, 1996-2000, 2001-2002) were used for MTLM. Third order Legendre polynomials were used for additive genetic effects in MTRRM. Genetic correlations between herd life and other traits were different in birth year but those estimates from MTLM and MTRRM were similar. For cows born in the 1990s, genetic correlations between herd life and production traits and between herd life and udder support gradually decreased over the years. Genetic correlations between herd life and angularity were close to zero in the early 1990s ; however, they decreased in the late 1990s and reached to —0.23 in 2001 for MTLM. Genetic correlations between herd life and somatic cell score were negative for 13 years. Results suggest that genetic parameters for herd life evaluation should be updated with recent data.View full abstractDownload PDF (1133K) -
Yoshinobu NAKAHASHI, Yutaka MASUDA, Keigo KUCHIDA2012 Volume 83 Issue 1 Pages 21-28
Published: February 25, 2012
Released on J-STAGE: August 25, 2012
JOURNAL FREE ACCESSIn Japan, crossbreds (F1) of Holstein cow sired by Japanese Black (JB) cattle have been an important source of beef products, occupying about 25% of the number of graded beef carcasses. However, to date, a unique genetic evaluation of F1 has not been conducted. Thus, dairy farmers have to depend on JB sires by breeding values predicted from JB data, but interactions could exist between sire and breed of dam. The objective of this study was to explore the need for a unique evaluation of F1 by investigating such interactions. These were evaluated as genetic correlation (rg) using a 2-trait sire model which regarded the identical traits from each breed (JB and F1) as different. Six grading traits, such as beef marbling standard (BMS), were analyzed. A high rg between JB and F1 was estimated for BMS (0.91). Subsequently, Spearman’s correlation coefficient of the expected progeny difference (EPD) of JB sires predicted from JB and F1 population was calculated and showed a high value (0.96), indicating that there was a little interaction. With similar results for other traits, EPD predicted from JB data would be applicable for F1 production.View full abstractDownload PDF (563K) -
Yoshinobu NAKAHASHI, Tetsuro YUSA, Yutaka MASUDA, Satoshi HIDAKA, Keig ...2012 Volume 83 Issue 1 Pages 29-34
Published: February 25, 2012
Released on J-STAGE: August 25, 2012
JOURNAL FREE ACCESSThe objective of this study was to estimate the genetic parameters of fatty acid composition in the rib eye of Japanese Black cattle. Genetic relationships between fatty acids and image analysis traits of marbling were also investigated to clarify the response to the improvement of fatty acids composition on the marbling characteristics. Carcass data were obtained from Japanese Black cattle (n = 4,615) shipped to a meat processing plant in Hokkaido, Japan. Fat tissues were sampled from the rib eye of each carcass, and the fatty acid composition was analyzed using gas chromatography. Image analysis traits such as marbling percent (MP), coarseness index of marbling (CIM) and fineness index of marbling (FIM) in the rib eye were calculated. Using single/multiple traits animal models, genetic analyses were conducted to estimate heritabilities of all the traits and genetic correlations of the major fatty acids percentages with the image analysis traits. The estimated heritabilities of the fatty acids ranged from 0.67 to 0.82. The genetic correlation coefficients of Oleic acid (C18 : 1) with BMS and MP were positive (0.24 and 0.16, respectively) showing a favorable relationship in which the increased MP resulted in the improvement of C18 : 1 percent. On the other hand, undesirable correlation coefficients of C18 : 1 with CIM and FIM were estimated (0.32 and —0.35, respectively) and results suggested that the improvement of C18 : 1 percent increases the coarseness of marbling flecks in the rib eye.View full abstractDownload PDF (503K) -
Mizuna OGINO, Akihiro MATSUURA, Atusi YAMAZAKI, Mami IRIMAJIRI, Shiro ...2012 Volume 83 Issue 1 Pages 35-46
Published: February 25, 2012
Released on J-STAGE: August 25, 2012
JOURNAL FREE ACCESSWe investigated secretory rhythms of the plasma growth hormone (GH) and prolactin (PRL) in cattle by spectral analysis using the maximum entropy method (MEM). MEM is considered more useful than the fast Fourier transform (FFT) and Cosinor methods because MEM can yield results of high spectral resolution, with high precision and analytical capability from short-period data. However, few challenges are faced in performing spectral analysis by MEM with regard to sampling interval and lag. Cyclic rhythms (hours) of hormone secretion in cattle determined by MEM under different conditions of sampling interval and lag within different seasons were compared. For hormones such as GH and PRL that exhibit both short-period (ultradian) and long-period (circadian) secretory rhythms, MEM was found to be the best method for sampling by short-time interval, for example, 15 min and in addition, increasing the lag number made the detection of both short- and long- period rhythms possible. However, the analysis of 30-min interval sampling data yielded a result similar to that of 15-min interval data. Therefore, for the investigation of secretory pattern with longer than 15-h rhythm, consecutive sampling of longer than 30 h is needed.View full abstractDownload PDF (898K) -
Yuko SHINGU, Mitsuo MORI, Hiroki NAKATSUJI, Seiji KONDO, Kazuhiro UMEM ...2012 Volume 83 Issue 1 Pages 47-56
Published: February 25, 2012
Released on J-STAGE: August 25, 2012
JOURNAL FREE ACCESSHeart rate (HR) and grazing activity of lactating cows were measured to assess the energy expenditure (EE) associated with grazing on an inclined slope. In experiment 1, the HR and movements of lactating Holstein cows grazing on an inclined slope were recorded using an HR monitor and a global positioning system (GPS). These data were used in conjunction with altitude to calculate relative heart rate (RHR : HR during grazing/HR during rest while standing) per moving inclination during grazing. In experiment 2, the moving inclination of lactating Holstein cows during grazing was measured using a GPS receiver on an inclined pasture (11.8°) and the daily EE associated with grazing was calculated with the RHR values obtained in experiment 1. In experiment 1, the HR associated during grazing and resting while standing were 92.9 and 88.0 beats/min, respectively. The RHR associated during grazing was higher than during resting while standing (P < 0.05). Also, the RHR of cattle ascending inclinations greater than 8° (1.15) during grazing were higher than those of cattle ascending inclinations of 0° to 2° (1.09) (P < 0.01). No difference was observed between the RHR of cattle descending inclinations of 0° to 2° and the RHR of cattle descending inclinations greater than 2°. In experiment 2, the time budget for grazing per day was 500.2 to 584.0 min, and the percentage of cattle ascending more than 8° during grazing was 12.9 to 16.4%. The EE associated with grazing per day ranged between 306.2 and 346.3 kJ/BW0.75, which was similar to the estimated EE in cows grazing on a level pasture. The inclination of a pasture therefore seemed to have no effect on the EE associated with grazing, likely because the ascending inclination of lactating cows during grazing was less than the inclination angle of the pasture as a whole. However, it suggested that the EE associated with grazing estimated from the percentage of cattle ascending or descending and RHR was overestimated.View full abstractDownload PDF (870K)
Technical Reports
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Miho KOBAYASHI, Kazuyoshi SUZUKI, Susumu MIYAMOTO, Koichi NISHIMURA, M ...2012 Volume 83 Issue 1 Pages 57-64
Published: February 25, 2012
Released on J-STAGE: August 25, 2012
JOURNAL FREE ACCESSThe accident at the Fukushima Daiichi Nuclear Power Plant run by the Tokyo Electric Power Company (TEPCO) occurred on March 11, 2011, leading to radionuclides leaks in the external environment. In Nasu research center of NILGS, winter grazing trials of dairy cows were conducted. We studied the contamination of radionuclides in milk of grazing cows on the contaminated pasture and cows fed in indoor cowhouse. Six Holstein dairy cows had grazed on Italian ryegrass-dominant pasture and fed with indoor stored feed before the Fukushima accident until April 3, 2011. The other dairy cows in indoor cowhouse were fed stored total mixed ration (TMR) at all seasons. The concentration of Iodine-131 and total of radiocesium (Cesium-134+cesium-137) in milk of grazing cows on April 3 were 1,178.9 ± 2.6Bq/L and 1,154.9 ± 1.56Bq/L, respectively, while, the radioactive contamination of milk obtained from indoor cowhouse remained in low level during April. On April 4, 6 cows stopped grazing and fed TMR. The concentration of radioiodine and radiocesium in milk declined below the provisional regulation value after 3 days and 7 days, respectively.View full abstractDownload PDF (744K)
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