Days in milk at first AI in dairy cows; its effect on subsequent reproductive performance and some factors influencing it.

The aim of the present study was to show the distribution of cows by days in milk (DIM) at first AI, effect of DIM at first AI on reproductive performance and some factors influencing DIM at first AI. A total of 767 Holstein Frisian cows that calved from January 2004 to December 2007 in 14 dairy herds were used. The first AI conception rate (FAICR) was 34.

Reproductive performance of repeat breeders in dairy herds.

The objectives were to characterize repeat breeding in dairy cows, including reproductive performance and risk factors. Data from 613 Holstein Friesian cows in nine dairy herds across Japan were enrolled. A repeat breeder was defined as a cow that did not become pregnant after three inseminations, despite no clinically detectable reproductive disorders.

Prevalence of endometritis during the postpartum period and its impact on subsequent reproductive performance in two Japanese dairy herds.

The objectives of this study were to ascertain the prevalence of different degrees of endometritis during different periods postpartum, to define 'clinically relevant endometritis', to determine its impact on subsequent reproductive performance, and to determine some risk factors for the incidence of clinically relevant endometritis in dairy cows. Holstein Friesian cows (n=135) from two commercial dairy herds were examined vaginoscopically and by per rectal palpation of genital organs for the first time between 15 and 60d postpartum. Cows with any proportion of pus in the cervico-vaginal discharge were defined as having endometritis and were classified into mild, mucopurulent, or purulent endometritis or postpuerperal metritis.

Stress tensor analysis of the protein quake of photoactive yellow protein.

Immediately after photon absorption, the photoenergy is converted to local stress energy via the ultrafast photoisomerization reaction of the p-coumaric acid (pCA) chromophore in a small water-soluble blue light receptor, photoactive yellow protein (PYP), derived from the halophilic bacterium, Halorhodospira halophila. A series of conformational changes are then induced, which are intimately related with the relaxation process on the energy landscape of PYP. In order to understand the signaling function of PYP in atomic detail, the characterization of the physical mechanism of the protein quake of PYP is important, as is the atomic description of the series of conformational changes associated with the photocycle.