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Cattlemen's Day

1990

Articles 1 - 30 of 42

Full-Text Articles in Life Sciences

Calves Delay Estrus Cycles In Postpartum Cows By Mechanisms Other Than Suckling, S.D. Viker, G.H. Kiracofe Jan 1990

Calves Delay Estrus Cycles In Postpartum Cows By Mechanisms Other Than Suckling, S.D. Viker, G.H. Kiracofe

Kansas Agricultural Experiment Station Research Reports

It is generally accepted that the suckling stimulus and the interactions between lactation and level of nutrition regulate the interval from calving to cycling in beef cows. However, rnastectomized cows (udder removed) kept with their calves had longer postpartum intervals to ovulation and estrus than mastectomized cows without calves. We conclude that ovulation and estrus can be suppressed by some cow-calf interaction that is independent of lactation and suckling.


Dose Response To Supplemental Fat By Finishing Steers, S.M. Gramlich, Robert T. Brandt Jr., Ronald V. Pope Jan 1990

Dose Response To Supplemental Fat By Finishing Steers, S.M. Gramlich, Robert T. Brandt Jr., Ronald V. Pope

Kansas Agricultural Experiment Station Research Reports

A trial with 100 head of crossbred steers (avg wt 879 lb) was conducted to determine the effects of tallow (none, 2, 4, 6, 8% of ration dry matter) on the performance and carcass characteristics of finishing cattle fed a corn-based diet. Protein levels were maintained at a constant ratio to the calculated metabolizable energy concentration of the diets. Initially, feed intake decreased as tallow increased; however, similar intakes were obtained after 11 days. Dry matter intakes throughout the finishing period were reduced 5.2, 6.9 and 7.7%, respectively, for the 4, 6 and 8% tallow diets. Average ...


Effects Of Amaferm® (Aspergillus Oryzae Fermentation Extract) On Performance And Body Temperature Of Stockers Fed Diets With Or Without Fescue Endophyte, K.P. Coffey, F.K. Brazle, Joseph L. Moyer Jan 1990

Effects Of Amaferm® (Aspergillus Oryzae Fermentation Extract) On Performance And Body Temperature Of Stockers Fed Diets With Or Without Fescue Endophyte, K.P. Coffey, F.K. Brazle, Joseph L. Moyer

Kansas Agricultural Experiment Station Research Reports

Sixty-four stocker steers were offered endophyte-free fescue hay ad libitum, with either bromegrass or high-endophyte fescue seed screenings and supplements with or without Amaferm8 (Aspergillus oryzae fermentation extract). Steers offered bromegrass seed screenings gained faster (P<.01), consumed more feed (P<.01), and converted feed dry matter to gain more efficiently (P<.01) than those fed fescue seed screenings. Amaferm did not affect stocker performance or reduce rectal temperature. Therefore, feeding high-endophyte fescue screenings reduced intake and daily gain, and Amaferm did not offset those effects.


Effect Of Pregnancy On Forage Intake And Utilization In Spring-Calving Beef Heifers Wintered On Flint Hills Range, E.S. Vanzant, R.C. Cochran Jan 1990

Effect Of Pregnancy On Forage Intake And Utilization In Spring-Calving Beef Heifers Wintered On Flint Hills Range, E.S. Vanzant, R.C. Cochran

Kansas Agricultural Experiment Station Research Reports

Six ruminally and eight bi-fistulated (ruminal and esophageal), 2-yr-old beef heifers were used to study the effects of pregnancy on forage intake and utilization under grazing conditions. During the third trimester of gestation, pregnant heifers ate more (P<.05) forage than nonpregnant heifers and maintained similar (P>.10) levels of organic matter and fiber digestibility. As calving neared, pregnant animals had higher (P<.05) rates of passage and tended to have lower ruminal capacity "¢(P=.15) and digesta fill (P=.14) than nonpregnant animals. Differences in quality of diet selected by the two groups were minimal.


Fat Source Effects On Finishing Steer Digestion And Metabolism, B.J. Bock, D.L. Harmon, Robert T. Brandt Jr., J.E. Schneider Jan 1990

Fat Source Effects On Finishing Steer Digestion And Metabolism, B.J. Bock, D.L. Harmon, Robert T. Brandt Jr., J.E. Schneider

Kansas Agricultural Experiment Station Research Reports

A replicated 3 x 3 Latin square design was used to explore the effects of fat source (none vs 3.5% soybean oil soapstock or animal tallow) when fed with high (1.0%) calcium on digestion and metabolism of a finishing diet by steers. Adding fat did not affect site or extent of starch or dry matter digestion. A net synthesis of long chain fatty acids occurred in the rumen. Feeding fat tended (P=.ll) to depress bacterial N flowing at the duodenum but did not affect nonbacterial N or total N.


Utilization Of Steam-Flaked Milo Or Corn And Supplemental Fat By Finishing Steers, Robert T. Brandt Jr., Gerry L. Kuhl, A.S. Freeman, Curtis L. Kastner Jan 1990

Utilization Of Steam-Flaked Milo Or Corn And Supplemental Fat By Finishing Steers, Robert T. Brandt Jr., Gerry L. Kuhl, A.S. Freeman, Curtis L. Kastner

Kansas Agricultural Experiment Station Research Reports

One hundred forty crossbred yearling steers (815 lb) were utilized to evaluate grain type (steam flaked com vs steam flaked milo) and supplemental fat (O or 4% yellow grease) on finishing performance. There were no differences in carcass-adjusted average daily gain, feed intake, or feed conversion between steers fed milo vs com. Calculated NEtn and NEg contents of flaked milo were approximately 99% those of flaked com and 15 to 20% greater than those of dry rolled milo (NRC, 1984). Supplemental yellow grease increased (P=.12) average daily gain 4.4% and improved (P<.05) feed efficiency 6%. There were no grain type x fat interactions for any performance parameter measured. Steers fed milo had smaller (P<.05) ribeye areas and tended to have more baclcfat and internal (KPH) fat than com-fed steers. As a result, milo-fed steers had a higher (P<.OOI) yield grade. Steers fed com had a higher (P<.OOI) degree of yellow pigmentation in external fat than those fed milo. Supplemental yellow grease resulted in an additive increase (P<.025) in yellow pigmentation. There were no differences in peak shear force or sensory traits of beef longissimus muscle as a result of either grain type or fat level. Our data indicate that steam flaking can increase the net energy value of milo to nearly that of flaked com, with no detrimental effects on the quality of beef produced.


Influence Of Fat And Ionophores On Performance Of Finishing Steers, E.M. Clary, Robert T. Brandt Jr., Ronald V. Pope Jan 1990

Influence Of Fat And Ionophores On Performance Of Finishing Steers, E.M. Clary, Robert T. Brandt Jr., Ronald V. Pope

Kansas Agricultural Experiment Station Research Reports

One hundred ninety-two crossbred steers were used in a 2 x 4 factorially arranged experiment to study the effects of including fat and ionophores in finishing rations. Main effects were level of supplemental fat (0 or 4% tallow) and ionophore type [none, Bovatece (B), Rumensine + 'JYlane (RT), or daily rotation of Band RT (BRT)]. Daily feed intake (P<.10) and daily gain (P<.OO5) were reduced for steers fed R'T, but only when fat was included in the diet. In diets containing no supplemental fat, RT increased daily gain 10%. RT improved feed efficiency 8% (P<.05) in nonfat diets, but there was no difference between ionophores in diets containing fat. Adding fat improved feed efficiency of steers fed no ionophore or B. This study suggests that response of finishing steers to ionophores can be modified by the inclusion of fat in the diet.


Effect Of Fats And Ionophores On In Vitro Fermentation Of A High Concentrate Diet, E.M. Clary, Robert T. Brandt Jr., Tiruvoor G. Nagaraja Jan 1990

Effect Of Fats And Ionophores On In Vitro Fermentation Of A High Concentrate Diet, E.M. Clary, Robert T. Brandt Jr., Tiruvoor G. Nagaraja

Kansas Agricultural Experiment Station Research Reports

Batch culture fermentations were used to determine the effects of fat type [none, animal tallow (AT), soybean oil soapstock (SOY), or yellow grease (YG)] and ionophore type [none, lasalocid (L), monensin + tylosin in a ratio of 2.5:1 (MT), or a 50:50 combination of Land MT (LMT)] on in vitro concentrations of lactate (LA) and volatile fatty acids (VFA). Fat-containing substrates had 4% fat on a dry basis. No significant interactions between fat and ionophore treatments were observed. Ionophore treatment resulted in a reduced pH, with the greatest reduction in the L treatment. lbtal VFA and LA increased ...


Moderation Of Ruminal Fermentation By Protozoa In Cattle Fed High-Grain Diets, G. Towne, A.B. Beharka, Tiruvoor G. Nagaraja Jan 1990

Moderation Of Ruminal Fermentation By Protozoa In Cattle Fed High-Grain Diets, G. Towne, A.B. Beharka, Tiruvoor G. Nagaraja

Kansas Agricultural Experiment Station Research Reports

Ruminal protozoa in cattle fed high-grain diets appear to contribute to the maintenance of a stable ruminal fermentation. This was evidenced by higher ruminal pH's and lower volatile fatty acid concentrations in faunated (with protozoa) than defaunated (without protozoa) cattle. The moderation of fermentation was likely due to reduced bacterial numbers associated with the presence of protozoa.


Influence Of Ruminal Butyrate Supply On Net Nutrient Producti0n And Absorption In Steers, C.R. Krehbiel, D.L. Harmon, J.E. Schneider Jan 1990

Influence Of Ruminal Butyrate Supply On Net Nutrient Producti0n And Absorption In Steers, C.R. Krehbiel, D.L. Harmon, J.E. Schneider

Kansas Agricultural Experiment Station Research Reports

Six Holstein steers were used to evaluate the effects of increasing ruminal butyrate on net nutrient production and absorption by the gastrointestinal tract and liver. Ruminal and arterial concentrations and net hepatic flux of butyrate increased with increasing butyrate infusion. Concentrations of glucose and a-amino-N in arterial blood decreased as butyrate infusion increased. Of the ruminal butyrate infused, 24.5% appeared in portal blood as butyrate. Acetoacetate, D-β-hydroxybutyrate, and a-amino-N were the nutrients most altered by increasing ruminal butyrate.


Value Of Ralgro® Implants In Feedlot Steers Previously Maintained On At High Endophyte-Infected Fescue Hay, L.R. Corah, F.K. Brazle, Frank Blecha, P.G. Reddy, R.E. Jr. Wary, J. Klindt Jan 1990

Value Of Ralgro® Implants In Feedlot Steers Previously Maintained On At High Endophyte-Infected Fescue Hay, L.R. Corah, F.K. Brazle, Frank Blecha, P.G. Reddy, R.E. Jr. Wary, J. Klindt

Kansas Agricultural Experiment Station Research Reports

Steers previously fed high-endophyte fescue hay showed a greater response of Ralgro® implants than those fed a low-endophyte hay. The mode of action for this response was not explained by cellular immune system responses or variability in prolactin levels.


Value Of Rice Mill Feed As A Feedstuff For Backgrounding Heifers, F.K. Brazle, K.P. Coffey Jan 1990

Value Of Rice Mill Feed As A Feedstuff For Backgrounding Heifers, F.K. Brazle, K.P. Coffey

Kansas Agricultural Experiment Station Research Reports

Stocker heifers were fed diets of either 67% rice mill feed + 33 % dehydrated alfalfa pellets (RA) or a 67% grain sorghum + 33% dehydrated alfalfa pellets (GA). The RA heifers consumed more feed daily but gained slower (P<.05), resulting in poorer feed efficiency. RA heifers also had a lower percentage shrink (P<.05) during the first 2 1/2 hr of simulated trucking. Rice mill feed is a poor feedstuff for growing calves when included in rations at high levels.


Aspirated Oat Liftings For Growing Calves, Robert T. Brandt Jr., Gerry L. Kuhl, F.K. Brazle, L.R. Corah, Ronald V. Pope Jan 1990

Aspirated Oat Liftings For Growing Calves, Robert T. Brandt Jr., Gerry L. Kuhl, F.K. Brazle, L.R. Corah, Ronald V. Pope

Kansas Agricultural Experiment Station Research Reports

Feed value of aspirated oat liftings (AOL), a by-product of the oat milling industry, was evaluated by using it to replace 33, 67, or 100% of 36 lb/bu oats in a growing diet fed to heifers. Ammonia treatment of AOL was also tested. Dry matter intake and feed/gain increased linearly (P<.10) with increased AOL. Daily gains were similar for 33, 67, and 100% AOL inclusions, which were lower (P<.01) than the control (0% AOL). Despite lower performance, cheaper costs of production may be achieved with AOL depending on its price relative to other feedstuffs. Ammonia treatment of AOL had no beneficial effect on heifer performance in this study.


Performance Of Steers Limit-Fed In Drylot Or On Mature Native Pasture, F.K. Brazle, Gerry L. Kuhl Jan 1990

Performance Of Steers Limit-Fed In Drylot Or On Mature Native Pasture, F.K. Brazle, Gerry L. Kuhl

Kansas Agricultural Experiment Station Research Reports

Growing steers were limit-fed the same amount of a grain- and silage-based ration either in drylot or on dormant native range. The steers wintered on pasture gained 14.2% slower (1.82 V5 2.08 lb/d; P<.01) and were 15.3% less efficient than those in drylot, apparently because of increased energy expenditure from voluntary exercise.


Leukotoxin Production By Fusobacterium Necrophorum Biotypes, Z. Tan, M. M. Chengappa, Tiruvoor G. Nagaraja Jan 1990

Leukotoxin Production By Fusobacterium Necrophorum Biotypes, Z. Tan, M. M. Chengappa, Tiruvoor G. Nagaraja

Kansas Agricultural Experiment Station Research Reports

Fusobacterium necrophorum biotypes A and B were grown anaerobically to detect their leukotoxin production. Both biotypes exerted the highest leukotoxic effect on bovine leukocytes in the late logarithmic and early stationary growth places. Biotype A produced more leukotoxin than biotype B throughout all phases of bacterial growth. Results are consistent with the findings that biotype A is more virulent than biotype B.


Evaluation Of Attributes Affecting Tenderness Differences Between Bos Taurus And Bos Indicus Cattle, G. Whipple, M. Koohmaraie, J.D. Crouse, Melvin C. Hunt, R.D. Klemm, Michael E. Dikeman Jan 1990

Evaluation Of Attributes Affecting Tenderness Differences Between Bos Taurus And Bos Indicus Cattle, G. Whipple, M. Koohmaraie, J.D. Crouse, Melvin C. Hunt, R.D. Klemm, Michael E. Dikeman

Kansas Agricultural Experiment Station Research Reports

Biological tenderness differences between longissimus muscles from 3/8 and 5/8 Sahiwal (Bos indicus) x Hereford-Angus and from Hereford-Angus (Bos taurus) were evaluated. No significant breed cross effects were observed for carcass traits or rates of pH and temperature decline. Loin steaks from Hereford x Angus had lower (P<.05) shear-force values and higher (P<.05) taste panel tenderness scores at 1 and 14 d postmortem. No breed effects existed for muscle fiber sarcomere length, muscle fiber type, muscle collagen, cathepsin enzyme activity, or calcium-dependent protease-I and -II activity. However, calcium-dependent protease inhibitor activity at 24 hr postmortem was greater (P<.01) in Sahiwal-crosses than for Hereford-Angus. Less protein degradation, which causes tenderization during aging, occurred in Sahiwal-crosses by d 14 than in Hereford-Angus at d 1 postmortem. Therefore, mechanisms involving calcium-dependent protease and its inhibitor may be the principal factors causing tenderness differences between Bos indicus and Bos taurus breeds.


Predicting Beef Carcass Retail Yield From Hot Carcass Traits, J.K. Apple, L.V. Cundiff, J.W. Wise, Michael E. Dikeman Jan 1990

Predicting Beef Carcass Retail Yield From Hot Carcass Traits, J.K. Apple, L.V. Cundiff, J.W. Wise, Michael E. Dikeman

Kansas Agricultural Experiment Station Research Reports

Hot carcasses from 288 steers were used to develop equations to predict weights and percentages of trimmed retail cuts. and trimmable fat yields from hot carcass traits. Independent variables examined were: (1) 12-13th rib fat probe; (2) lO-11th rib fat probe; (3) external fat score; (4) percent kidney knob; (5) hindquarter muscling score, and (6) carcass weight. Right sides of carcasses were fabricated into boneless cuts trimmed to .3 in. fat and weighed. Then. cuts were totally trimmed (.0 in.) and reweighed. Multiple regression equations developed from these variables accounted for 95 and 90% of the variation in total weight ...


Effects Of Finaplix® Synovex-S®, And Ralgro® Implants, Singularly Or In Combinations, On Performance, Carcass Traits, And Longissimus Palatability Of Holstein Steers, J.K. Apple, D.D. Simms, Gerry L. Kuhl, Michael E. Dikeman, Curtis L. Kastner Jan 1990

Effects Of Finaplix® Synovex-S®, And Ralgro® Implants, Singularly Or In Combinations, On Performance, Carcass Traits, And Longissimus Palatability Of Holstein Steers, J.K. Apple, D.D. Simms, Gerry L. Kuhl, Michael E. Dikeman, Curtis L. Kastner

Kansas Agricultural Experiment Station Research Reports

Over the entire feeding period (249 d). Finaplix® (F) plus Synovex-S® (S)-implanted steers had higher (P<.05) daily gains than F+Ralgro® (R), F; and control (C) steers. All treatments produced higher (P<.05) daily gains than C. with the exception of F: The only feed efficiency differences were during the fourth implant period. when F steers were more (P<.05) efficient than F+R or C steers. The F+S and F+R steers had higher (P<.05) masculinity scores than Sand C steers. Carcasses of F +S steers were heavier (P<.05) than those of F and C steers. The F+S steers had larger (P<.05) ribeyes than R, F; and C steers. Also, F+S steers tended (P=.07) to have lower yield grades than S, R. or C steers. Even though marbling scores and quality grades were similar (P>.05) among treatments. only 50% of F+S carcasses graded low Choice or higher compared to a range of 75 to 100% for the other treatments. The only meat palatability differences were tenderness scores; steaks from Sand F + R steers were less tender (P<.07) than those from Rand C steers.


Effects Of Processing Variables On Iridescence In Precooked Beef, H. Wang, Donald H. Kropf, Melvin C. Hunt, Curtis L. Kastner Jan 1990

Effects Of Processing Variables On Iridescence In Precooked Beef, H. Wang, Donald H. Kropf, Melvin C. Hunt, Curtis L. Kastner

Kansas Agricultural Experiment Station Research Reports

Beef semitendinosus (ST) muscles with injected water (3 or 10% of raw muscle weight) and phosphate (0.3%) were cooked to final internal temperatures of 130 (held at 130 for 121 min), 140 (held at 140 for 12 min), 145, or 155°1\ then sliced at 30, 45, 120, 130, or 145<>P by either a dull or a sharp slicer. Biceps femoris (BF) muscles had the same treatment but only at 3% water addition. Controls were uninjected muscles from the opposite side of the carcass. For ST muscles (all with 0.3% added phosphate), 3% added water resulted in ...


Comparison Of Steer Feedlot Performance And Carcass Trait Uniformly By Method Of Sorting, P.L. Houghton, D.D. Simms, James J. Higgins Jan 1990

Comparison Of Steer Feedlot Performance And Carcass Trait Uniformly By Method Of Sorting, P.L. Houghton, D.D. Simms, James J. Higgins

Kansas Agricultural Experiment Station Research Reports

Long yearling steers (n=997) of various biological types from two origins were used to test performance and carcass trait uniformity of unsorted cattle, visually sorted cattle, and cattle sorted by ultrasound and hip height. No significant differences (P> .05) in initial backfat uniformity were identified between sorted and unsorted groups; however, very little variation existed across all treatments (.17±.033 in.). Initial backfat had positive linear relationships with initial weight and carcass backfat and negative linear relationships with days on feed and daily gain (P<.05). These data indicate a reliable measurement of initial backfat could be useful for predicting days on feed and/or carcass backfat in long yearling steers, but economic usefulness will depend upon the variability of the cattle and the method of grouping.


Effect Of Inoculant And Enzyme Additives On Preservation And Nutritive Value Of Alfalfa Silage, J.S. White, K.K. Bolsen, R.A. Hart Jan 1990

Effect Of Inoculant And Enzyme Additives On Preservation And Nutritive Value Of Alfalfa Silage, J.S. White, K.K. Bolsen, R.A. Hart

Kansas Agricultural Experiment Station Research Reports

Lactic acid bacteria (LAB) inoculants and several enzyme additives were evaluated in various combinations using fifth cutting alfalfa. The field-wilted crop was characterized by a high buffer capacity (63.0 meq/100g of DM), low fermentable carbohydrate (5.4% of the DM), and a high number of indigenous LAB (over one million per g). In contrast to several previous studies, the inoculants and enzymes had very little effect on rate and efficiency of fermentation. The 90-d treated silages had similar fiber and digestibility values, compared to the control. Treated silages tended to have higher lactic acid values, but all silages ...


An Evaluation Of Seven Pioneer Corn Hybrids For Silage And A Comparison Of Irrigated Vs Dryland Silages, D.G. Tiemann, K.K. Bolsen, R. Suazo, D. Johnson Jan 1990

An Evaluation Of Seven Pioneer Corn Hybrids For Silage And A Comparison Of Irrigated Vs Dryland Silages, D.G. Tiemann, K.K. Bolsen, R. Suazo, D. Johnson

Kansas Agricultural Experiment Station Research Reports

Seven Pioneer corn hybrids and one grain sorghum hybrid were grown under both irrigated and dryland conditions in 1988 and compared for agronomic and silage quality traits. Com hybrid silage yields ranged from 4.5 to 7.6 tons of dry matter (OM) per acre (mean, 5.8 tons) and grain yield, from 64 to 115 bu per acre (mean, 87 bu). Pre-ensiled DM content of the corn hybrids ranged from 26.7 to 33.0% (mean, 29.5%) and plant height from 82 to 108 in. (mean, 94 in.). In a digestion trial with sheep, apparent DM digestibility ranged ...


Characteristics Of The Indigenous Microflora From Five Silage Crops In 1987, R.A. Hart, F. Niroomand, K.K. Bolsen, M.A. Lubinski, W.R. Aimutis Jan 1990

Characteristics Of The Indigenous Microflora From Five Silage Crops In 1987, R.A. Hart, F. Niroomand, K.K. Bolsen, M.A. Lubinski, W.R. Aimutis

Kansas Agricultural Experiment Station Research Reports

Indigenous lactic acid bacteria (LAB) were isolated from five silage crops in the 1987 growing season: wheat, alfalfa, com, interseeded grain sorghum and soybeans, and forage sorghum. All crops had post-harvest LAB counts that exceeded 5 x 105 colony-forming units/g. There were no significant correlations between rate of fermentation during the first 7 d post-ensiling and the indigenous LAB counts. However, corn and sorghum, which fermented rapidly, had higher populations of homofermentative LAB, and the isolates showed higher rod to cocci ratios compared to the other three crops. Most of the homofermentative rods isolated were Lactobacillus plantarum, and most ...


Preliminary Carcass And Meat Research Results From Cycle Iv Of The Cattle Germ Plasm Evaluation Program, L.V. Cundiff, R.M. Koch, K.E. Gregory, J.D. Crouse, Michael E. Dikeman Jan 1990

Preliminary Carcass And Meat Research Results From Cycle Iv Of The Cattle Germ Plasm Evaluation Program, L.V. Cundiff, R.M. Koch, K.E. Gregory, J.D. Crouse, Michael E. Dikeman

Kansas Agricultural Experiment Station Research Reports

Preliminary data representing two of five calf crops in Cycle IV of the Germ Plasm Evaluation Program are reported. Carcass and meat data from 454 steers produced by mating 11 sire breeds to Hereford and Angus dams were obtained. Hereford (H) and Angus (A) sires born in the late 1960's (original) and also 1982 to 1984 (new) were compared. Steers sired by the new sample of H and A sires were heavier at slaughter than those of original sires, whereas marbling and percentages of trimmed retail product (% TRP) have not changed. HA and AH had lower % TRP than most ...


Effects Of Rumen-Escape Lipid In A Range Supplement On Postpartum Reproductive Function In Beef Cows, R.B. Hightshoe, R.C. Cochran, L.R. Corah, D.L. Harmon, G.H. Kiracofe Jan 1990

Effects Of Rumen-Escape Lipid In A Range Supplement On Postpartum Reproductive Function In Beef Cows, R.B. Hightshoe, R.C. Cochran, L.R. Corah, D.L. Harmon, G.H. Kiracofe

Kansas Agricultural Experiment Station Research Reports

Postpartum cows receiving a range supplement containing rumen-escape lipid exhibited altered hormone and cholesterol levels compared to cows not fed lipid. Sixty-seven percent of lipid-fed cows exhibited a normal (18.2 d) first estrous cycle vs 33% for cows not receiving lipid. Incorporation of rumen-escape lipid into range supplements appears to significantly improve postpartum reproductive characteristics.


Effects Of Dietary Energy On Reproductive Function And Production In Suckled Beef Cows, R.C. Perry, L.R. Corah, W.E. Beal, G.H. Kiracofe, R.C. Cochran, D.D. Simms, J.R. Brethour, Jeffrey S. Stevenson Jan 1990

Effects Of Dietary Energy On Reproductive Function And Production In Suckled Beef Cows, R.C. Perry, L.R. Corah, W.E. Beal, G.H. Kiracofe, R.C. Cochran, D.D. Simms, J.R. Brethour, Jeffrey S. Stevenson

Kansas Agricultural Experiment Station Research Reports

Twenty-eight Hereford x Angus cows were utilized to determine the effects of dietary energy level before and after calving on reproductive function and production in suckled beef cows. Low levels of dietary energy before calving resulted in losses of body composition prior to calving, reduced calf birth weight, lengthened intervals from calving to ovulation, and decreased milk production and calf weight at 70 d of age (P<.05). Low levels of dietary energy after calving decreased measures of body composition after calving, reduced the percentage of cows that ovulated following calving, and decreased cow milk production and calf weight at 70 d of age (P< .05). We conclude that dietary energy before and after calving impacts the reproductive function and production of suckled beef cows.


Diagnosis Of Freemartinism In Heifers Born Co-Twin To A Bull, B.L. Larson, G.H. Kiracofe Jan 1990

Diagnosis Of Freemartinism In Heifers Born Co-Twin To A Bull, B.L. Larson, G.H. Kiracofe

Kansas Agricultural Experiment Station Research Reports

The wide variance in anatomical characteristics among heifers born co-twin to a bull make diagnosis of freemartinism by measurements of vaginal length or the distance between the anus and vulva unreliable. Change in serum luteinizing hormone (LH) in response to injection of estrogen or gonadotropin releasing hormone (GnRH) is different in freemartins compared to normal heifers but is also an unreliable predictor of freemartinism. Presently, the most conclusive way to establish freemartinism in a heifer born co-twin to a bull is to measure the percentage of XX and XY chromosomes in cells from whole blood, which is a specialized and ...


Cow/Calf Profitability: Case Studies Of Kansas Cattle Producers, D.D. Simms, T.T. Marston Jan 1990

Cow/Calf Profitability: Case Studies Of Kansas Cattle Producers, D.D. Simms, T.T. Marston

Kansas Agricultural Experiment Station Research Reports

Cost/return analyses of 56 Kansas cow/calf operations were summarized to determine the major factors influencing 1987 and 1988 cow herd profitability. Gross returns and costs on a per cow unit basis were extremely variable. with the bottom 1/3 of these operations essentially breaking even. whereas the high 1/3 profitability group averaged $228.40 per head in net cash returns. Both operating and fixed costs were major determinants of profitability. Reproductive rate (calves weaned per cow exposed) was the major production variable affecting profitability.


Seventeen Years Of Kansas Central Bull Tests, R.R. Schalles, B.J. Ward, K.O. Zoellner, L.C. Martin Jan 1990

Seventeen Years Of Kansas Central Bull Tests, R.R. Schalles, B.J. Ward, K.O. Zoellner, L.C. Martin

Kansas Agricultural Experiment Station Research Reports

Weights. frame scores. scrotal circumferences, and prices of bulls increased significantly over 17 years. Angus had the greatest increase in birth weight, average daily gain (ADG) during test, adjusted yearling weight, and frame score, whereas Simmental had the greatest increase in adjusted weaning weight. Backfat and ribeye area decreased over this period. Large frame score had the greatest effect on increasing sale priCe of bulls. Gelbvieh bulls with heavy birth weights sold for less, whereas heavy birth weight Limousin and Polled Hereford bulls sold for more. Rank correlations indicated a significant change in rank between 112- and 140-d ADG. About ...


Managing Beef Genotypes For Profit: A Computer Simulation, R.R. Schalles, L.C. Martin, K.O. Zoellner Jan 1990

Managing Beef Genotypes For Profit: A Computer Simulation, R.R. Schalles, L.C. Martin, K.O. Zoellner

Kansas Agricultural Experiment Station Research Reports

In a computer simulation based on KSU data, cattle bred and managed to be moved directly from weaning to feedlot and slaughtered at a young age produced the greatest profit. Cattle that were too small or too large and management systems that increased age at slaughter were less profitable. This accelerated system of production allows a producer to take advantage of superior genetics and the economic opportunities they provide, especially with retained ownership. The beef industry has the opportunity to continue to produce quality beef, while reducing days to slaughter by taking advantage of the higher efficiency of feed conversion ...