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Evaluation Of The Effects Of A Contract Breeding Program On Reproductive Efficiency In Ohio Dairy Herds
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Book Synopsis Evaluation of the Effects of a Contract Breeding Program on Reproductive Efficiency in Ohio Dairy Herds by : Cheyney Meadows
Download or read book Evaluation of the Effects of a Contract Breeding Program on Reproductive Efficiency in Ohio Dairy Herds written by Cheyney Meadows and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Reproductive inefficiency is a significant problem facing modern dairy herds. The research herein discusses issues related to reproductive efficiency of dairy herds in three distinct sections. The use of electronic herd records is an important component of troubleshooting a herd's reproductive performance. Herd record analysis must be coupled with a herd visit and clinical examinations of individual cows to try to identify factors that are limiting reproductive success. One component of this document describes methodology for monitoring reproductive performance of dairy herds and possible reasons for reproductive failure. While reproductive inefficiency is costly to dairy producers, loss estimates vary because of the conditions under which they are evaluated. Another aspect of this research has been the development of a model to be used for estimating economic effects of changes in reproductive performance under specific situations. It is shown that the magnitude of economic effects are sensitive to market prices faced by dairy producers as well as the herd's current level of reproductive performance. A very common management problem limiting reproductive efficiency in Ohio dairies is the failure to efficiently and accurately detect estrus. A novel approach to the estrus detection problem currently being offered to Ohio dairies is for producers to contract estrus detection activities and breeding decisions to outside parties. A field study involving 32 herds was conducted in order to evaluate the efficacy of such a reproductive management program. At the start of data acquisition, 16 of the herds were enrolled in the management program; two non-program herds began using the program and two program herds stopped using the program during the data acquisition phase. Electronic reproductive data was collected for at least 18 months on all participating herds and analyzed. Results indicated that the program was associated with statistically significant improvements in some aspects of reproductive performance. The program did not appear to affect economic performance.
Book Synopsis Dissertation Abstracts International by :
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2005 with total page 768 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Effects of a Herd Health Program on Reproductive Performance of Dairy Cows by : David Malcolm Galton
Download or read book Effects of a Herd Health Program on Reproductive Performance of Dairy Cows written by David Malcolm Galton and published by . This book was released on 1976 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Evaluation of Reproductive Efficiency in Lactating Dairy Cows Through Physiologic Evaluation and Synchronization Modification by : Charles Dexter Young
Download or read book Evaluation of Reproductive Efficiency in Lactating Dairy Cows Through Physiologic Evaluation and Synchronization Modification written by Charles Dexter Young and published by . This book was released on 2015 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reproductive performance of lactating dairy cows has decreased as milk production has increased as a result of genetic selection. Milk production alone is not the reason for decreased reproductive performance, as fertility issues are multifactorial and collaborative. Research chapters contained within have taken an applied approach focusing in two different areas of fertility. One approach was development of an evaluation system to identify lactating cows with decreased fertility prior to breeding; while another approach was to modify an ovulation synchronization protocol during periods of heat stress in order to improve fertility. The first focus was development and evaluation of a size and position score based on a one to three scale and assigned to lactating cows during a pre-breeding exam. This score was a reflection of the cervical and uterine horn diameter, and of the position of the reproductive tract in relation to the pelvis. Results indicated that cows with the largest reproductive tracts (score 3) had a 15% decrease in conception rates following artificial insemination compared to the smallest reproductive tracts (score 1). Score two reproductive tracts (intermediate) exhibited decreased conception rates compared to score one, but greater than score three. Identification of cows with lower potential fertility will allow producers to make the most economically, efficient decision when artificially inseminating lactating dairy cows. The second research focus modified an ovulation synchronization protocol by including an intravaginal progesterone releasing device (CIDR) nine days prior to artificial insemination during periods of heat stress. Use of a CIDR has shown to be beneficial with modest improvements in fertility in cool seasons, especially in anovular cows. This modification did not prove to be beneficial in improving conception rates during periods of heat stress. Lactating dairy cows with or without a progesterone releasing device had comparable conception rates. This research remains informative since use of a CIDR is expensive. This research exhibits this additional expense does not lead to positive results, thereby discouraging producers from incurring an unnecessary expense.
Book Synopsis Economic Evaluation of Dairy Reproductive Health Indicators Based on Active Breeding Group Analysis by : Patrick J. Hady
Download or read book Economic Evaluation of Dairy Reproductive Health Indicators Based on Active Breeding Group Analysis written by Patrick J. Hady and published by . This book was released on 1992 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis The Effects of Milk Production and Management on Reproductive Performance in Wisconsin Dairy Herds by : Cheryl F. Marti
Download or read book The Effects of Milk Production and Management on Reproductive Performance in Wisconsin Dairy Herds written by Cheryl F. Marti and published by . This book was released on 1993 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis The Effects of Various Postpartum Treatments Upon the Reproductive Efficiency of Dairy Cows by : Nicholas de Domincis Brown
Download or read book The Effects of Various Postpartum Treatments Upon the Reproductive Efficiency of Dairy Cows written by Nicholas de Domincis Brown and published by . This book was released on 1958 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Evaluation of the Effects of Heifer Development Method on Subsequent Reproductive Performance and Progeny Growth by : Amanda Jillian Cain
Download or read book Evaluation of the Effects of Heifer Development Method on Subsequent Reproductive Performance and Progeny Growth written by Amanda Jillian Cain and published by . This book was released on 2016 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of the present study was to evaluate the effects of low input development protocols on Southeastern replacement beef females and their offspring. Fall and spring calving crossbred beef heifers managed through one of two heifer development programs (low input, LOW or conventionally developed, CON) were evaluated for metrics of uterine artery hemodynamics, patterns of heifer and offspring growth, postpartum reproductive performance, and economic efficiency. There were significant treatment × season (P = 0.0001) and season × day (P = 0.003) interactions on heifer body weight (BW) during gestation. There was a season × day interaction on total blood flow (TBF; P = 0.05) whereby TBF increased as gestation progressed and spring calving heifers displayed increased TBF. When adjusted for BW, an additional main effect of treatment was observed (P = 0.0007) in which LOW heifers had increased TBF compared to CON heifers. There were no significant main effects of treatment or season or interactions thereof on the proportion of females cycling at the start of the breeding season (P > 0.05). Additionally, there were main effects of treatment (P = 0.0095; P = 0.02) and season (P = 0.012; P = 0.007) on calf ADG and weaning weights, respectively whereby calves born to CON females grew faster than calves born to LOW heifers, and SPRING calves gained more rapidly than FALL calves. Partial budgeting demonstrated that LOW bred heifers were $250/hd less expensive to purchase than CON heifers due to lighter BW. Calves born to LOW females yielded $6.38 less per calf compared to CON calves. The discrepancy in reproductive efficiency coupled with the failure of LOW females to achieve BW similar to CON females resulted in a difference of $403/hd in average cull value between LOW and CON females in which CON females were worth more. Thus, CON females were $159.18 more profitable than LOW females when purchased as bred heifers and sold at the weaning of their first calf. In conclusion, though uterine artery BF was not negatively affected, low input heifer development resulted in sub-optimal heifer growth, poor first calf performance, and inadequate reproductive efficiency.
Book Synopsis Strategies to Improve Reproductive Efficiency Through Systematic Breeding Programs in Dairy Cows by : Rabiou Manzo
Download or read book Strategies to Improve Reproductive Efficiency Through Systematic Breeding Programs in Dairy Cows written by Rabiou Manzo and published by . This book was released on 2003 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Optimum Reproductive Efficiency in Dairy Herds by : J. N. Maddux
Download or read book Optimum Reproductive Efficiency in Dairy Herds written by J. N. Maddux and published by . This book was released on 1982 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Development and Evaluation of Models for Predicting Reproductive Performance in Large Commercial Dairy Herds by : Daniel Zeraib Caraviello
Download or read book Development and Evaluation of Models for Predicting Reproductive Performance in Large Commercial Dairy Herds written by Daniel Zeraib Caraviello and published by . This book was released on 2005 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Evaluating Reproductive Management Changes in a Dairy Herd by : Corey Catherine Risch
Download or read book Evaluating Reproductive Management Changes in a Dairy Herd written by Corey Catherine Risch and published by . This book was released on 2002 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Synchronization and Ovarian Development in Dairy Cows and Heifers by : Rebecca L. J. Coral Escalante
Download or read book Synchronization and Ovarian Development in Dairy Cows and Heifers written by Rebecca L. J. Coral Escalante and published by . This book was released on 2012 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reproductive management is an important factor for improving reproductive efficiency in the dairy industry. Reproductive efficiency affects the profitability of the dairy herd by decreasing days not pregnant and increasing milk produced in a cow's lifetime. There are many reproductive programs used to synchronize the estrous cycle. Prostaglandin F2[alpha] (PGF2[alpha])-based programs synchronize estrus before artificial insemination (AI) after observed estrus. Some disadvantages to PGF2[alpha]-based reproductive programs are time requirements necessary for estrus detection (2 to 3 times/d for about 30 min) and lack of estrus activity observed in dairy cows (only about 40% will show estrus). An advantage to PGF2[alpha]-based reproductive programs is acceptable conception rates (about 45 to 60%) that can surpass timed AI (TAI). Reproductive programs that employ TAI are achieved by synchronization of ovulation with a series of PGF2[alpha] and gonadotropin releasing hormone (GnRH) injections followed by insemination 16 h later. Some of the advantages to synchronization of ovulation followed by TAI are: no estrus detection and acceptable conception rates (40 to 50%). Many reproductive programs include a presynchronization step. The advantage to presynchronization is a tightened synchrony by getting more cows and heifers in the same stage of the estrous cycle before estrous synchronization and AI or TAI. There are a variety of presynchronization methods used in cattle. One of the most common programs is two injections of PGF2[alpha] 14 d apart 12 d before initiation of Ovsynch (d 0 GnRH, 7 d, PGF2[alpha], 56 h, GnRH, 16 h, TAI) (Moreira et al., 2001). Another is double Ovsynch where the Ovsynch program is administered 7 d before another Ovsynch program (Giordano et al., 2012). Long-term progestogens can also be used as a means to presynchronize the estrous cycle and has been successful in beef cows and heifers. Long term progestogens, such as a CIDR (controlled internal drug release) for 14 d, will suppress estrus, inhibit ovulation, and induce the development of a persistent dominant follicle that can ovulate after CIDR removal (Ahmad et al., 1995; Revah and Butler, 1996; Roche et al., 1999). Ovulation of the dominant follicle allows for cows and heifers to be late in the luteal stage of the estrous cycle before PGF2[alpha] and AI or PGF2[alpha], 56 h, GnRH, 16 h, TAI. Presynchronization has shown to decrease the days to pregnancy. This is an advantage because it will directly affect the number of days a cow is not pregnant and the amount of milk she will produce in her lifetime. The objective of this research was to evaluate pregnancies per AI, ovarian follicular and luteal development of postpartum dairy cows and dairy heifers in response to long term progestin-based programs (14dCIDR) compared with PGF2[alpha]-based programs. Experiment 1 (Chapter 2) evaluated the use of a 14dCIDR-PGF2[alpha] program to a PGF2[alpha]-alone program for synchronizing dairy heifers before AI. Heifers were examined by real-time ultrasonography during treatment to assess the ovarian response. Heifers were also monitored for estrus following presynchronization and treatment of PGF2[alpha] to assess ovulation response. The 14dCIDR-PGF2[alpha] system resulted in more heifers with a larger CL at the time of PGF2[alpha]. This is ideal because of the greater luteolytic effects of PGF2[alpha] has on a more mature CL. The 14dCIDR-PGF2[alpha] heifers were AI and became pregnant sooner compared with the PGF2[alpha]-alone heifers. Experiment 2 (Chapter 3) evaluated the use of a 14dCIDR_TAI program compared with a PGF2[alpha]-based program in grazing dairy cows. The 14dCIDR_TAI program employed synchronization of ovulation before TAI and the PGF2[alpha]-based program employed synchronization of estrus with AI after observed estrus. The evaluation of reproductive efficiency for each program was examined. Cows assigned to the 14dCIDR_TAI program were AI early in the breeding season and were all AI by the end the breeding season compared with the PGF2[alpha]-based program. The PGF2[alpha]-based program had a greater first service conception rate (FSCR) compared with the 14dCIDR_TAI program but did not achieve a greater number of pregnancies after two inseminations. Experiment 3 (Chapter 4) evaluated the use of a 14dCIDR_TAI program compared with another common TAI program (Presynch-Oysynch56) in postpartum lactating dairy cows. Follicular dynamics and luteal development were monitored in both programs. Each program was evaluated for effectiveness to presynchronize the estrous cycle and establish pregnancy. The 14dCIDR_TAI and the Presynch-Ovsynch56 programs were comparable in their effectiveness to presynchronize the estrous cycle and establish pregnancy in cows that were cycling. Non-cycling cows treated with the Presynch-Ovsynch56 program had lesser conception rate compared with those that were cycling. There was no difference in conception rate with non-cycling or cycling cows treated with the 14dCIDR_TAI. Experiment 4 (Chapter 5) evaluated the use of the 14dCIDR_TAI program with or without PGF2[alpha] at CIDR removal. It is possible for cows to still have a CL after the end of the 14dCIDR treatment either due to longer estrous cycles or the cow was early in her estrous cycle when the CIDR was inserted. The addition of PGF2[alpha] may help improve the synchrony and conception rates after presynchronization of the estrous cycle before TAI. The addition of the PGF2[alpha] at CIDR removal demonstrated an increase in the number of cows that showed estrus after presynchronization but conception rates were comparable. Overall, the use of the 14dCIDR as means to presynchronize the estrous cycle has been demonstrated as an effective way to enhance the synchrony and decrease the interval to pregnancy in dairy cows and heifers.
Book Synopsis Genomically Enhanced Predictions of Dairy Cattle Fertility by : Emily Marie Sitko
Download or read book Genomically Enhanced Predictions of Dairy Cattle Fertility written by Emily Marie Sitko and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Research presented in this thesis aimed at improving the efficiency of dairy farms through the development of targeted reproductive management strategies (TRM) based on genomically enhanced predictions of fertility, and the elucidation of associations between genetic merit for fertility and biological outcomes that affect dairy cow reproductive performance.Chapter II and III present the results of an experiment designed to compare the association between genetic merit for fertility and reproductive and profitability outcomes of cows submitted for artificial insemination (AI) with management programs that prioritized AI at detected estrus (AIE) or timed AI (TAI). Another objective was to determine if cows with different genetic potential for fertility would present a distinct response to the strategies compared. The study presented in Chapter IV and V characterized associations between genetic merit for fertility and biological parameters known to alter reproductive performance of cows. Results presented in Chapter II and III indicated that primiparous Holstein cows of superior genetic merit for fertility had better reproductive performance than cows of inferior genetic merit for fertility regardless of the type of reproductive management used. In addition, the effect of TRM based on genetic merit for fertility on reproductive performance depended on the outcome or sets of outcomes of interest evaluated. For example, cows of superior and intermediate genetic merit for fertility had greater P/AI when managed with the predominant TAI program but reduced days to pregnancy when managed with the program that prioritized AIE. Cows of inferior fertility also had greater first service P/AI with the program that prioritized TAI but had similar days to pregnancy with both management strategies. From an economic standpoint, cows of inferior fertility had greater cash flow than cows of superior fertility. For cows in specific fertility groups, the effects of the reproductive management strategies compared generated differences in cash flow of potential value for commercial dairy farms. The study presented in Chapter IV and V demonstrated a potential association of genomic merit for fertility with physiological and endocrine parameters known to affect reproductive performance of dairy cows. Particularly, cows of inferior genetic merit for fertility had poorer uterine health, decreased response to synchronization of estrus and ovulation, and were more likely to present altered ovarian and hormonal phenotypes that led to more frequent expression of atypical estrous cycles as compared with cows of superior genetic merit for fertility. Overall, we observed that genetically enhanced predictions of fertility might be a suitable tool for decision making in TRM. Additionally, the value of TRM programs for cows of different genetic merit for fertility might be on improving aspects of herd management such as simplifying program implementation or reducing reliance on hormonal interventions while maintaining acceptable levels of reproductive performance. An improved understanding of biological differences associated with genetic variation, such as our observations in Chapter IV and V, may be beneficial for the development of novel TRM and technologies to improve the reproductive efficiency of dairy cattle. This novel information could also support the development of new traits for selection of fertility.
Book Synopsis The Effect of Delayed Breeding of Dairy Cows on Milk Yield, Reproductive Efficiency and Economic Returns to Dairy Producers by :
Download or read book The Effect of Delayed Breeding of Dairy Cows on Milk Yield, Reproductive Efficiency and Economic Returns to Dairy Producers written by and published by . This book was released on 1985 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Factors Affecting Reproductive Efficiency in Dairy Cattle by : Durward Olds
Download or read book Factors Affecting Reproductive Efficiency in Dairy Cattle written by Durward Olds and published by . This book was released on 1954 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Analysis of the Reproductive Efficiency of the Dairy Herd at Western Kentucky University Farm by : Gregorio Garcia Lagombra
Download or read book Analysis of the Reproductive Efficiency of the Dairy Herd at Western Kentucky University Farm written by Gregorio Garcia Lagombra and published by . This book was released on 1985 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:
