Sveberg G.,GENO Breeding and AI Association |
Refsdal A.O.,GENO Breeding and AI Association |
Erhard H.W.,Agro ParisTech |
Erhard H.W.,French National Institute for Agricultural Research |
And 5 more authors.
Journal of Dairy Science | Year: 2011
The objectives of the present study were to describe, in detail, behavior associated with standing estrus (STE) in lactating dairy cows and behavioral changes during complete estrous cycles. Estrus signs were monitored by continuous video recording of 20 Holstein-Friesian (HF) cows housed on an outdoor wood-chip pad during 1 estrous cycle (22 d). Other social behavior was recorded during STE and, for comparison, during 1 selected day when none of the cows were in estrus. Standing stationary when mounted was defined as the primary estrus sign. Anogenital sniff, chin rest, attempt to mount, and mount were defined as secondary estrus signs. Ovarian cyclicity was confirmed by progesterone measurements. This study reports short mean duration of STE (7.1 ± 1.44. h) and estrus (mount period; 12.9 ± 1.84. h) of the 13 cows expressing these signs. All mounting activities involved at least one cow in, or within 4. h of, STE. The most frequent sign during STE was anogenital sniff initiated, followed by chin rest received, chin rest initiated, chase up initiated, anogenital sniff received, mount initiated, head butt, mount received, attempt to mount initiated, push away received, play rub, attempt to mount received, follow initiated, threat received, flehmen, avoid, bellow, and social lick received. Standing and mounting activity in HF cows was inconsistent during estrus, indicating that other signs could be of greater use. The frequency of secondary estrus signs initiated and received increased gradually during the last 12. h before STE, revealing significant differences between periods from 4 to 6 and 1 to 3. h before STE. A considerable increase in receptive behavior (secondary estrus signs received) was identified between 1 to 3. h prior to STE and STE. Both frequent initiated and received behaviors were associated with STE. A significant decrease in the frequency of secondary estrus signs initiated and received occurred 3. h after STE. Cows in STE simultaneously predominantly chose the other standing cow as mate and expressed secondary estrus signs more frequently. Based on the results of this study, we suggest that chase up could be regarded as a reliable indicator of estrus and that the changes in proceptive (initiated) and receptive (received) behavior could be used as predictors of different stages in estrus. Knowledge of these behavioral signs may improve heat detection rates and the ability to predict the optimum breeding time for dairy cows. © 2011 American Dairy Science Association.
Alm-Kristiansen A.H.,University of Oslo |
Alm-Kristiansen A.H.,BioKapital AS |
Lorenzo P.I.,University of Oslo |
Molvaersmyr A.-K.,University of Oslo |
And 4 more authors.
Molecular Cancer | Year: 2011
Background: FLASH is a huge nuclear protein involved in various cellular functions such as apoptosis signalling, NF-κB activation, S-phase regulation, processing of histone pre-mRNAs, and co-regulation of transcription. Recently, we identified FLASH as a co-activator of the transcription factor c-Myb and found FLASH to be tightly associated with active transcription foci. As a huge multifunctional protein, FLASH is expected to have many interaction partners, some which may shed light on its function as a transcriptional regulator.Results: To find additional FLASH-associated proteins, we performed a yeast two-hybrid (Y2H) screening with FLASH as bait and identified the SUMO E3 ligase PIAS1 as an interaction partner. The association appears to involve two distinct interaction surfaces in FLASH. We verified the interaction by Y2H-mating, GST pulldowns, co-IP and ChIP. FLASH and PIAS1 were found to co-localize in nuclear speckles. Functional assays revealed that PIAS1 enhances the intrinsic transcriptional activity of FLASH in a RING finger-dependent manner. Furthermore, PIAS1 also augments the specific activity of c-Myb, and cooperates with FLASH to further co-activate c-Myb. The three proteins, FLASH, PIAS1, and c-Myb, are all co-localized with active RNA polymerase II foci, resembling transcription factories.Conclusions: We conclude that PIAS1 is a common partner for two cancer-related nuclear factors, c-Myb and FLASH. Our results point to a functional cooperation between FLASH and PIAS1 in the enhancement of c-Myb activity in active nuclear foci. © 2011 Alm-Kristiansen et al; licensee BioMed Central Ltd.
Waterhouse K.,BioKapital AS
Reproduction in Domestic Animals | Year: 2013
With the aim of investigating the relationship between sperm DNA integrity and non-return rate (NRR) among Norwegian cross-bred rams, semen from 15 individuals was examined by flow cytometry. Sperm Chromatin Structure Assay (SCSA) quantifies the proportion of spermatozoa with denatured DNA after in situ acid treatment, and the four parameters % DFI, % HDS, MEAN DFI and SD DFI are all different measures of DNA denaturation and maturation. Field fertility, reported as NRR 25days after insemination was based on all inseminations from a large-scale breeding programme and supplied by the Norwegian Association of Sheep and Goat Farmers. From each ram, four straws from four different weeks of the breeding season were analysed, and the associations between 25-day NRR and the mean of the four SCSA parameters were tested using a logistic regression model. The results revealed no association between fertility and % DFI or % HDS, while SD DFI and MEAN DFI showed a significant negative association with NRR. Further, the SCSA values varied significantly between ejaculates within ram among some of the rams in the study. However, no significant association was seen between these intra-individual differences in sperm DNA integrity and NRR. In conclusion, this study suggests an association between sperm DNA integrity and NRR for rams. However, further research must be conducted to confirm these findings and determine whether sperm DNA assessments can be applied to predict ram fertility. © 2012 Blackwell Verlag GmbH.
Oskam I.,BioKapital AS |
Tajet H.,Norwegian Pig Breeders Association Norsvin
Theriogenology | Year: 2013
Androstenone and testosterone levels in Duroc boars with an estimated breeding value for androstenone (EBVandrostenone) were followed in the period from birth to sexual maturity. The breeding value for androstenone had been estimated based on androstenone levels in 1202 Duroc boars at an age of 24 weeks. Testosterone and androstenone levels in plasma were recorded in 19 boars at 1 week of age and in their 15 respective litter-siblings at 3 weeks of age. Between 12 and 27 weeks of age, plasma levels were recorded weekly in a third set of 16 litter-siblings. In the last group, histomorphology was performed at 12, 16, 20, and 27 weeks of age to determine sexual maturity status. The EBVandrostenone was positively related to plasma androstenone in animals 12 to 27 weeks of age and to plasma testosterone levels in 1- and 3-week-old animals. The EBVandrostenone was not related to testis morphology. The concentration of fat androstenone was positively correlated to the percentage of immature seminiferous tubules and negatively correlated to the percentage of mature seminiferous tubules at 20 weeks. Testosterone in plasma showed no relationship with testis morphology. Most individuals reached puberty at 20 weeks of age, which indicates that Duroc mature later than crossbred boars. The results indicated that breeding value based on the single trait boar taint parameter EBVandrostenone was not related to testicular development. © 2013 Elsevier Inc.