Bulletin of The Iwate Agricultural Research Center No.4
|Labor-saving Management Technology and Milk Production by the Milking Robot|
|Naoki YAMAGUCHI, Mitsugu YAMATO, Fuminari KIKUCHI, Teruo KAWAMURA and Yukio SEIMIYA|
| The milking robot is technology developed the purpose of cutting down
sharply milking work, which accounted for roughly half of the workload
in managing dairy farm, and of labor-saving on milking related work. It
was our aim to confirm the labor-saving management aspect and clarify the
influence on milk production of the milking robot.
We investigated throughout the period in June 1998 to December 2001, the training of the cows being introduced to the robot, the rate of voluntary visiting to the robot to be milked, the milking frequency, the influence of one-way cow traffic on the behavior of the cows, labor-hours and the nature of daily activities around the robot, and milk production. A herd of 20-25 Holstein cows were studied during the experiment. The cows were fed and managed in a free-stall cowshed that had single group management and delivery of TMR constant. We used a milking robot made by Lely Company that operated continually for 24 hours except for 60 minutes during bulk tank washing time. Furthermore, we used a free stall and a milking parlor (herringbone) as a test contrast, milking twice a day in the morning and the evening. After three weeks, 80% of the cows visited the robot and were milked voluntarily. As time progressed, the training was reduced and the cows increasingly visited the robot voluntarily.
By using one-way cow traffic, the cows were milked more frequently. In our experiment, we spent 75 minutes of labor on daily activities around the robot. The milking related work under robotic milking was cut by 1/2 as compared with parlor milking. Through maintaining milk compositions by using a milking robot that the cows frequently visited voluntarily, and constantly feeding TMR, daily milk yield increased by 11-15%.
|Identification of Deletion Mutation in Myostatin Gene Associated with Double muscling in Japanese Shorthorn Cattle Breed and Its Effect on Meat Productive Traits|
|Toshiyuki SUZUKI, Kenji OHTAWARA, Yoshikazu SUGIMOTO, Syuichi TANAKA, Shigeki KOMATSU and Yoshisato YOSHIKAWA|
| Muscular hypertrophy in cattle (double muscling, DM) has been selected
as a superior phenotype in meat production in Europe, on the other hand,
DM had not been found on and after the 1990s since it referred as pig-hips
had been excluded due to its association with lower meat quality in Japan.
We found a Japanese shorthorn calf exhibiting DM in Iwate in 1998. In order
to control DM in the population we analyzed the causative gene, myostatin,
in the calf, and identified 11-bp deletion of the gene which is widely
distributed among European cattle population.
Using a DNA test detecting the 11-bp deletion, we found that 30 sires of which 247 of Japanese shorthorn heterozygously harbored the deletion mutation. We further surveyed the deletion mutation in 61 offspring of the heterozygous sires, and found one mutant allele in 32 offspring and two mutant alleles in four, the latter which were diagnosed to be DM. In addition, we investigated meat productive traits in three DM cattle fattened. The three DM cattle were not superior in growth competence to six normal cattle, but increased in muscle mass of approximately 20%.
The grading results of all DM cattle were A-1, indicating that DM cattle may not be recommended to beef farmers. However, a DM phenotype could become precious genetic resource for production of lean beef in the near future.