Download or read book Effects of Feeding Perennial Peanut Hay on Growth Development Attainment of Puberty and Fertility in Beef Replacement Heifers written by Kalyn Marie Bischoff and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: The objective of this study was to determine the influence of supplemental feeding of perennial peanut hay (Arachis glabrata Benth.) on growth performance and age at puberty in growing beef cattle heifers. Over a two year period, 120 heifers were randomly allocated into pens and assigned to one of three supplement treatments: 80% corn and 20% soybean meal supplement (CSBM), perennial peanut hay supplementation (PPH), and a control which received no supplement (CON). All heifers received ad libitum access to bermudagrass hay (Cynodon dactylon (L.) Pers.) during the 140-developmental phase. Following the developmental phase, heifers were comingled for a 77 d breeding season during the breeding phase. Period influenced ADG (P = 0.002) and treatment effected ADG, with the CON tending (P = 0.06) to be have lesser ADG than the CSBM and PPH heifers. There was a treatment \U+00d7\ day interaction (P = 0.06) on mean body weight (BW) with heifers in the CON treatment being lighter at the conclusion of the development phase (P = 0.02). Total DMI during the 140-d development phase was greater (P

Download or read book Bovine Theriogenology An Issue of Veterinary Clinics of North America Food Animal Practice E Book written by Robert L. Larson and published by Elsevier Health Sciences. This book was released on 2016-07-10 with total page 305 pages. Available in PDF, EPUB and Kindle. Book excerpt: This issue of Veterinary Clinics of North America: Food Animal Practice focuses on Bovine Theriogenology. Article topics include: Reproductive systems for North American Beef Cattle Herds, Reproductive systems for North American Dairy Cattle Herds, Beef Heifer Development, Dairy Heifer Development, Evaluation of data obtained at pregnancy detection of beef herds ,Synchronization and AI Strategies in Beef Herds, Synchronization and AI Strategies in Dairy Herds, Embryo Transfer, Management of reproductive disease in dairy cattle, Venereal Diseases of Cattle, Diagnosis and Control of Neosporosis, Management and Breeding Soundness Examination of Yearling Bulls, and more!

Download or read book Puberty Development and Reproductive Performance in Beef Heifers Fed Rations Supplemented with Oregon By product Feeds written by Keely E. Oswald and published by . This book was released on 2011 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the majority of management scenarios, it is imperative that beef replacement heifers calve at two years of age. In order to achieve this goal, yearling heifers should reach 60 to 65% of their mature body weight by 13 months of age. Feed costs represent 75 to 80% of the total costs incurred by a beef producer in the development of replacement heifers. At current beef prices, it takes at least three live calves before the heifer development period is paid. Feed costs have become more problematic and volatile in recent years. Increasing pressure for the use of grains in brewing and for ethanol production has inflated feed prices. Demand for grain has also resulted in more ground being taken out of forage production which has resulted in much higher hay prices. However, the increased use of feedstuffs by fermentation industries results in by-product feeds that can be utilized best by beef cattle. Utilization of these by-product feedstuffs by cattle not only results in cheaper feed, and therefore production costs, but also enhances the sustainability of the fermentation industry. The objective of this research was to evaluate puberty onset and subsequent reproductive performance in heifers fed a traditional ration with grass hay to rations in which grass hay was substituted with either grass-seed straw or a grass seed straw-brewer's grain silage. Eighteen heifers (initial body weight = 561±11.4 lbs and age = 278±2.4 d) were randomly assigned to one of three treatment groups: grass hay (HAY), grass seed straw (STRAW), or grass seed straw-brewer's grain silage (SILAGE). Heifers were individually fed twice daily using Calan gates for 22 weeks. Heifers were weighed and 10-ml blood samples were recovered weekly. Plasma was recovered by centrifugation and stored at -20° C until analyzed for progesterone and Anti-Mullerian Hormone (AMH) concentrations. Puberty onset was defined as plasma progesterone exceeding 1 ng/ml. At week 21, heifers were estrous-synchronized using a CIDR-Select Synch protocol. Heifers displaying estrus were inseminated 12 h after onset with one straw of frozen semen. Heifers not displaying estrus were injected with PGF2[subscript alpha] 10 d after the initial PGF2[subscript alpha] injection in the CIDR-Select Synch protocol and subsequently observed for estrus and inseminated as described. Mean ages and weights of heifers were similar (P>0.10) across all treatments at the start of the feeding period. Heifer ages at puberty did not differ (P>0.10) due to treatment. Average daily gain of heifers during the feeding trial fed SILAGE were lower (P0.0005) than heifers fed either HAY or STRAW, However, no differences (p0.10) were found in body weight at puberty onset. However, body weights of heifers fed SILAGE were lower (P0.05) than heifers fed either HAY or STRAW at the starts of the breeding and calving seasons. No differences (P0.10) in services per conception, calving ease scores, calf vigor scores, or calf birth weights were observed between treatments. These results suggest that heifers fed the less expensive, by-product STRAW ration have weight gain and reproductive performance similar to heifers fed a traditional HAY ration. Although heifers fed the SILAGE diet had lighter body weights, a negative impact on reproductive measurements was not observed, suggesting the ration was adequate to support reproductive performance similar to a traditional HAY ration.

Download or read book Impacts of Stocking Density on Development and Puberty Attainment of Replacement Beef Heifers written by Kelsey M. Schubach and published by . This book was released on 2016 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: The following experiment presented herein compared growth, physical activity, stress-related responses, and puberty attainment in heifers reared on high- (HIDENS) or low-stocking densities (LOWDENS). Sixty Angus x Hereford heifers were ranked by age and BW (210 ± 2 d and 220 ± 2 kg, respectively) on d 0, and assigned to: a) 1 of 3 drylot pens (10 × 14 m pens; 10 heifers/pen) resulting in a stocking density of 14 m2/heifer (HIDENS; n = 3), or b) 1 of 3 pastures (25-ha pastures; 10 heifers/pasture), resulting in a stocking density of 25,000 m2/heifer (LOWDENS; n = 3). Pastures utilized herein were harvested for hay prior to the beginning of this experiment, and negligible forage was available for grazing to LOWDENS heifers throughout the experimental period (d 0 to 182). Heifers received the same limit-fed diet during the experiment, which averaged (DM basis) 4.0 kg/heifer daily of alfalfa-grass hay and 3.0 kg/heifer daily of a corn-based concentrate. Heifer shrunk BW was recorded after 16 h of feed and water withdrawal on d -3 and d 183 for ADG calculation. On d 0, heifers were fitted with a pedometer fixed behind their right shoulder. Each week during the experiment, pedometer results were recorded and blood samples were collected for puberty evaluation via plasma progesterone. Plasma samples collected on d 0, 28, 56, 84, 112, 140, 161, and 182 were also analyzed for concentrations of cortisol and IGF-I. On d 28, 102, and 175, blood samples were also collected for RNA isolation and analysis of heat shock protein (HSP) 70 and HSP72 mRNA expression. On d 0, 49, 98, 147, and 182, hair samples were collected from the tail switch for analysis of hair cortisol concentrations. No treatment effects were detected (P = 0.66) for heifer BW or ADG. Heifers from LOWDENS had more (P

Download or read book Effects of Winter Feeding Methods on Growth and Pregnancy of Developing Beef Replacement Heifers written by Chad L. Gasser and published by . This book was released on 2000 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Use of Dietary Fat Supplementation on Growth Reproduction and Performance Characteristics of Replacement Beef Heifers written by Alex Santos and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of these studies was to evaluate the effects of a dietary fat supplementation on growth, reproduction and performance characteristics of replacement beef heifers reared in different management systems (pasture and dry lot conditions). The objectives were (1) to quantify changes in body composition traits and growth performance of replacement beef heifers fed different levels of fat in the supplemented diet, (2) to determine the reproductive performance of heifers supplemented with dietary fat in either a ryegrass pasture system or a dry lot system, and (3) to determine the value of real-time ultrasound technology (RTU) as an alternative technology to assist producers in the decision making process within replacement beef heifer programs. Over the three year study, we observed that both high (3 - 5%) and low (1.5 - 2.5%)levels of dietary fat supplementation of replacement heifers did not have a negative affect in reproductive performance and body composition traits significantly, compared to controls (pasture-base, no supplementation. However, a positive response with respect to some body composition traits was observed in animals fed the higher level of dietary fat in 2004 and 2005 studies. Overall, growth of animals grazing ryegrass outperformed animals supplemented with dietary fat in a dry lot system; yet when dietary fat supplementation was integrated with a ryegrass pasture system, besides the positive effects in body composition traits metabolic changes in relevant reproduction hormones were observed with the addition of dietary fat treatment. Finally, the use of information on body composition traits of replacement beef heifers through the use of real-time ultrasound technology in the decision-making process resulted in a small financial return in these studies. However, the use of this alternative technology in a replacement beef heifer program may have additional value beyond the limited feeding periods reported here. These may include, a greater ability to predict heifer fertility as linked to growth and developmental characteristics (e.g., body composition traits), yet this requires further study.

Download or read book The Effects of Pre and Postweaning Nutrition on Fertility and Feed Efficiency in Beef Heifers written by Maggie K. Bloomsburg and published by . This book was released on 2018 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cattle in the Pacific Northwest graze a variety of forages which vary in quality. The effects of forage quality on heifer reproductive development and fertility is still under investigation. Therefore, the first objective was to investigate the effects of grazing different quality forages preweaning and postweaning on reproductive traits and feed efficiency in heifers. Although nutritional differences were present, pre- and postweaning treatments did not affect reproduction. This indicates different qualities of forage present in Idaho may be utilized for heifers. Feed costs represent a large portion of cattle producers' expenses. Selecting for feed efficiency allows producers to capitalize on these expenses. However, the effects of selecting for efficiency on reproduction is still undetermined. The second objective was to study the relationship between feed efficiency and reproductive development and fertility. No differences in reproductive traits were detected among heifers ranked as efficient, average or inefficient at utilizing feed for growth.

Download or read book Ovarian and Endocrine Dynamics Associated with Sexual Maturation in Beef Heifers and the Influence of Diet Weaning Age and Other Factors During Early Reproductive Development written by Chad Lamar Gasser and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: A series of experiments was designed to test the ability to induce precocious puberty in heifers and to determine the underlying mechanisms responsible for the precocious attainment of puberty. A model consisting of early weaning (3-4 months of age) and feeding a high-concentrate diet was used for each experiment. This method resulted in increased body weight gain. Additionally, precocious puberty was induced in a vast majority of heifers; and consequently, mean age at puberty was substantially reduced. Heifers that achieved precocious puberty did so at lesser body weights. In addition, subsequent estrous cycles continued after precocious attainment of puberty. In the first experiment, heifers that were weaned early and fed the high-concentrate diet exhibited a greater frequency of LH pulses leading to precocious attainment of puberty. In the second experiment, ovarian maturation was accelerated during the same period leading up to puberty. This was evidenced by increased maximum diameter of dominant ovarian follicles, increased duration of waves of ovarian follicular development, and increased peak estradiol concentrations during follicle waves. In the third experiment, estradiol-implanted, ovariectomized heifers that were weaned early and fed the high-concentrate diet escaped from estradiol negative feedback on LH secretion at a younger age, which was similar to the age at which ovary-intact heifers on the same diet attained puberty. It was concluded from these results that advancement of the decline in estradiol negative feedback on secretion of LH is the mechanism by which early weaning and feeding a high-concentrate diet induces precocious puberty in heifers. Essentially, the peripubertal period of development in heifers was shifted to a younger age with this model. A fourth experiment was conducted to determine the relative effects of timing of feeding the high-concentrate diet on age at puberty in early-weaned heifers. It was discovered that feeding the high-concentrate diet only for a period of 10 weeks after early weaning successfully advanced puberty to an extent similar to that of continuous feeding of the high-concentrate diet after early weaning. These experiments provide evidence that nutritional control during the early maturational period in heifers exerts substantial influence on timing of puberty.

Download or read book Hay Quality Breed and Ovarian Development Effects on Onset of Puberty and Reproductive Performance of Beef Heifers written by Randy Charles Perry and published by . This book was released on 1989 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bibliography of Agriculture written by and published by . This book was released on 1993 with total page 1732 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Effects of Diet and Weight on Induction of Puberty and Fertility Response in Yearling Beef Heifers written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Increased Nutruent Intake on Growth Reporduction and Productivity of Beef Heifers written by Shelby Lynn Rosasco and published by . This book was released on 2016 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two experiments were conducted to determine the influence of increased nutrient intake on beef heifer performance and reproductive efficiency. Experiment 1 evaluated the effect of heifer development supplementation regimen on heifer performance and reproduction during the pre- and post-breeding period. Heifers were developed grazing native range and supplemented to achieve 1) a constant rate of gain (CG) or 2) low rate of gain for the first half of development period followed by a high rate of gain for the remaining half of the development period (LoHi). Heifer performance was similar over the development period, with supplementation regimen having no effect on reproductive performance between treatments. Feed costs and costs to develop 1 pregnant heifer was decreased for LoHi heifer compared to CG heifers due to supplementation strategy. Following breeding heifers were stratified and randomly assigned to graze native pasture and supplemented at a low (CON) or high (High) rate for 30 d. CON heifer had a trend for increased AI pregnancy rate compared to High heifers, indicating a potential influence of nutrition on reproductive success. Accurately predicting forage nutrient composition during Exp. 1 impacted performance, altering predicted gains. In Exp. 2 heifers were individually fed a silage based diet to imitate treatments and predicted gains from Exp. 1. Heifer BW was similar among treatments over the development period. Although total ADG was similar among both treatment, ADG and intake was increased for CG heifers during the first 45 d, while LoHi heifer ADG and intake was increased over the last 45 d of the development period. Feed efficiency increased for LoHi heifers and decreased for CG heifers over the treatment period, indicating a potential compensatory gain effect. Reproductive traits measured were not impacted by development strategy; however, additional research is warranted to fully understand the impact of increased nutrient intake and compensatory gain on metabolic hormones, oocyte competence, and follicular microenvironment. In summary, these experiments provided further evidence of the impact of nutrition on reproductive performance, with future research warranted specifically investigating follicular fluid metabolic hormone concentrations and gene expression in oocytes and granulosa cells, and their impact on reproductive success.

Download or read book Changes in Whole Blood Parameters in Beef Heifers May Contribute to Delayed Pubertal Attainment written by Jessica A. Keane and published by . This book was released on 2021 with total page 107 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pubertal development in beef heifers is a transient period that has many contributing factors. Previously in our lab, progesterone (P4) concentrations collected from heifers at weaning (Oct) to breeding (May) were used to identify four distinct pubertal groups: Typical, Early, Start-Stop, and Non-Cycling. There is limited research on heifers and the impacts of whole blood cell populations, particularly WBCs, during pubertal development; however, girls with differing puberty onset displayed altered concentrations of hematocrit, white blood cells (WBC), and hemoglobin concentrations. Thus, our hypothesis was that heifer pubertal groups with delayed or precocious puberty may have increased white blood cells or altered whole blood parameters contributing to abnormal pubertal development. Weekly blood samples during the pre and peripubertal period were collected to obtain progesterone concentrations from previously identified pubertal classifications. Monthly blood samples were also analyzed with a HemaTrue ® Veterinary Hematology Analyzer to determine whole blood parameters. Additionally, blood smears were used to count specific WBC populations. All blood parameters were found to change during the collection period suggesting that weight and maturity directly impacts hematological and immunological factors. Early heifers tended to have reduced granulocyte cells (p=0.07) when compared to Typical (controls) but was not different from Start-Stop and Non-Cycling. Additionally, red cell distribution width to platelet ratio tended to be greater in Early compared to Typical ii and Non-Cycling heifers. Early and Start-Stop heifers that initiate puberty earlier had increased hematocrit (p=0.04) when compared to heifers with delayed puberty (NonCycling). Finally, Non-Cycling, heifers had reduced hemoglobin levels (p=0.03) compared to all other pubertal groups. Thus, hematological factors such as reduced granulocytes, increased hematocrit, and increased red blood cell width per platelet number may promote increased growth and development resulting in the probability that heifers will initiate puberty earlier. Furthermore, reductions in hemoglobin concentrations or functionality may delay pubertal attainment.

Download or read book The Effects of Norgestomet Or Norgestomet and GnRH on Attainment of Puberty in Beef Heifers written by Christine L. Henderson and published by . This book was released on 1994 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of Growing Beef Replacement Heifers on Wheat Pasture Before and During Breeding on Reproductive Peformance sic written by Marcha H. Bryant and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Photoperiod on the Development of Beef Replacement Heifers from Weaning Until First Lactation written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Photoperiod on the Development of Beef Replacement Heifers from Weaning Until First Lactation written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The effects of photoperiod on the development of beef replacement heifers from weaning until first lactation were determined by assigning 144 crossbred heifers on the basis of weaning weight (225 +- 23 kg) and sire breed (British/Continental) to two outdoor housing facilities, with different photoperiod treatments, in a completely randomized design. From December 1, 1998 (day 0) until May 20, 1999, heifers in one facility received supplemental light (423 lux, 1 m above ground) to extend the daily photoperiod (natural + supplemental light) to 16 hours (EP). Heifers in the other facility experienced natural photoperiod only (NP). Measurements of body weight gain, backfat, and concentration of prolactin in blood serum were made every 28 d. Observations for estrus behaviour were made twice daily, in the morning and evening, and were confirmed by serum progesterone concentration in blood samples taken 8-12 d after observed estrus. Two methods of estrous synchronization and timed artificial insemination (AI) were used for first service. Maternal performance as two-year olds was evaluated in terms of calving date (n = 105), milk production and composition during the period of peak lactation (n = 32), and calf weight. (Abstract shortened by UMI.).