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Showing 1 to 12 of 12 for “"Detection of estrus"”.
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Electrical Conductivity of Reproductive Tissue for Detection of Estrus in Dairy Cows
Inefficient detection of estrus is the principal cause of delayed conception and concomitant lengthened calving intervals. Consequently, interest is generated in devising new methods of detecting estrus. Electrical conductivity of reproductive tissue can be a potential method of doing so.
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Relationship Between Physical Activity, Stage of Estrous Cycle, Sexual Behavior and Plasma Luteinizing Hormone in Dairy Cattle (Electronic Pedometers)
Detection of estrus remains as one of the major factors affecting reproductive performance in dairy cattle. Use of electronic equipment such as programmable electronic pedometers may assist detecting changes in physical activity that occur during the day of estrus in cattle.
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Use of Triptorelin Acetate for Inducing Ovulation and Facilitating Fixed Time Artificial Insemination of Sows Weaned on Small-Scale and Niche Market Pig Farms
… decreasing semen costs and labor associated with detection of estrus. The objective of this study was to test the efficacy of an artificial insemination (AI) breeding system using triptorelin acetate, a GnRH agonist (OvuGel®; JBS United Animal Health, LLC, Sheridan, IN) that induces ovulation. A …
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Comparison of three estrus detection systems during summer heat stress in a large commercial dairy herd
The objective of the study was to compare three systems for detection of estrus and combinations of these systems on a large commercial dairy (1000 lactating cows) during stress of summer heat. At 37 to 45 days in milk (DIM), 266 cows were fitted with a HeatWatch (HW) device (HeatWatch; DDx Inc., …
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Development of an expert system for the evaluation of reproductive performance and management of Virginia dairy farms
… days open, days to first insemination, percent of possible estruses observed, and number of breedings per conception to determine whether a problem exists. Interpretations ranging from “excellent” to “severe” were established for each parameter. “Excellent” and “adequate” interpretations …
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Effect of P.G. 600 on the timing of ovulation in gilts treated with Regu-mate
… We hypothesized that P.G. 600 altered the timing of ovulation, therefore mating gilts 12 and 24 h after first detection of estrus, as is common in the swine industry, may not have been the most appropriate breeding regimen. The objective of this study was to determine the effect of P.G. 600 on the …
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Effect of Timing of Insemination and Synchronization of Estrus Method on Artificial Insemination (AI) Pregnancy Rates in Beef Heifers
Objectives were to evaluate time of insemination relative to estrus and synchronization with melengestrol acetate (MGA) plus prostaglandin (PG) or progesterone insert (CIDR) plus PG on AI pregnancy rate in beef heifers (n = 662) during Fall or Spring. Fall heifers (n = 349) received MGA-PG (MGA for …
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The Interaction of Sire Fertility and Timing of AI in a Synchronization Protocol
The objectives of this study were to determine if fixed-timed artificial insemination (FTAI) at two different times, 0 or 24 h after GnRH administration, in a Presynch-Ovsynch protocol influenced the pregnancy rate (PR) when average and high fertility sires were used. Additionally, a second …
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Evaluation of systematic breeding programs in lactating dairy cows
Observing cows in estrus and inseminating them at the optimal time are necessary steps for effective reproductive management of a dairy herd. However, increasing herd sizes can lead to reproductive inefficiency resulting in decreased profits on dairy herds. Synchronization of estrus, through …
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Detection of Progesterone in Cow’s Milk for the Prediction of Reproductive Performance
Reproductive management is important for the profitability of dairy farms. The correct detection of estrus plays an important role in the success of insemination, conception and further reproductive outcomes. Conventional methods to detect estrus are often laborious or erroneous. Progesterone (P4) …
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Factors affecting the quality and function of the bovine periovulatory follicle
For many cattle operations, profitability depends on the success of reproductive management programs. Opportunities for improving fertility exist within the numerous challenges related to reproductive management. Non-conventional, creative tools for reproductive management could help producers …
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Effects of Differences in Dietary Protein and Varying the Interval from Collection of Bovine Embryos to Freezing on Embryo Quality and Viability
High levels of dietary protein may be detrimental to reproductive performance in cattle. The objective of Exp. 1 was to determine the effects of differences in dietary protein on the production and quality of bovine embryos collected from superovulated donors. Angus cows were randomly assigned to …