Genetic parameters for conception rate and milk production traits within and across Holstein herds with different housing types and feeding systems during the first 3 lactations.

The housing types (HST) in which dairy cows are kept and the feeding systems (FDS) used differ among farmers in Japan. Here, we investigated the genetic relationships among conception rate at first insemination (CR) and milk production traits (PROD) during the first 3 lactations of Holstein cows by using a multiple-trait model that considered the trait values of herds with different HST [tiestall (TSL) barn, freestall (FS) barn, or grazing (GZ)] and FDS as separate traits. Milk production and conception records of Holstein cows in the Hokkaido region of Japan (283,611 records for first lactation, 253,902 for second, and 181,197 for third) were analyzed. We categorized herds with TSL or FS into 2 types of FDS for cows: separate feeding (SF) of roughage plus concentrate or feeding of total mixed ration, in which roughage and concentrates were mixed before feeding. The PROD analyzed were cumulative milk, fat, and protein yields within 305 d and lactation persistency, which we defined as the difference between milk yields at 240 and 60 d in milk. We estimated the heritabilities for CR or PROD within each HST or HST × FDS group and the genetic correlations between these traits within each group or across different groups within each lactation by using a 3-HST (TSL, FS, and GZ) × 2-trait (CR and each PROD) or 2-HST (TSL and FS) × 2-FDS × 2-trait animal model. Heritability estimates for CR in GZ were higher than those in TSL or FS, and genetic correlations for CR between GZ and TSL or FS barns were weaker than those between TSL and FS barns. In addition, genetic correlations between CR and PROD in GZ were weaker than those in TSL and FS barns. In the comparison among the 4 HST × FDS except GZ, heritability estimates for CR in FS × SF were higher than those in the others, and genetic correlations for CR between FS × SF and the other systems were relatively weak. These results indicated that differences in the production system for Holstein cows influence genotypic effects in terms of the cows' ability to conceive and the genetic relationships between fertility traits and milk production traits.

Genetic correlations between yield traits or days open measured in cows and semen production traits measured in bulls.

We used a bivariate animal model to investigate the genetic correlations between yield traits or days open (DO) as characters measured in cows and semen production traits as characters measured in bulls. Lactation records of 305-day milk, fat, and protein yields, and DO, from 386 809 first-lactation Holstein cows in Hokkaido, Japan, that calved between 2008 and 2014 were used. Semen production records were collected between 2005 and 2014 and included volume per ejaculate (VOL), sperm concentration (CON), number of sperm per ejaculate (NUM), progressive motility index of sperm (MOT), and MOT after freeze-thawing (A-MOT). Number of sperm per ejaculate was log-transformed into a NUM score (NUMS). A total of 30 373 semen production records from 1196 bulls were obtained. The pedigree file used for analysing the records was involving 885 345 animals. Heritability was estimated for VOL (0.42), CON (0.12), NUMS (0.37), MOT (0.08), and A-MOT (0.11). Weak and negative genetic correlations were recorded between yield traits measured in cows and VOL, CON or NUMS measured in bulls. Moderate and negative genetic correlations were obtained between DO and MOT (-0.42) or A-MOT (-0.43). Selection focused on MOT or A-MOT measured in bulls may therefore improve DO measured in cows.

Effects of stage of pregnancy on variance components, daily milk yields and 305-day milk yield in Holstein cows, as estimated by using a test-day model.

Pregnancy and calving are elements indispensable for dairy production, but the daily milk yield of cows decline as pregnancy progresses, especially during the late stages. Therefore, the effect of stage of pregnancy on daily milk yield must be clarified to accurately estimate the breeding values and lifetime productivity of cows. To improve the genetic evaluation model for daily milk yield and determine the effect of the timing of pregnancy on productivity, we used a test-day model to assess the effects of stage of pregnancy on variance component estimates, daily milk yields and 305-day milk yield during the first three lactations of Holstein cows. Data were 10 646 333 test-day records for the first lactation; 8 222 661 records for the second; and 5 513 039 records for the third. The data were analyzed within each lactation by using three single-trait random regression animal models: one model that did not account for the stage of pregnancy effect and two models that did. The effect of stage of pregnancy on test-day milk yield was included in the model by applying a regression on days pregnant or fitting a separate lactation curve for each days open (days from calving to pregnancy) class (eight levels). Stage of pregnancy did not affect the heritability estimates of daily milk yield, although the additive genetic and permanent environmental variances in late lactation were decreased by accounting for the stage of pregnancy effect. The effects of days pregnant on daily milk yield during late lactation were larger in the second and third lactations than in the first lactation. The rates of reduction of the 305-day milk yield of cows that conceived fewer than 90 days after the second or third calving were significantly (P<0.05) greater than that after the first calving. Therefore, we conclude that differences between the negative effects of early pregnancy in the first, compared with later, lactations should be included when determining the optimal number of days open to maximize lifetime productivity in dairy cows.

Genetic correlations between production and disease traits during first lactation in Holstein cows.

The aim of this study was to estimate genetic correlations between milk yield, somatic cell score (SCS), mastitis, and claw and leg disorders (CLDs) during first lactation in Holstein cows by using a threshold-linear random regression test-day model. We used daily records of milk, fat and protein yields; somatic cell count (SCC); and mastitis and CLD incidences from 46 771 first-lactation Holstein cows in Hokkaido, Japan, that calved between 2000 and 2009. A threshold animal model for binary records (mastitis and CLDs) and linear animal model for yield traits were applied in our multiple trait analysis. For both liabilities and yield traits, additive genetic effects were used as random regression on cubic Legendre polynomials of days on milk. The highest positive genetic correlations between yields and disease incidences (0.36 for milk and mastitis, 0.56 for fat and mastitis, 0.24 for protein and mastitis, 0.32 for milk and CLD, 0.44 for fat and CLD and 0.31 for protein and CLD) were estimated at about the time of peak milk yield (36 to 65 days in milk). Selection focused on early lactation yield may therefore increase the risk of mastitis and CLDs. The positive genetic correlations of SCS with mastitis or CLD incidence imply that selection to reduce SCS in the early stages of lactation would decrease the incidence of both mastitis and CLD.

Relationships between conception rate in Holstein heifers and cows and milk yield at various stages of lactation.

We investigated the relationships between conception rates (CRs) at first service in Japanese Holstein heifers (i.e. animals that had not yet had their first calf) and cows and their test-day (TD) milk yields. Data included records of artificial insemination (AI) for heifers and cows that had calved for the first time between 2000 and 2008 and their TD milk yields at 6 through 305 days in milk (DIM) from first through third lactations. CR was defined as a binary trait for which first AI was a failure or success. A threshold-linear animal model was applied to estimate genetic correlations between CRs of heifers or cows and TD milk yield at various lactation stages. Two-trait genetic analyses were performed for every combination of CR and TD milk yield by using the Bayesian method with Gibbs sampling. The posterior means of the heritabilities of CR were 0.031 for heifers, 0.034 for first-lactation cows and 0.028 for second-lactation cows. Heritabilities for TD milk yield increased from 0.324 to 0.433 with increasing DIM but decreased slightly after 210 DIM during first lactation. These heritabilities from the second and third lactations were higher during late stages of lactation than during early stages. Posterior means of the genetic correlations between heifer CR and all TD yields were positive (range, 0.082 to 0.287), but those between CR of cows and milk yields during first or second lactation were negative (range, -0.121 to -0.250). Therefore, during every stage of lactation, selection in the direction of increasing milk yield may reduce CR in cows. The genetic relationships between CR and lactation curve shape were quite weak, because the genetic correlations between CR and TD milk yield were constant during the lactation period.

Lactation persistency as a component trait of the selection index and increase in reliability by using single nucleotide polymorphism in net merit defined as the first five lactation milk yields and herd life.

We first sought to clarify the effects of discounted rate, survival rate, and lactation persistency as a component trait of the selection index on net merit, defined as the first five lactation milks and herd life (HL) weighted by 1 and 0.389 (currently used in Japan), respectively, in units of genetic standard deviation. Survival rate increased the relative economic importance of later lactation traits and the first five lactation milk yields during the first 120 months from the start of the breeding scheme. In contrast, reliabilities of the estimated breeding value (EBV) in later lactation traits are lower than those of earlier lactation traits. We then sought to clarify the effects of applying single nucleotide polymorphism (SNP) on net merit to improve the reliability of EBV of later lactation traits to maximize their increased economic importance due to increase in survival rate. Net merit, selection accuracy, and HL increased by adding lactation persistency to the selection index whose component traits were only milk yields. Lactation persistency of the second and (especially) third parities contributed to increasing HL while maintaining the first five lactation milk yields compared with the selection index whose only component traits were milk yields. A selection index comprising the first three lactation milk yields and persistency accounted for 99.4% of net merit derived from a selection index whose components were identical to those for net merit. We consider that the selection index comprising the first three lactation milk yields and persistency is a practical method for increasing lifetime milk yield in the absence of data regarding HL. Applying SNP to the second- and third-lactation traits and HL increased net merit and HL by maximizing the increased economic importance of later lactation traits, reducing the effect of first-lactation milk yield on HL (genetic correlation (rG) = -0.006), and by augmenting the effects of the second- and third-lactation milk yields on HL (rG = 0.118 and 0.257, respectively).

Entropy-controlled asymmetric synthesis. How differential activation entropy is induced in chiral tethered reactions.

[figure: see text] Kinetic measurements to determine effective molarities of intramolecular reactions using 2,4-pentanediol and related tethers showed that methyl groups on the tether accelerate the major diastereomeric process but decelerate the minor process. The efficient promotion of stereocontrol is suggested to be due to chiral perturbation of the reaction rate through the entropy term. The conformation of the encounter complex of the reagent and reactant moieties was deduced by stereochemical analysis of the intramolecular adducts.

Commensurate structure of Ca(2)CoSi(2)O(7), a new twinned orthorhombic structure.

The crystal structure of the commensurate phase of Ca(2)CoSi(2)O(7), dicalcium cobalt disilicate, has been derived from the modulated structure described in (3 + 2)-dimensional space. The structure is orthorhombic P2(1)2(1)2; a = 23.510 (4), b = 23.510 (4), c = 5.025 (1) A (at 170 K), Z = 18. Since the crystal is twinned and the apparent diffraction symmetry is 4/mmm, the parameters were refined by a newly developed least-squares program for the refinement of twinned crystals. The structure is essentially similar to the known structure of the melilite group, but with regular arrangement of the bundles along [001] formed with four arrays of the sixfold coordinated Ca polyhedra and an array of CoO(4) tetrahedra. The distribution of the bundles found in the present structure is different from that reported by Riester et al. [(2000), Z. Kristallogr. 215, 102-109].

Two-dimensional incommensurately modulated structure of (Sr0.13Ca0. 87)2CoSi2O7 crystals.

The incommensurate structure of (Sr(0.13)Ca(0.87))(2)CoSi(2)O(7) at room temperature has been determined from single-crystal X-ray diffraction data. The compound has a non-centrosymmetric tetragonal basic cell of a = 7.8743 (4) and c = 5.0417 (2) A with the space group P4;2(1)m. The refinements of the basic structure converged to R = 0.038 for 757 main reflections. The two-dimensional incommensurate structure is characterized by the wavevectors q(1) = 0.286 (3)(a* + b*) and q(2) = 0.286 (3)(-a* + b*), where a*, b* are the reciprocal lattice vectors of the basic structure. With the (3 + 2)-dimensional superspace group P(p4mg)(P4;2(1)(m)), the refinements converged to R = 0.071 for 1697 observed reflections (757 main and 940 satellite reflections). The structure is described in terms of displacement of the atoms, rotation, distortion of CoO(4) and SiO(4) tetrahedra, and the partial ordering of the Sr and Ca atoms accompanied with the modulation. Correlated evolution of these features throughout the crystal gives rise to various oxygen coordination around Ca/Sr. Comparison of the derived modulated structure to that of Ca(2)CoSi(2)O(7) clarified that the partial substitution of Ca by large alkaline-earth atoms such as Sr should decrease the distortion of the polyhedra around the cations.

Mental disturbances during isolation in bone marrow transplant patients with leukemia.

The mental status of 39 leukemia patients, who received bone marrow transplants (BMT), was studied during the period of isolation. Mental disorders (diagnosed according to DSM-IV criteria) occurred in 16 patients (41%) during the observation period. The most frequent diagnoses were adjustment disorders, with anxiety and/or depression. Logistic regression analysis suggested higher Tension-Anxiety score in the Profile of Mood States (POMS) prior to isolation (P = 0.011), donation of the bone marrow from unrelated subjects (P = 0.026) and in female patients (P = 0.033). The results are preliminary, but indicate a high frequency of mental disturbances and highlight the importance of psychiatric intervention in BMT patients. Bone Marrow Transplantation (2000) 25, 315-318.

Formation of mineralized bone nodules by rat calvarial osteoblasts decreases with donor age due to a reduction in signaling through EP(1) subtype of prostaglandin E(2) receptor.

The effects of prostaglandin E(2) (PGE(2)) on the parameters for proliferation and differentiation were studied in calvarial osteoblast-like cells isolated from rats of various ages. In cells not treated with PGE(2), it was found that mineralized bone nodule (BN) formation, alkaline phosphatase (ALP) activity, and the incorporation rate of [(3)H]thymidine into the cells sharply decreased with the age of the cell donor at 6-50 weeks and then remained at a relatively constant level up to 120 weeks. Before studying the effects of PGE(2) on these parameters, we determined the change in the levels of PGE(2) produced by the untreated cells during the culture period and found that the endogenous PGE(2) reached a maximum on the 4th day of the culture, regardless of the cell donor age, followed by a sharp decrease. The endogenous production was blocked by pretreatment with a cyclooxygenase-2 (COX-2) inhibitor, NS-398, indicating the generation of PGE(2) through a COX-2 pathway. The area of BN was effectively suppressed by NS-398 in the cells from 10- to 35-week-old rats, whereas it was enhanced in the cells from 90- to 120-week-old rats. Treatment with PGE(2 )markedly increased the BN formation and the ALP activity in the cells from 4- to 35-week-old rats (defined as young rats). By contrast, PGE(2) decreased [(3)H]thymidine incorporation into the cells from young rats. The area of BN and the ALP activity decreased significantly, whereas [(3)H]thymidine incorporation into the cells increased by 60-80% in the cells of 80- to 120-week-old rats (defined as aged rats). The stimulatory effects on the cell differentiation and the inhibitory effect on the proliferation in the cells from young rats was mimicked by an EP(1) agonist, 17-phenyl-omega-trinor PGE(2), while an EP(2)/EP(4) agonist, 11-deoxy-PGE(1) and an adenylate cyclase activator, forskolin suppressed the differentiation and enhanced the proliferation regardless of the cell donor age. PGE(2), 11-deoxy-PGE(1) and forskolin, but not 17-phenyl-omega-trinor PGE(2) increased cyclic adenosine monophosphate (cAMP) production. Generation of inositol 1, 4,5-triphosphate (IP(3)) was stimulated by 17-phenyl-omega-trinor PGE(2) or PGE(2), but not by 11-deoxy-PGE(1) or forskolin increased cAMP production in the cells from young rats. By contrast, PGE(2 )had little effect on IP(3 )generation in aged rats. From the overall results, we concluded that PGE(2) exerts stimulatory and inhibitory effects on differentiation through the EP(1)-IP(3) pathway and EP(2)/EP(4)-cAMP pathway, respectively, in the cells from young rats. The EP(1)-IP(3) pathway seems to be inactive in the cells from aged rats.