GnRH removal in the 7-11 CO-Synch for timed insemination of beef heifers

The use of artificial insemination can improve genetics, shorten the calving season, and increase weaning weights by having more calves born earlier in the breeding season. Reasons that this technology has not been used by many producers may include poor conception rates, time, and cost. Research has been directed at shortening the synchronization time and controlling time of ovulation to eliminate estrous detection using a timed artificial insemination. Use of a progestin, like the Eazi-Breed CIDR or melengestrol acetate (MGA), is desirable because they are effective in synchronizing estrus and they can also induce cyclicity in anestrus or prepubertal females. In addition, gonadotropin releasing hormone (GnRH) is commonly included in a synchronization plan because it induces ovulation and synchronizes follicular development. The most common synchronization protocol for beef heifers consists of feeding MGA for 14 days, a prostaglandin injection 17 to 19 days later followed by five days of heat detection for a total duration of 36 to 38 days. Recent research suggests that acceptable conception rates can be achieved when shortening the time of MGA to seven days. One example is the 7-11 CO-Synch which is comprised of seven days of MGA feeding followed by the CO-Synch protocol starting on day 11 (see Figure 1). We have obtained greater then 60% conception rates using the 7-11 CO-Synch in previous years. The feeding of MGA not only synchronizes the estrous cycle but provides exposure to a progestin that may induce prepubertal heifers to begin cycling. The GnRH injection at day 11 should synchronize the follicular wave which will tighten the timing of ovulation and improve timed insemination conception rates. The disadvantage to this synchronization protocol is that it requires the heifers to go through the chute four times. It is also believed that heifers are less responsive to GnRH than cows. Thus we tested this protocol with or without the day 11 GnRH injection on conception rates of beef heifers

Modeling of a Boiler Pipe with Two-Phase Flow Instabilities

Tubes with boiling are common elements of many processes. They appear in steam generators and refrigerators and many other systems. The behavior of such systems is complicated and many physical phenomena are involved. It has for example been observed that different types of instabilities can occur. In this paper we will discuss modeling of tubes with boiling. As an application we will discuss an instability phenomenon due to pressure oscillations that has been observed experimentally in many different situations. We will first derive a simple analytical model which is able to capture the oscillations qualitatively. The simple model also gives insight into the mechanisms that generate the oscillations. A more complicated model is then built using a recently developed model base library in Modelica. A comparison between the simple and the complicated model is also give

Modeling and Dynamic Analysis of CO2-Emission Free Power Processes in Modelica using the CombiPlant Library

The need to reduce CO2 emissions from fossil-fuel based power production creates the need for new power plant solutions where the CO2 is captured and stored or reused. Different concepts to capture CO2 fall into the three main categories: 1. Precombustion decarbonization 2. Oxy-fuel combustion 3. Post-combustion removal of carbon. In the first two types of processes Oxygen Transport Membrane (OTM) is the key component, as pure oxygen is usually required to process reactions (e.g. Integrated Gasification Combined Cycle IGCC, Advanced Zero Emission Plant AZEP). Post-combustion removal processes can for example utilize adsorption/ desorption in certain salt solutions. This paper will describe two different applications of CO2- emission-free processes, one using an OTM, the other a high pressure post combustion removal process, the Sargas process, which has been modeled in a project with Siemens Industrial Turbomachinery AB and Alstom Power Sweden AB. All modeling work was carried out in the modeling language Modelica, which is an open standard for equation-based, object-oriented modeling of physical systems. System models have been built using the CombiPlant library, a modeling library for combined cycle power plants from Modelon AB

Effects of Colony Creation Method and Beekeeper Education on Honeybee (Apis mellifera) Mortality

The two-part study reported here analyzed the effects of beekeeper education and colony creation methods on colony mortality. The first study examined the difference in hive mortality between hives managed by beekeepers who had received formal training in beekeeping with beekeepers who had not. The second study examined the effect on hive mortality between hives that were initiated as nucleus or package colonies. Colonies created from package bees were more likely to survive for 1 year than nucleus colonies. Colonies managed by beekeepers who had received formal education also exhibited better survival rates than those managed by non-educated beekeepers

Multiyear Succession and Estate Planning for Farm and Ranch Families

Farm succession and estate planning pose difficult challenges for farmers. Idaho farmers generally do not have a business succession plan or an estate plan. Due to the complexities of farm management, University of Idaho Extension personnel partnered with the Idaho Barley Commission and the U.S. Department of Agriculture Risk Management Agency to develop a novel multiyear educational program. This program focused on introducing farm families to succession, retirement planning, and tax management strategies and motivating them to build and implement relevant plans. Findings indicate that participants increased their knowledge of succession and estate planning and completed and implemented major aspects of their management plans

Cloning and expression of pluripotent factors around the time of gastrulation in the porcine conceptus

Doctor of PhilosophyDepartment of Animal Sciences and IndustryDavid M. GriegerEarly in embryonic development a series of events occur whereby pluripotent cells undergo differentiation to give rise to the three germ layers and extraembryonic tissues of the developing conceptus. Nanog, Sox-2, and Oct-4 genes have been identified as having key roles in maintaining pluripotency in undifferentiated human and mouse cells but recent evidence suggests they may have different roles in farm animals. We cloned the coding sequence for porcine Nanog including 452 base pairs of the Nanog promoter, and partial coding sequences of Oct-4 and Sox-2. Embryos were flushed from sows 10, 12, 15, and 17 days post insemination. RNA was isolated from whole d-10 and -12 conceptuses, d-15 embryonic disk, distal and proximal extraembryonic tissue, and d-17 embryonic disk, distal and proximal extraembryonic tissue, and allantois for real-time PCR. RNA from d-40 maternal myometrium and endometrium, fetal placenta, and liver were also used in real-time PCR. The homeodomain and c-terminal tryptophan repeats are highly conserved in porcine Nanog compared to the mouse, human and bovine. In the promoter, the highly conserved Octamer and Sox binding sequences are also present. The Nanog expression pattern was different when compared to Oct-4 and Sox-2. Day-40 tissues demonstrated the highest expression including endometrium (7 fold) fetal liver (27 fold), placenta (40 fold) and myometrium (72 fold) when compared to day 15 distal extraembryonic tissue. Oct-4 and Sox-2 expression was lowest in d-40 tissues except for fetal liver which was 20 and 71 fold, respectively, higher than endometrium. Oct-4 levels were consistent in d-10, -12, and -15 conceptuses and disk but dropped 3 fold in d-17 disk. On the other hand, Sox-2 was upregulated a 1000 fold in the d-15 disk and 2000 fold in the d-17 disk when compared to the d-12 conceptus. Nanog may have other roles in than maintenance of pluripotency including a possible role in multipotent or progenitor stem cells. Expression of all 3 markers in fetal liver suggests a more primitive cell type is present such as hematopoietic stem cells

Ovarian responses and conception rates in response to gNrh, Hcg, and progesterone

We hypothesized that increasing concentrations of progesterone after artificial insemination (AI) would increase fertility. Our objective was to assess changes in ovarian structures, incidence of ovulation, and change in serum progesterone in response to GnRH, human chorionic gonadotropin (hCG), or exogenous progesterone (controlled internal drug release; CIDR insert) treatment, beginning 4 to 9 days after AI (d 0) and again 7 days later (Exp. 1). Blood was collected from 753 cows in 3 herds on days 0 and 7. Ovaries of 162 cows in 1 herd were scanned and mapped to confirm the presence a corpus luteum (CL), and cows were assigned randomly to serve as control (n = 41) or to receive a CIDR insert for 7 days (n = 41), 100 μg of GnRH (n = 40), or 3,300 IU of hCG (n = 40). More cows were induced to ovulate in response to GnRH (60%) and hCG (78%), compared with control (2.4%). Compared with control, cows treated with GnRH or hCG had more induced CL (d 7) and more total CL (d 7), but serum progesterone was increased only in response to hCG. Volume of the original luteal structures was increased by hCG, but tended to be reduced by CIDR and GnRH, compared with luteal volume in control. Total CL volume was increased by hCG, but reduced by CIDR, compared with CL volume of control. In Exp. 2, cows in 5 herds were used to assess conception rates in response to the same treatments described in Exp. 1: control (n = 708), CIDR (n = 711), GnRH (n = 719), and hCG (n = 714). Tendencies for interactions of treatment x herd and treatment x lactation group were detected, but no 3-way interactions were found. Treatment with hCG increased conception rates in second-lactation cows. The CIDR tended to increase, and hCG increased, conception rates in 2 herds, whereas the CIDR decreased conception rates in 1 herd. We concluded that GnRH and hCG effectively induced ovulation, and increased number of CL, but only hCG increased serum progesterone. Further, treatment with the CIDR or hCG increased conception rates, but only in some herds.; Dairy Day, 2006, Kansas State University, Manhattan, KS, 2006