Although the number of dairy farms is decreasing, that of large farms is increasing in Japan. Milk production in Japanese dairy cows has increased from 62 kg/year to 88 kg/year over the last 2 decades. However, Japanese dairy cows are experiencing a sustained decline in reproductive performance, calving intervals, and days open; further, the number of inseminations required for conception have ...

Dairy cattle are inseminated and pregnancy is established during lactation. Therefore, lactation and the reestablishment of pregnancy must overlap. Unfortunately, recent changes in the genetics, productivity, and management of dairy cows have led to a decline in reproductive efficiency. Reproductive decline in dairy cows began in the mid-1980’s and may be continuing on modern dairy farms (Lucy,...

Little is known about rest and sleep in dairy cows, but it has been shown in other species that the total amount of sleep, duration of sleep bouts and distribution of sleep over 24 hours differ depending on health status, age, pregnancy and lactation. Sleep recordings conducted on cows with surgically implanted electrodes have shown that they sleep four hours per 24-hour period. In this thesis,...

This research is focused on the evaluation of milk flow traits of Slovak Simmental dairy cows, using electronic mobile milk flow meters Lactocorders. All measurements were carried out on a farms located in the western Slovakia. We evaluated a total amount of 124 Simmental dairy cows. The Main group of Slovak Simmental dairy cows was divided according to parity and lactation stage respectively, ...

Dairy cattle are inseminated and pregnancy is established during lactation. Therefore, lactation and the reestablishment of pregnancy must overlap. Unfortunately, recent changes in the genetics, productivity, and management of dairy cows have led to a decline in reproductive efficiency. Reproductive decline in dairy cows began in the mid-1980’s and may be continuing on modern dairy farms (Lucy,...

Background: Metabolic profiles have been used in efforts to predict pre parturient problems and fertility, to diagnose metabolic diseases, and to assess nutritional status in dairy cows. These profiles may help to confirm the diagnosis of sub clinical diseases, to be aware of possible causes of infertility in the herds, or to monitor improvement in herd animals. OBJECTIVES: This study investiga...

The number of dairy cows without access to pasture or sunlight is increasing; therefore, the content of vitamin D in dairy products is decreasing. Ultimately, declining vitamin D levels in dairy products will mean that dairy products are a negligible source of natural vitamin D for humans. We tested the ability of a specially designed UVB lamp to enhance the vitamin D3 content in milk from dair...

The present study has been conducted to evaluate the effect of intramuscular administration of vitamin A during dry period in pregnant dairy cows which have already received it in their daily ration on vitamin A status of neonatal calves.Single intramuscular injection of 2000000 IU vitamin A was carried in 10 dairy cows at 7 months of pregnancy (group 1) and in another 10 dairy cows at 8 months...

Adipose tissue has a central role in the regulation of metabolism in dairy cows, and many proteins expressed in this tissue are involved in metabolic responses to stress (Peinado et al., 2012) [1]. Environmental heat stress is one of the main stressors limiting production in dairy cattle (Fuquay, 1981; West, 2003) [2], [3], and there is a complex interaction between heat stress and the transiti...