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Volume 71, Issue 10
Displaying 1-10 of 10 articles from this issue
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Applications of DNA Information to Animal Breeding Programs with a Special Reference to Dairy CattleKenji TOGASHI2000 Volume 71 Issue 10 Pages 447-458
Published: October 25, 2000
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSThe identification of candidate genes or genetic markers by DNA-based technology offers a great potential to speed up the genetic improvement of animal productivity. The use of DNA information is expected to accelerate genetic progress through 1) increasing the accuracy of selection, 2) reducing the generation interval, 3) increasing selection differentials, and 4) efficient transfer of favorable genes from a donor to a recipient population. When desirable QTLs (Quantitative Trait Loci) are identified, direct genotypic selection on QTL is possible and effective. Even if QTL information is not available, genetic markers linked to the QTL can be utilized for marker-assisted selection (MAS). Linkage disequilibrium between marker and QTL alleles within families is required for MAS in animal population, particularly in dairy cattle. Genetic markers can be used for within-family selection such as top down and bottom up programs in dairy cattle, which enables the pre-selection of young bulls for progeny testing. The use of advanced reproductive technologies is a prerequisite to realize the potential genetic gain. Direct selection on QTL or marker-assisted selection offers the greatest advantage when the heritability of the trait is low. The importance of genetic markers decreases when phenotypic records or estimated breeding values are available. However, genetic markers or candidate genes have potential applications for improving sex-limited traits or traits not directly measurable such as carcass traits. Marker-assisted introgression using backcrossing is an alternative approach to incorporate the desired alleles. The efficiency of the introgression depends on the genetic value of the final product of the crossbred compared to the recipient population under continued selection. In this respect, some revised steps to increase production level in crossbreds are reviewed. Both position and effect of QTL have to be measured with prediction error variance so that its influence on selection response can be clearly determined. Thus, breeding system incorporating DNA information can be realized with prediction error variances even if QTL are not identified. DNA information would provide many clues not only to productivity but reproduction or disease resistance. DNA information would be a vital clue to improvement for lifetime/overall productivity influenced by productivity, reproduction and disease resistance.View full abstractDownload PDF (1257K) -
Report on Symposium in the 97th meeting of japanese Society of Animal ScienceT Manda, Y Mizokawa, K Kaya, M Kitagawa, A Suzuki, H Yano, N Manabe, T ...2000 Volume 71 Issue 10 Pages 459-469
Published: October 25, 2000
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSDownload PDF (1409K) -
Hideyuki MANNEN, Junichi KAWASAKI, Takafumi ISHIDA, Fumio MUKAI, Soich ...2000 Volume 71 Issue 10 Pages 470-474
Published: October 25, 2000
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSIn our previous study, two major mtDNA types were observed in Japanese Black cattle; one has been detected exclusively in Japanese samples (Japanese Black type), whereas the second is comprised of samples that show sequences and patterns of variability similar to those found in European samples (European type). This article describes mitochondrial DNA displacement loop polymorphisms and their frequencies in three representative Japanese Black cattle populations. PCR-SSCP method was applied to analyze the mtDNA polymorphisms. Differences of the genetic frequencies between populations were observed in European type mitochondrial DNA. The results suggested that the grading with European breeds in Meiji era retains genetic influence on modern Japanese Black cattle.View full abstractDownload PDF (1039K) -
Ken-ichi HORIGUCHI, Toshiyoshi TAKAHASHI2000 Volume 71 Issue 10 Pages 475-482
Published: October 25, 2000
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSTwo experiments were undertaken to determine the effect of ruminal dosing of mechanical stimulating brush (RF) for the mucosa in the rumen on the rumination time and rumen fermentation status. The rumination behavior under field flock in experiment 1 (8 heads) and rumination behavior and rumen fermentation status under individual feeding in experiment 2 (8 heads) were investigated under high concentrate diets (organic cell wall contents: 27.5% DM) using Holstein steers (16 heads). The experimental animals were orally administered the RF (three RF per head) at 12 month of age in experiment 1 and 8 month of age in experiment 2 as a RF treatment (4 heads), and the non-administration was made as control (4 heads) in both experiments. Grass hay was fed to the animals (0.2kg/head) at 19 month of age, and was not fed later in experiment 1 and concentrate was given ad libitum in. Concentrate was fed to the animals as a sole diet in experiment 2; and was fed to suffice 1.0kg daily gain. The observation of rumination behavior was carried out at 14 month of age (average weight 513kg), 17 month of age (616kg) and 20 month of age (696kg) in experiment 1. The observation of rumination behavior and the investigation of rumen fermentation status were carried out at 18 month of age (average weight 696kg) in experiment 2. In experiment 1, there was no statistical difference (P>0.05) for feed intake between the RF treatment and the control. The rumination time per day for the animals in the RF treatment was longer (P<0.05) than that in the control group. In experiment 2, the feed intake per day was greater (P<0.05) for the RF group than for the control. The rumination time per day and per DM intake for the animals in RF treatment was longer (P<0.05) than that in control group. The ruminal VFA concentration was greater for the RF group than the control for 6 to 12h post morning feeding. With it, the ruminal pH for the animals in RF treatment tended to be lower than that in control group, but the pH value before morning feeding did not differ statistically (P>0.05) between the RF treatment and the control. The ratio of acetic acid to propionic acid for RF group was lower than that in control group. From the above result, it is supposed that RF affected the mucosa in the rumen as a physical stimulus under high concentrate diets, and it is suggested that there was the possibility of lengthening mastication time of rumination per day by the induction of the regurgitation of a bolus.View full abstractDownload PDF (1320K) -
Atsushi HIRAO, Shoei SUGITA, Kunio SUGAHARA2000 Volume 71 Issue 10 Pages 483-490
Published: October 25, 2000
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSIn order to clarify olfactory system of birds, the efferent and afferent connections of chicken olfactory bulb were investigated using with biocytin and horseradish peroxidase (HRP) methods. From the results of biocytin method, the efferent pathways of chicken olfactory bulb were classified into route 1-3.Route 1 projected to the ipsilateral hyperstriatum accessorium (HA), and hippocampus (Hp). Route 2 had the projections to ipsilateral hyperstriatum intercalatum supremum, hyperstriatum ventrale (HV), neostriatum (N), and nucleus basalis (Bas). Route 3 projected to the bilateral lobus parolfactorius, tuberculum olfactorium tractus fronto-archistriaticus, paleostriatum augmentatum, archistriatum anterior, cortex piriformis, area temporo-parieto-occipitalis, nucleus taeniae, contralateral HA, Hp, HV, N, and Bas. From the results of HRP method, the chicken olfactory bulb received the projections from nucleus septalis medialis, nucleus septalis lateralis, and Hp. In addition, it was appeared that the chicken olfactory bulb has the reciprocal connection with Hp.View full abstractDownload PDF (1192K) -
Tetsuya MASUDA, Hitoshi Reginald YAMASAKI, Kazui SUZUKI, Toshiki MORIC ...2000 Volume 71 Issue 10 Pages 491-497
Published: October 25, 2000
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSIn cottage cheese manufacture, spongy curd formation in the bottom of cheese vat has been reported by several researchers. It was said that this spongy curd was caused by an uneven distribution of starter bacteria resulting from their agglutination, and this phenomenon has been a big problem in the processing of fermented milk products. Although the participation of immunoglobulins in milk in this bacterial agglutination has been shown, the mechanism of this agglutination remained unknown. So, in this study, the agglutination of test strains of Lactococcus lactic subsp. cremoris in milk was confirmed and the mechanism of this agglutination was elucidated. As the results, it was found that IgM bound to the bacterial cells in all the test eleven strains. The immunochemical technique clearly showed that the common specific five polypeptides (M. W.; 22-52kDa) existed in the bacterial cells of test strains strongly agglutinated by IgM. On the other hand, in case of test strains weakly agglutinated by IgM, it was thought that either these polypeptides did not completely exist in the bacterial cells or if even present, their strength of binding with IgM was weak. The close relation between their agglutination property by IgM and their strength of binding with IgM was confirmed. It was suggested that the agglutination by IgM originated from the connection of these polypeptides with IgM.View full abstractDownload PDF (2672K) -
Masatoshi IZUMIMOTO, Mizuhou DOI2000 Volume 71 Issue 10 Pages 498-504
Published: October 25, 2000
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSFor the measurement of meat tenderness, Warner-Bratzler shear force value (SFV) device has been widely used, by which only SFVmax can be measured. Therefore, SFV profile was measured and compared during whole shearing stroke for intact meat and meat products. SFV profile was obviously different among meat and meat products. Their characteristics were normalized against SFV and stroke resulting in clear comparison between the profiles. SFV max of almost intact meat was found at final shearing point of stroke and that of sausage was found at the center of stroke. Muscle fiber toughness maximum (MFT max ) of intact meat, sausage and ham, could be considered as SFV at the center of stroke. SFV max was lineally related with the diameter of sausage sample and with the sample raised to the power of 1.5 diameter for ham and intact meat, concurring with the theoretical prediction. SFV max /MFT max value and the deviation were lower in order of sausage, ham and intact meat. It was suggested to depend on the properties of artificial weakening for connective tissue in each sample.View full abstractDownload PDF (580K) -
Peishi YAN, Sadaki YAMAMOTO2000 Volume 71 Issue 10 Pages 505-509
Published: October 25, 2000
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSFor the management of thermal environment, the significance of the relationship between thermoregulatory responses, sensible and latent heat loss were studied. Four female Landrace pigs were exposed to environmental temperatures (Te) of 10, 15, 20, 25, 30 and 35°C daily for 8 hours. Sensible heat loss (sHL), total evaporative heat loss (eHL), rectal temperature (Tr), mean skin temperature (mTs), and respiration rate (RR) were measured. At Te 10-35°C, mTs increased by 0.47 for every 1°C. An increase in Tr, RR and eHL was found in Te of 31°C or more (P<0.01). With an increase in Te, RR increased by 13/min. for every O.1°C rise in Tr, sHL decreased by 1.2kJ/kg0.75h for every 1°C rise in mTs, and eHL increased by O.04kJ/kg0.75 h for every 1/min rise in RR. Therefore, the changes of Tr, mTs, and RR were useful information which showed concrete effect from the complex thermal factor for nvironmental management.View full abstractDownload PDF (387K) -
Peishi YAN2000 Volume 71 Issue 10 Pages 510-515
Published: October 25, 2000
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSIn order to obtain a better understanding of the characteristic of thermoregulation in piglets, variations in thermoregulatory responses were studied in four female piglets in a constant environmental temperature of 25°C where they received one of the three levels of feed at TDN level of 0, 60, 96g/kg0.75 d. The daily feed was distributed in equal quantity at 0800h and 2000h to standardize heat production (HP) from feed ingestion. The influence of HP on rectal temperature (Tr), surface temperature (Ts) and respiration rate (RR) was clearly observed. The Tr and RR were greater during the 1300-1700h than during the 0100-0500h, and the difference of Tr was 0.3-0.8°C. The mean surface temperature (mTs) and Ts of tip sites such as ear tip, snout and pastern were greater during the 0100-0500h than during the 1300-1700h, and the difference of Ts of tip sites was 4-5°C. The contrast in the daily pattern of RR and mTs was conspicuous features. This may indicate that the increased sensible heat loss by mTs was to supplement heat balance with the decrease in evaporative heat loss of respiration during 0100-0500h.View full abstractDownload PDF (446K) -
Akemi YAMAMOTO, Chieko FURUKAWA, Eiji TAKAHASHI, Mitsuhiro OKADA, Shu ...2000 Volume 71 Issue 10 Pages 516-519
Published: October 25, 2000
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSThe feed value of the inorganic phosphorus in the incinerated broiler and laying hens manure was estimated by the chemical analysis of them and the growing performance of chicks. Calcium and phosphorus concentrations of incinerated poultry manure obtained from two farms in broiler and laying hens were determined to be on the average 12.3% and 5.47%, and 7.70% and 3.55%, respectively. The ratios of calcium: phosphorus of incinerated broiler and laying hens manure were approximately 2.0:1, which was almost same for calcium: phosphorus of calcium and non-phytate phosphorus requirements for swine and broiler. No significant differences were observed in feed intake, body weight gain and feed conversion ratio in chicks fed the diet contained 1.13% of dicalcium phosphorus or 3.50% of incinerated laying hens manure as an inorganic phosphorus source for 1 week. These results suggested that the incinerated poultry manure could be utilized successfully as an inorganic phosphorus in feed sources.View full abstractDownload PDF (300K)
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