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2018 Swine Day Foreword, Etc., R. D. Goodband Jan 2018

2018 Swine Day Foreword, Etc., R. D. Goodband

Kansas Agricultural Experiment Station Research Reports

It is with great pleasure that we present the 2018 Swine Industry Day Report of Progress. This report contains updates and summaries of applied and basic research conducted at Kansas State University during the past year. We hope that the information will be of benefit as we attempt to meet the needs of the Kansas swine industry.


Physiologic Responses To Feeding Rumen-Protected Glucose To Lactating Dairy Cows, J. A. Sauls-Hiesterman, S. Banuelos, B. Atanasov, B. Bradford, J. S. Stevenson Jan 2018

Physiologic Responses To Feeding Rumen-Protected Glucose To Lactating Dairy Cows, J. A. Sauls-Hiesterman, S. Banuelos, B. Atanasov, B. Bradford, J. S. Stevenson

Kansas Agricultural Experiment Station Research Reports

Lactating Holstein cows were enrolled in a study beginning before first insemina­tion. Cows were supplemented with a rumen-protected glucose (RPG) product to test the hypothesis that circulating progesterone concentrations could be increased by increasing blood glucose, which causes an increase in insulin, subsequently decreasing progesterone clearance by liver enzymes. Supplementation occurred at 0, 2.2, 4.4, or 8.8 lb per head per day to test a dose response. Treatment began 3 days before ovula­tion and continued until day 12 of the estrous cycle. Rumen-protected glucose did not impact serum concentration of glucose before or after feeding, but the change in insulin …


2018 Dairy Research, B. J. Bradford Jan 2018

2018 Dairy Research, B. J. Bradford

Kansas Agricultural Experiment Station Research Reports

Research on dairy foods and dairy cattle performed in 2018 at Kansas State University.


Biological Variability And Chances Of Error Jan 2018

Biological Variability And Chances Of Error

Kansas Agricultural Experiment Station Research Reports

Variability among individual animals in an experiment leads to problems in interpreting the results. Animals on treatment X may have higher average daily gains than those on treatment Y, but variability within treatments may indicate that differences in production between X and Y were not the result of treatment alone. Statistical analysis allows us to calculate the probability that such differences are from treatment rather than chance.


Effects Of Frequency Of Protein Supplementation On Performance By Beef Calves Grazing Dormant Native Range, G. W. Preedy, J. R. Jaeger, J. W. Waggoner, K C. Olson Jan 2018

Effects Of Frequency Of Protein Supplementation On Performance By Beef Calves Grazing Dormant Native Range, G. W. Preedy, J. R. Jaeger, J. W. Waggoner, K C. Olson

Kansas Agricultural Experiment Station Research Reports

Stocker calves that graze forages before entering a feedlot account for more than 75% of the beef calves raised in the United States each year. A large proportion of those will be calves born in the spring and weaned in the fall. Modest growth rates are expected when the quality of fall and winter forages is poor. Growing calves in confinement systems during fall and winter typically allows for greater average daily gain (ADG) than graz­ing low-quality forages; however, modest overall costs associated with grazing perennial, dormant forages may be competitive during times when feed prices are relatively high.

Providing …


Gonadotropin-Releasing Hormone Increased Pregnancy In Suckled Beef Cows Not Detected In Estrus And Subjected To A Split-Time Artificial Insemination Program, S. L. Hill, D. M. Grieger, K C. Olson, J. R. Jaeger, K. R. Harmoney, C. R. Dahlen, M. R. Crosswhite, N. Negrin Pereira, S. R. Underdahl, B. W. Neville, J. Ahola, M. C. Fischer, G E. Seidel, J. Stevenson Jan 2018

Gonadotropin-Releasing Hormone Increased Pregnancy In Suckled Beef Cows Not Detected In Estrus And Subjected To A Split-Time Artificial Insemination Program, S. L. Hill, D. M. Grieger, K C. Olson, J. R. Jaeger, K. R. Harmoney, C. R. Dahlen, M. R. Crosswhite, N. Negrin Pereira, S. R. Underdahl, B. W. Neville, J. Ahola, M. C. Fischer, G E. Seidel, J. Stevenson

Kansas Agricultural Experiment Station Research Reports

Estrus-synchronization programs allow insemination of all females in a herd at one fixed time on the first day of the breeding season. Inseminating cows after they have expressed estrus increases pregnancy rate (PR) compared with cows that do not display estrus in a timed AI (TAI) program. Identification of estrus status can be facilitated by using estrus-detection patches. Varying AI timing according to estrus status has increased PR in some previous studies. Reducing the number of injections in a TAI program decreases labor requirements, stress on cows, and overall cost of the program. Previous studies have demonstrated that PR is …


Agricultural Research Center-Hays, Roundup Jan 2018

Agricultural Research Center-Hays, Roundup

Kansas Agricultural Experiment Station Research Reports

Roundup is the major beef cattle education and outreach event sponsored by the Agricultural Research Center–Hays. The 2018 program is the 104th staging of Roundup. The purpose is to communicate timely, applicable research information to producers and extension personnel.

The research program of the Agricultural Research Center–Hays is dedicated to serving the people of Kansas by developing new knowledge and technology to stabilize and sustain long-term production of food and fiber in a manner consistent with conservation of natural resources, protection of the environment, and assurance of food safety. Primary emphasis is on production efficiency through optimization of inputs in …


Effects Of Various Grazing Systems On Grazing And Subsequent Finishing Performance, L. W. Lomas, J. L. Moyer Jan 2018

Effects Of Various Grazing Systems On Grazing And Subsequent Finishing Performance, L. W. Lomas, J. L. Moyer

Kansas Agricultural Experiment Station Research Reports

MaxQ tall fescue, a wheat-bermudagrass double-crop system, and a wheat-crabgrass double-crop system have been three of the most promising grazing systems evaluated at the Kansas State University Southeast Agricultural Research Center in the past 20 years, but these systems have never been compared directly in the same study. The objective of this study was to compare grazing and subsequent finishing performance of stocker steers that grazed these three systems.


The Livestock And Meat Industry Council, Inc. Jan 2018

The Livestock And Meat Industry Council, Inc.

Kansas Agricultural Experiment Station Research Reports

The Livestock and Meat Industry Council, Inc. (LMIC) is a non-profit charitable organization supporting animal agriculture research, teaching, and education. This is accomplished through the support of individuals and businesses that make LMIC a part of their charitable giving.


Effect Of Draining Volume On The Yield And Enrichment Ratio During Foam Fractionation Of Greek Yogurt Whey, Y. B. Ma, J. Amamcharla Jan 2018

Effect Of Draining Volume On The Yield And Enrichment Ratio During Foam Fractionation Of Greek Yogurt Whey, Y. B. Ma, J. Amamcharla

Kansas Agricultural Experiment Station Research Reports

Foam fractionation was evaluated as a cost-effective method to add value to Greek yogurt whey (GYW), a co-product of Greek yogurt manufacturing. Two separate batches of GYW were obtained from a Greek yogurt manufacturer. Whey proteins present in GYW can be concentrated and manufactured as food ingredients using a low-cost foam fractionation. The objective of this study was to apply foam fractionation with different draining volumes to GYW and evaluate its enrichment and yield of whey protein. A benchtop foam fractionation setup was built in-house, and three different foam draining volumes were used to identify the optimal processing parameters for …


Effects Of Early Or Conventional Weaning On Beef Cow And Calf Performance In Pasture And Drylot Environments, G. W. Preedy, J. R. Jaeger, J. W. Waggoner, K C. Olson, K. R. Harmoney Jan 2018

Effects Of Early Or Conventional Weaning On Beef Cow And Calf Performance In Pasture And Drylot Environments, G. W. Preedy, J. R. Jaeger, J. W. Waggoner, K C. Olson, K. R. Harmoney

Kansas Agricultural Experiment Station Research Reports

During widespread drought, pasture availability and productivity are reduced. This, coupled with increasing land prices and lease rates, has prompted the evaluation of al­ternative management strategies that decrease grazing pressure on perennial pasture or reduce feed and pasture costs. Weaning early and moving cows from pasture to a drylot environment is used commonly for reducing grazing pressure on perennial pastures. A premature end to lactation reduces cow nutrient requirements and reduces grazing pressure. Removal of the calf further reduces grazing pressure, as calves are significant consumers of forage dry matter (DM) during mid and late lactation. The combina­tion can be …


Using Modified Intensive Early Stocking For Grazing Replacement Heifers, K. R. Harmoney, J. R. Jaeger Jan 2018

Using Modified Intensive Early Stocking For Grazing Replacement Heifers, K. R. Harmoney, J. R. Jaeger

Kansas Agricultural Experiment Station Research Reports

Even though Kansas native rangelands often have steep slopes or shallow soils not conducive to many other uses other than livestock grazing, native rangeland and peren­nial grassland acres in Kansas have been declining. Cropland acreage over this same time frame has increased, and so has rangeland fragmentation into small ranchettes and urbanization. Producers may be looking to increase production efficiency on a shrink­ing forage land base. The use of intensive early stocking (IES) is one the most efficient stocking strategies to produce beef on rangeland acres. The IES strategy has been widely used in eastern Kansas and is capable of …


Effects Of Interseeding Ladino Clover Into Tall Fescue Pastures Of Varying Endophyte Status On Grazing Performance Of Stocker Steers, L. W. Lomas, J. L. Moyer Jan 2018

Effects Of Interseeding Ladino Clover Into Tall Fescue Pastures Of Varying Endophyte Status On Grazing Performance Of Stocker Steers, L. W. Lomas, J. L. Moyer

Kansas Agricultural Experiment Station Research Reports

Tall fescue, the most widely adapted cool-season perennial grass in the United States, is grown on approximately 66 million acres. Although tall fescue is well adapted in the eastern half of the country between the temperate north and mild south, presence of a fungal endophyte results in poor performance of grazing livestock, especially during the summer. Until recently, producers with high-endophyte tall fescue pastures had two primary options for improving grazing livestock performance. One option was to destroy existing stands and replace them with endophyte-free fescue or other forages. Although it supports greater animal performance than endophyte-infected fescue, endophyte-free fescue …


Including Legumes In Bermudagrass Pastures, J. L. Moyer, L. W. Lomas Jan 2018

Including Legumes In Bermudagrass Pastures, J. L. Moyer, L. W. Lomas

Kansas Agricultural Experiment Station Research Reports

Bermudagrass is a productive forage species when intensively managed. However, it has periods of dormancy and requires proper management to maintain forage quality. Legumes in the bermudagrass sward could improve forage quality and reduce fertilizer usage; however, legumes are difficult to establish and maintain with the competitive grass. Clovers can maintain survival once established in bermudagrass sod and may be productive enough to substitute for some N fertilization. This study was designed to compare dry cow performance on a bermudagrass pasture system that included ladino and crimson clovers (Legume) vs. bermudagrass alone (Nitrogen).


Can Modified Intensive Early Stocking Be Used In Cow/Calf Production?, K. R. Harmoney, J. R. Jaeger Jan 2018

Can Modified Intensive Early Stocking Be Used In Cow/Calf Production?, K. R. Harmoney, J. R. Jaeger

Kansas Agricultural Experiment Station Research Reports

Intensive early stocking (IES) was introduced nearly a half century ago in eastern Kansas and has since been adopted as a major management tool to increase animal production, efficiency of production, and economic return on tallgrass rangelands. These increases have come almost exclusively by using IES with young stocker animals. Intensive early stocking and its gains have been proven effective repeatedly in published research. A similar modified IES (MIES) system has increased production efficiency of stocker animals on western Kansas rangelands. Perennial grassland acres for cattle production, as well as cattle numbers, are declining. Using management practices that mimic a …


Evaluation Of Different Vitamin Concentrations On Grow-Finish Pig Growth And Carcass Characteristics, L. Del Tuffo, S. S. Dritz, M. D. Tokach, J. C. Woodworth, J. M. Derouchey, R. D. Goodband Jan 2018

Evaluation Of Different Vitamin Concentrations On Grow-Finish Pig Growth And Carcass Characteristics, L. Del Tuffo, S. S. Dritz, M. D. Tokach, J. C. Woodworth, J. M. Derouchey, R. D. Goodband

Kansas Agricultural Experiment Station Research Reports

Vitamins are generally added to swine diets in concentrations well above their requirement estimates to provide a generous margin of safety. However, with the increase in vitamin prices in 2017, there was a need to re-evaluate suggested vitamin additions. Therefore, the objective of this study was to compare two premixes with different vitamin concentrations on growth performance and carcass characteristics of grow-finish pigs reared in a commercial environment. A total of 1,188 pigs (PIC 359 × 1050; initially 35.5 lb) were used in a randomized complete block design with 27 pigs per pen and 22 pens per treatment. The experimental …


2018 Dairy Research Foreword, Etc., B. J. Bradford Jan 2018

2018 Dairy Research Foreword, Etc., B. J. Bradford

Kansas Agricultural Experiment Station Research Reports

Kansas State University is pleased to present the 2018 Dairy Research Report of Progress and proud to serve the growing Kansas dairy industry.


Searc Agricultural Research 2018, L. W. Lomas Jan 2018

Searc Agricultural Research 2018, L. W. Lomas

Kansas Agricultural Experiment Station Research Reports

Agricultural Research 2018, Southeast Agricultural Research Center, Kansas State University, April 2018


Cattlemen's Day 2018, E. A. Boyle Jan 2018

Cattlemen's Day 2018, E. A. Boyle

Kansas Agricultural Experiment Station Research Reports

Full report, Cattlemen's Day 2018.


Interseeding Warm-Season Annual Grasses Into Perennial Cool-Season Western Wheatgrass Pasture, K. R. Harmoney, J. Guretzky Jan 2018

Interseeding Warm-Season Annual Grasses Into Perennial Cool-Season Western Wheatgrass Pasture, K. R. Harmoney, J. Guretzky

Kansas Agricultural Experiment Station Research Reports

Conversion of pastureland into cropland has occurred at a rapid rate on the central to northern Great Plains. A reduction in total acreage of pastureland from this conversion has resulted in a decline of total numbers of beef cows in the same region. One method to mitigate the decline in cow numbers is to increase carrying capacity of the remaining pastureland acres. Introducing warm-season annual grass species into perennial coolseason grass pastures to increase dry matter production during the mid-summer time period that perennial cool-season grasses would be most dormant is one strategy that may be able to boost production. …


Evaluation Of Supplemental Energy Source For Grazing Stocker Cattle, L. W. Lomas, J. K. Farney, J. L. Moyer Jan 2018

Evaluation Of Supplemental Energy Source For Grazing Stocker Cattle, L. W. Lomas, J. K. Farney, J. L. Moyer

Kansas Agricultural Experiment Station Research Reports

Supplementation of grazing cattle is most economically feasible when cattle prices are high relative to the price of grain. Energy supplementation of grazing ruminants may reduce forage intake and digestibility, but energy supplementation at low levels (less than 0.4% bodyweight) has been shown to have little effect on forage intake when crude protein was not limiting. Several studies have evaluated the effect of supplementation on stocker cattle gains and forage utilization during the grazing phase, but few have evaluated the effects of supplementation during the grazing phase on subsequent finishing performance and carcass traits. This research seeks to obtain a …


Development Of A High Protein Dairy Snack Based On German-Style Quark Cheese, Y. Ou, K. S. Babu, P. Thorakkattu, K. Getty, J. Amamcharla Jan 2018

Development Of A High Protein Dairy Snack Based On German-Style Quark Cheese, Y. Ou, K. S. Babu, P. Thorakkattu, K. Getty, J. Amamcharla

Kansas Agricultural Experiment Station Research Reports

Current consumer trends highlight the need for developing convenient and ready-to-eat snack foods that render health benefits when consumed. Rising popularity of protein-enriched foods and beverages have led to increasing awareness among consumers of health benefits related to a dairy-rich diet. The vast majority of people have adopted this lifestyle, spotting the protein’s importance in delivering vital nutrients for health and maintenance of the body, curbing hunger, sustaining a slow release of energy, and speeding the metabolism. Innovation is the key driver for the dairy snack market. The primary objective of this project was to develop an American-sourced predominantly dairy …


Gestation Length And Overall Performance In The Subsequent Lactation Of Dairy Cows Conceiving To Holstein, Jersey, Or Angus Semen: An Observational Study, A. L. Scanavez, L. G. Mendonça Jan 2018

Gestation Length And Overall Performance In The Subsequent Lactation Of Dairy Cows Conceiving To Holstein, Jersey, Or Angus Semen: An Observational Study, A. L. Scanavez, L. G. Mendonça

Kansas Agricultural Experiment Station Research Reports

Breeding strategies adopted by commercial dairy herds have evolved in recent years by incorporating the use of several breeds, including beef sires. Results of such strategies on offspring performance have been studied but reports on the effects on dam’s overall performance after calving are still lacking. The goal of this observational study was to investigate the associations between sire breed of previous conception, gestation length, and postpartum performance of dairy cows. Records from Holstein and crossbred cows from a Kansas commercial herd were extracted. Data pertaining to cows that conceived from Holstein, Jersey, or Angus sires and initiated second lactation …


Effects Of Supplementation With Corn Or Dried Distillers Grains On Gains Of Heifer Calves Grazing Smooth Bromegrass Pastures, L. W. Lomas, J. L. Moyer Jan 2018

Effects Of Supplementation With Corn Or Dried Distillers Grains On Gains Of Heifer Calves Grazing Smooth Bromegrass Pastures, L. W. Lomas, J. L. Moyer

Kansas Agricultural Experiment Station Research Reports

Distillers grains, a by-product of the ethanol industry, have tremendous potential as an economical and nutritious supplement for grazing cattle. Distillers grains contain a high concentration of protein (25 to 30%), with more than two-thirds escaping degradation in the rumen, which makes it an excellent supplement for younger cattle. Recent advancements in the ethanol manufacturing process have resulted in extraction of a greater amount of fat; therefore, creating distillers grains that may contain less energy than corn. This research was conducted to compare performance of stocker cattle supplemented with corn or DDG at 0.5% body weight per head daily while …


The Effect Of Phase-Feeding Strategies On Growth Performance And Carcass Characteristics Of Growing-Finishing Pigs: I. Lysine Levels At The Estimated Requirement, M. B. Menegat, S. S. Dritz, M. D. Tokach, J. C. Woodworth, J. M. Derouchey, R. D. Goodband Jan 2018

The Effect Of Phase-Feeding Strategies On Growth Performance And Carcass Characteristics Of Growing-Finishing Pigs: I. Lysine Levels At The Estimated Requirement, M. B. Menegat, S. S. Dritz, M. D. Tokach, J. C. Woodworth, J. M. Derouchey, R. D. Goodband

Kansas Agricultural Experiment Station Research Reports

The objective of this study was to evaluate phase-feeding strategies for grow-finish pigs under commercial research conditions and using lysine levels closely set to the pig’s requirement estimates for maximum growth performance. A total of 1,188 pigs (PIC 359 × 1050; initially 60.4 lb body weight (BW)) were used in a randomized complete block design with 27 pigs per pen and 11 pens per treatment. Treatments consisted of four feeding programs: a 1-phase feeding program with 0.82% standardized ileal digestible (SID) lysine from 60 to 280 lb BW; a 2-phase feeding program with 0.96 and 0.77% SID lysine from 60 …


Effects Of Increasing Oat Groats On Nursery Pig Performance, J. A. Chance, A. B. Lerner, J. M. Derouchey, J. C. Woodworth, M. D. Tokach, R. D. Goodband, S. S. Dritz Jan 2018

Effects Of Increasing Oat Groats On Nursery Pig Performance, J. A. Chance, A. B. Lerner, J. M. Derouchey, J. C. Woodworth, M. D. Tokach, R. D. Goodband, S. S. Dritz

Kansas Agricultural Experiment Station Research Reports

In Exp. 1, a total of 225 pigs (241 × 600, DNA, Columbus, NE; initially 13.9 lb BW) were used in a 28-d study to evaluate the effects of increasing ground oat groats on nursery pig growth performance. Pigs were weaned at 21 d of age and randomly allotted to pens and fed a commercial starter diet for 7 d prior to the start of the experiment. Pens of pigs were assigned to 1 of 5 dietary treatments in a randomized complete block design by body weight (BW) with 4 or 5 pigs per pen and 10 pens per treatment. …


Evaluation Of The Effects Of High-Lysine Sorghum On Nursery Pig Performance, L. L. Thomas, R. D. Goodband, C. D. Espinosa, H. H. Stein, J. C. Woodworth, M. D. Tokach, S. S. Dritz, J. M. Derouchey Jan 2018

Evaluation Of The Effects Of High-Lysine Sorghum On Nursery Pig Performance, L. L. Thomas, R. D. Goodband, C. D. Espinosa, H. H. Stein, J. C. Woodworth, M. D. Tokach, S. S. Dritz, J. M. Derouchey

Kansas Agricultural Experiment Station Research Reports

Two experiments were conducted to determine the standardized ileal digestibility (SID) of amino acids in a high-lysine sorghum cultivar, followed by a growth trial to determine the effect of this sorghum on pig performance using increasing additions of feed-grade amino acids at the expense of soybean meal. In Exp. 1, ten growing barrows (initially 57.1 lb; Line 359 × 1050; PIC, Hendersonville, TN) were surgically fitted with a T-cannula at the terminal ileum and randomly assigned to 1 of 5 test diets in a 5-period, cross-over design. Experimental diets consisted of a corn-based diet, a diet containing high-lysine sorghum, or …


Marbling Texture Has No Effect On Collagen Characteristics, B. A. Olson, K. R. Vierck, J. M. Gonzalez, J. A. Noel, T. A. Houser, E. A. Boyle, T. G. O'Quinn Jan 2018

Marbling Texture Has No Effect On Collagen Characteristics, B. A. Olson, K. R. Vierck, J. M. Gonzalez, J. A. Noel, T. A. Houser, E. A. Boyle, T. G. O'Quinn

Kansas Agricultural Experiment Station Research Reports

Objective:The objective of this study was to determine the effects of marbling texture on collagen traits and adipocyte cross-sectional area.

Study Description:Beef strip loins (n = 117) from three U.S. Department of Agriculture quality grades (Top Choice, Low Choice, and Select) with three marbling textures (fine, medium, and coarse) were selected using visual appraisal. Strip loins were taken to the Kansas State University meat laboratory, Manhattan, KS, fabricated into 1-in steaks, vacuum packaged, and aged for 21 days at 40°F. Following aging, steaks were analyzed for collagen and adipocyte staining, imaging, and peak thermal transition temperature.

The Bottom …


Effects Of Dietary Corn Dried Distillers Grains With Solubles Withdrawal On Finishing Pig Performance And Carcass Characteristics, A. B. Lerner, M. D. Tokach, J. C. Woodworth, J. M. Derouchey, S. S. Dritz, R. D. Goodband, C. Hastad, K. Coble, E. Arkfeld, H. C. Cartagena, C. Vahl Jan 2018

Effects Of Dietary Corn Dried Distillers Grains With Solubles Withdrawal On Finishing Pig Performance And Carcass Characteristics, A. B. Lerner, M. D. Tokach, J. C. Woodworth, J. M. Derouchey, S. S. Dritz, R. D. Goodband, C. Hastad, K. Coble, E. Arkfeld, H. C. Cartagena, C. Vahl

Kansas Agricultural Experiment Station Research Reports

Two experiments were conducted to evaluate the effects of removing corn dried distillers grains with solubles (DDGS) at increasing intervals before harvest on finishing pig performance and carcass characteristics. For Exp. 1, 985 finishing pigs [initially 219 ± 5.5 lb body weight (BW)] were used in a 28-d growth study. There were 12 pens per treatment with 19 to 21 pigs per pen. There were four treatments decreasing in duration of withdrawal of DDGS from diets before final marketing: 28, 21, 14, or 0 d withdrawal. Regardless of treatment, pens of pigs were topped according to a typical summer marketing …


Two Split-Time Artificial Insemination Programs In Suckled Beef Cows, J. Stevenson, S. L. Hill, D. M. Grieger, K C. Olson, J. R. Jaeger, K. R. Harmoney, J. Ahola, G. E. Seidel, R. K. Kasimanickam Jan 2018

Two Split-Time Artificial Insemination Programs In Suckled Beef Cows, J. Stevenson, S. L. Hill, D. M. Grieger, K C. Olson, J. R. Jaeger, K. R. Harmoney, J. Ahola, G. E. Seidel, R. K. Kasimanickam

Kansas Agricultural Experiment Station Research Reports

Successful programs to manipulate estrus and ovulation to maximize pregnancy out­comes in suckled beef cattle have been developed to limit animal handling and to elimi­nate the need to detect estrus, thereby providing more opportunity to incorporate AI to start the breeding season. The most successful and consistent synchronization scheme employs an intravaginal progesterone insert (controlled internal drug release, CIDR) in place for 7 d concurrent with GnRH treatment, and, upon removal of the insert, injection of PGF, followed by timed AI at 60 to 66 h concurrent with a second dose of GnRH (CO-synch + CIDR).

Inseminating cows …