Ovarian follicular waves and secretion of follicle-stimulating hormone after administration of GnRH at estrus

An experiment was conducted to examine the effects of GnRH on the secretion of FSH, LH, estradiol, and progesterone in serum and changes in ovarian structures. Dairy cows were assigned randomly to receive either 100 μg of GnRH or saline 12 hr after estrus (day 0) was detected. Blood was collected daily to assess changes in serum estradiol and progesterone and every 12 min for 8 hr on days 8 and 15 after estrus to assess concentrations of FSH and LH. Diameter and number of follicles were determined daily by real-time ultrasonography. Two patterns of follicular development were observed. The day of peak diameter of each dominant follicle (three or four per cycle) was synchronous with increases in estradiol in serum. The dominant follicle grew at a faster rate in all GnRH-treated cows. We concluded that administering GnRH at estrus increased the pulse frequency of FSH on days 8 and 15 of the cycle, altered follicular dynamics of dominant follicles of the subsequent estrous cycle, and tended to increase concentrations of progesterone in serum of cows

Concentration of anti-Müllerian hormone in dairy heifers is positively associated with productive herd life

Reliable biomarkers predictive of productive herd life (time in herd after birth of first calf) have heretofore not been discovered in dairy cattle. However, circulating concentrations of anti-Müllerian hormone (AMH) are positively associated with number of follicles or antral follicle count (AFC), ovarian function, and fertility, and approximately 25% of cows have a relatively low AFC and low AMH concentrations. The present study tested the hypothesis that heifers with the lowest AMH concentrations have suboptimal fertility and are removed from a herd for poor reproductive performance at a greater rate, and therefore have a shorter productive herd life compared with age-matched herdmates with higher AMH. To test this hypothesis, 11- to 15-mo-old Holstein heifers (n=281) were subjected to a single measurement of AMH. All heifers not removed from the herd had the opportunity to complete 2 lactations and start their third lactation after calving. During this time, performance and health parameters for each individual were recorded daily by herd managers. Results showed that the quartile of heifers with the lowest AMH concentration also had, on average, a shorter productive herd life (by 196 d), a reduced survival rate after birth of the first calf, the lowest level of milk production (first lactation), the lowest total percentage of cows pregnant (across all lactations), the highest culling rates (first and second lactations and overall), and the highest culling rate for poor reproduction (first lactation) compared with age-matched herdmates with higher AMH. We concluded that a single determination of AMH concentration in young adult dairy heifers may be a simple diagnostic method to predict herd longevity, and AMH may be a useful phenotypic marker to improve longevity of dairy cows

Global Search for New Physics with 2.0/fb at CDF

Data collected in Run II of the Fermilab Tevatron are searched for indications of new electroweak-scale physics. Rather than focusing on particular new physics scenarios, CDF data are analyzed for discrepancies with the standard model prediction. A model-independent approach (Vista) considers gross features of the data, and is sensitive to new large cross-section physics. Further sensitivity to new physics is provided by two additional algorithms: a Bump Hunter searches invariant mass distributions for "bumps" that could indicate resonant production of new particles; and the Sleuth procedure scans for data excesses at large summed transverse momentum. This combined global search for new physics in 2.0/fb of ppbar collisions at sqrt(s)=1.96 TeV reveals no indication of physics beyond the standard model.Comment: 8 pages, 7 figures. Final version which appeared in Physical Review D Rapid Communication

Observation of Orbitally Excited B_s Mesons

We report the first observation of two narrow resonances consistent with states of orbitally excited (L=1) B_s mesons using 1 fb^{-1} of ppbar collisions at sqrt{s} = 1.96 TeV collected with the CDF II detector at the Fermilab Tevatron. We use two-body decays into K^- and B^+ mesons reconstructed as B^+ \to J/\psi K^+, J/\psi \to \mu^+ \mu^- or B^+ \to \bar{D}^0 \pi^+, \bar{D}^0 \to K^+ \pi^-. We deduce the masses of the two states to be m(B_{s1}) = 5829.4 +- 0.7 MeV/c^2 and m(B_{s2}^*) = 5839.7 +- 0.7 MeV/c^2.Comment: Version accepted and published by Phys. Rev. Let

Measurement of the Bs Lifetime in Fully and Partially Reconstructed Bs -> Ds- (phi pi-)X Decays in pbar-p Collisions at sqrt(s) = 1.96 TeV

We present a measurement of the Bs lifetime in fully and partially reconstructed Bs -> Ds(phi pi)X decays in 1.3 fb-1 of pbar-p collisions at sqrt(s) = 1.96 TeV collected by the CDF II detector at the Fermilab Tevatron. We measure tau(Bs) = 1.518 +/- 0.041 (stat.) +/- 0.027 (syst.) ps. The ratio of this result and the world average B0 lifetime yields tau(Bs)/tau(B0) = 0.99 +/-0.03, which is in agreement with recent theoretical predictions.Comment: submitted to Phys. Rev. Let

Observation of the Y(4140)Y(4140) structure in the J/ψ ϕJ/\psi\,\phi Mass Spectrum in B±→J/ψ ϕKB^\pm\to J/\psi\,\phi K cays

The observation of the $Y(4140)$ structure in $B^\pm\rightarrow J/\psi\,\phi K^\pm$ decays produced in $\bar{p} p$ collisions at \sqrt{s}=1.96~\TeV is reported with a statistical significance greater than 5 standard deviations. A fit to the $J/\psi\,\phi$ mass spectrum is performed assuming the presence of a Breit-Wigner resonance. The fit yields a signal of $19^{+6}_{-5}$ resonance events, and resonance mass and width of 4143.4^{+2.9}_{-3.0}(\mathrm{stat})\pm0.6(\mathrm{syst})~\MeVcc and 15.3^{+10.4}_{-6.1}(\mathrm{stat})\pm2.5(\mathrm{syst})~\MeVcc respectively. The parameters of this resonance-like structure are consistent with values reported from an earlier CDF analysis.Comment: 7 pages, 2 figures, submited to Phys. Rev. Let