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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Maize silage-based diets for finishing beef cattle

Browne, Elisabeth Mary January 2000 (has links)
No description available.
12

Effects of experimental fascioliasis on puberty and comparison of mounting activity by radiotelemetry in pubertal and gestating beef heifers

Paczkowski, Melissa Jeanne 01 November 2005 (has links)
Angus-sired heifers were allotted by age (mean=4 mo), BW (mean=135 kg), and sire (n=4) to either a control (n=10) or infected group (n=11; 600 metacercariae of Fasciola hepatica, intraruminally) to test our hypothesis that puberty is delayed by experimental fascioliasis. Blood samples were collected biweekly for analysis of steroid hormone concentrations. At 2-wk intervals, BW was recorded, and samples were collected for analysis of liver enzymes and serum proteins and fecal egg counts. A radiotelemetry system (HeatWatch??) was used to detect estrus and ovulation was confirmed by an elevation in serum progesterone (P4) after estrus. Heifers were artificially inseminated (AI) at the second observed estrus. Serum &#947;-glutamyl transpeptidase (GGT) and aspartate aminotransferase (AST) increased (p<0.0008) between day 0 and 112 in the infected group. Serum estradiol (E2) and P4 concentrations did not differ (p>0.1) between treatment groups. Mean age at puberty was 10 days later (p>0.1) in the infected group. Conception rate did not differ between control and infected heifers. The HeatWatch?? data were used to compare mounting activity during estrus in pubertal and gestating heifers. Mean duration of estrus was longer (p<0.01) for the second than for the pubertal estrus, though total mount duration and number of mounts did not differ. Number of mounts at second estrus was greater (p<0.05) for heifers that conceived (n=9). Mean duration of estrus and total mount duration at second estrus were not associated with pregnancy outcome. Estrus events were detected in all nine heifers during pregnancy (total=73). A majority (75%) of the interestrus intervals during gestation was <17 d. Number of mounts (p=0.035) and total duration of mounts (p=0.022) at second estrus were predictive of number of mounts during gestation. Experimental infection of Fasciola hepatica did not alter serum steroid hormone concentration or delay pubertal development in heifers. Estrus duration was longer for the second estrus compared to the pubertal estrus, and the number of mounts received during the second estrus was greater in heifers that did conceive to AI. Estrus events were detected in each heifer during pregnancy; however, a normal interestrus interval occurred in only 10% of the estrus events.
13

Effects of protein supplementation and source in cow/calf systems and heifer development

Martin, Jeremy L. January 1900 (has links)
Thesis (Ph.D.)--University of Nebraska-Lincoln, 2007. / Title from title screen (site viewed Dec. 5, 2007). PDF text: 132 p. : ill. ; 7 Mb. UMI publication number: AAT 3271935. Includes bibliographical references. Also available in microfilm and microfiche formats.
14

Gonadotropin Releasing Hormone its possible usage in the management of dairy heifers and postpartum cows /

Lee, Chin Nyean. January 1981 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1981. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 43-48).
15

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

Gasser, Chad Lamar, January 2005 (has links)
Thesis (Ph. D.)--Ohio State University, 2005. / Title from first page of PDF file. Document formatted into pages; contains xvii, 181 p. : ill. Includes bibliographical references (p. 159-181). Available online via OhioLINK's ETD Center
16

Effects of unilateral and bilateral pregnancy on maintenance of the corpus luteum and development of the conceptus in cattle

Del Campo, Marcelo Rafael. January 1980 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1980. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
17

Intake, Nutritive Value and Digestibility in Holstein Heifers Fed Diets Supplemented with Peanut Hay (Arachis Hypogeal L)

Phiri, Diniwe Grace 07 May 2016 (has links)
This study was conducted to measure the intake; nutritive value and digestibility of peanut hay (Arachis hypogaea L.). Fourteen Holstein heifers (BW= 408 plus/minus 32 kg; Age = 15.4 months plus/minus 0.5) were randomly allocated to two diets: peanut hay (PH) and corn silage (CS) adlibtum for 26 days. The PH consisted of 66:34 forage: concentrate (F:C) and CS diet contained 57:43 F:C ratio. Peanut hay at 91.8% DM contained 8% CP, 64% NDF, 51.9% ADF and 8 % ash. DMI and CP was not different across the treatment diets (P>0.05). NDF and ADF intake was different between the diets with PH being greater (P<0.01). Feed Efficiency using the feed to gain ratio was different across the diets (P<0.0001). Dry matter digestibility was 75.37% for CS diet and 68.53% for PH diet. Peanut hay basal diets formulated to contain low F:C ratio can increase growth in dairy heifers.
18

Performance Of Neonatal Holstein Heifers Fed Yeast Derivatives In Milk Replacer

Graves, Jessica Martin 10 December 2010 (has links)
Objectives of the present study were to evaluate neonatal Holstein heifer performance while supplemented with coccidiostat (CX), yeast (YST), β-glucan or some combination of these products in non-medicated milk replacer. Efficacy of these products on E. coli and coccidia shedding was also observed. No differences (P > 0.05) were observed among treatment groups with respect to performance data collected which included growth, feed intake and efficiency, fecal and respiratory and blood parameters. Heifers fed YST or YST + β-glucan had higher (P = 0.02 and P < 0.01, respectively) fecal E. coli concentrations compared to heifers fed CX, CX + YST, or β-glucan. No heifers showed clinical signs of coccidiosis and appeared to be healthy. These results suggest neonatal heifers may be supplemented with yeast derivatives without negative effects on growth or health performance.
19

The effect of management option on the performance of pregnant feedlot heifers

Simon, Michael Charles January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
20

Effect of GnRH, breeding weight, frame, condition and age on pregnancy rates in estrus synchronized beef heifers

Ferguson, Mary. January 1985 (has links)
Call number: LD2668 .T4 1985 F47 / Master of Science

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