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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.
1

Factors associated with health and fertility of dairy cows in Saudi Arabia

Alnaeem, Abdulmohsen January 2003 (has links)
No description available.
2

Reproductive and endocrine parameters of fat versus moderately conditioned mares following parturition

Cavinder, Clay Alan 02 June 2009 (has links)
An increase in time to ovulation following parturition could result in economic loss if the mare cannot successfully conceive within a short time after foaling. To evaluate if a difference exists in reproductive efficiency of fat- (body condition score of 7 to 8) versus moderately-conditioned (body condition score of 5 to 6), 24 mares were allotted to and maintained in their respective group from late gestation until pregnancy was confirmed following breeding on the second post-partum estrus. Days to ovulation, interovulatory intervals, conception rates, and endocrine profiles were analyzed. Serum concentrations of thyroxine (T4), insulin-like growth factor-1 (IGF-1) and leptin were assayed in order to characterize normal circulating blood concentrations. There were no differences (P>0.05) in mean interval from parturition to first ovulation (14.41 ± 1.07 and 16.18 ± 1.06 d), first to second postpartum ovulation (22.91 ± 1.07 and 24.33 ± 0.93 d), or in conception rates (91.67% and 83.33%) between the 2 groups. However, mares in moderate conditioning did lose a greater percentage of body fat upon foaling as compared to fleshier mares (0.82% versus 0.35%). Leptin concentrations were not different between the groups (P>0.05). Nevertheless, serum concentrations of T4 were higher (P<0.01) and IGF-1 concentrations lower (P<0.01) in moderate- as compared to fat-conditioned mares during times of ovulation and the interovulatory period. Results indicate that mares maintained in a fleshy body condition are not prone to reproductive dysfunction or lowered levels of fertility. The significance of the current results is important as it reassures the breeder that mares in a fatter body condition score (BCS of 7-8) should not demonstrate sub-fertility related to level of body fat. Additionally, results indicate that mares may need to be kept in a BCS of 6 in order to avoid losing enough weight upon parturition and early lactation to bring the BCS below 5. It suggests that varying amounts of circulating T4 and IGF-1 do not affect reproductive capabilities of mares in a BCS of greater than 5 following parturition.
3

Reproductive and endocrine parameters of fat versus moderately conditioned mares following parturition

Cavinder, Clay Alan 02 June 2009 (has links)
An increase in time to ovulation following parturition could result in economic loss if the mare cannot successfully conceive within a short time after foaling. To evaluate if a difference exists in reproductive efficiency of fat- (body condition score of 7 to 8) versus moderately-conditioned (body condition score of 5 to 6), 24 mares were allotted to and maintained in their respective group from late gestation until pregnancy was confirmed following breeding on the second post-partum estrus. Days to ovulation, interovulatory intervals, conception rates, and endocrine profiles were analyzed. Serum concentrations of thyroxine (T4), insulin-like growth factor-1 (IGF-1) and leptin were assayed in order to characterize normal circulating blood concentrations. There were no differences (P>0.05) in mean interval from parturition to first ovulation (14.41 ± 1.07 and 16.18 ± 1.06 d), first to second postpartum ovulation (22.91 ± 1.07 and 24.33 ± 0.93 d), or in conception rates (91.67% and 83.33%) between the 2 groups. However, mares in moderate conditioning did lose a greater percentage of body fat upon foaling as compared to fleshier mares (0.82% versus 0.35%). Leptin concentrations were not different between the groups (P>0.05). Nevertheless, serum concentrations of T4 were higher (P<0.01) and IGF-1 concentrations lower (P<0.01) in moderate- as compared to fat-conditioned mares during times of ovulation and the interovulatory period. Results indicate that mares maintained in a fleshy body condition are not prone to reproductive dysfunction or lowered levels of fertility. The significance of the current results is important as it reassures the breeder that mares in a fatter body condition score (BCS of 7-8) should not demonstrate sub-fertility related to level of body fat. Additionally, results indicate that mares may need to be kept in a BCS of 6 in order to avoid losing enough weight upon parturition and early lactation to bring the BCS below 5. It suggests that varying amounts of circulating T4 and IGF-1 do not affect reproductive capabilities of mares in a BCS of greater than 5 following parturition.
4

An easy to use system for determining range cattle body condition

Tolleson, Douglas R., Schafer, David W. 10 1900 (has links)
4 pp. / determining body condition for effective cattle management
5

Vliv kondice prasnic na jejich následnou reprodukční užitkovost / Impact of the condition saw on the reproduction parameters.

FRÜHAUF, Václav January 2010 (has links)
The aim of the diploma thesis was to analyse the saw body condition and to judge the impact of the condition on the reproduction parameters. The body condition effect on the live weight of piglets in the litter from the birth to the weaning was not proved. The sows classed into the fasting condition had longer farrowing interval than saws classed into the breeding condition. The level of decrease the live weight of the sows during the lactation did not dramatically influenced the number of piglets in the litter. The highest piglet looses from farrowing to weaning were found in the first three litters. For optimal breeding conditions is necessary to keep the sows in condition closest to the breeding (optimal) condition.
6

The Use of Serial Ultrasound Evaluation of Body Composition Traits to Predict Performance Endpoints in Commercial Beef Cattle

Clement, Sorrel A. 14 January 2010 (has links)
Bos indicus influenced primiparous heifers (n = 300) and yearling Beefmaster heifers (n = 172) were evaluated to determine relationships between serial carcass ultrasound traits and ability to breed in short (45 to 90 d) breeding seasons. Data collected included carcass ultrasound traits: ribeye area (REA), intramuscular fat (IMF), rump fat (UFAT), ribfat, weight, and body condition score taken at yearling age, pregnancy determination, before breeding, and after the breeding season when pregnancy status was recorded. A logistic regression analysis was used to determine the influence of ultrasound traits and body condition on pregnancy status. Odds ratios suggested the likelihood of primiparous cattle rebreeding would have been increased by 93% if IMF would have averaged 3.5% instead of 2.5% as yearlings, or an increase in the average ribfat as yearlings from 0.287 to 0.387 cm would have increased the odds of rebreeding by 88%. Increased average body condition score of 6.5 rather than 5.5 at 30 days postpartum in primiparous cows was estimated to have increased rebreeding 367%. The odds of yearling Beefmaster heifers successfully breeding during a 45-day season would have been increased by 73% (year 1) or 274% (year 2) by increasing REA 6.4 to 6.5 cm^2 at a year of age. Steers were serially scanned beginning at approximately 265 kg of body weight through harvest in 56 day +/- 6 intervals. Data collected included ultrasound measurements (ribeye area (REA), 12th rib fat thickness (RibFat), percent intramuscular fat (IMF), and rump fat (UFAT)), weight, and carcass data. Days to choice was calculated for each steer based on a linear regression. The IMF deposition was quantified as quadratic from scans 1-6 and linear when cattle were on full feed. Prediction models at scans 1, 2, 3, 4, 5, and 6 yielded R-square values of 0.20, 0.25, 0.41, 0.48, 0.59, and 0.49, respectively for days to choice. Odds ratios suggested that if steers in this study had averaged 3.78% at day 0 rather than 2.78, the odds of cattle grading premium choice or greater would have been increased by 300%.
7

Effect of nutrition on follicle development and ovulation rate in the ewe /

Viñoles Gil, Carolina, January 2003 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 4 uppsatser.
8

Genetic aspects of maternal ability in sows /

Grandinson, Katja, January 2003 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 3 uppsatser.
9

Monitoring Diet Quality and Projecting Body Condition Score in Cattle Using Fecal Near Infrared Spectroscopy and NUTBAL on a Southern Arizona Rangeland

Turner, Rachel Joy, Turner, Rachel Joy January 2017 (has links)
Range cattle grazing in semi-arid regions are commonly limited by lack of nutrients from low-quality forage. Due to this, ranchers are faced with the challenge of monitoring diet quality in order to address nutrient limitations. Near infrared spectroscopy (NIRS) of fecal samples is a method used to determine diet quality values like crude protein (CP) and digestible organic matter (DOM) in grazing animals. When combined with a nutritional balance analyzer such as the NUTBAL system, fecal NIRS can be used to monitor diet quality and project animal performance. Our research aimed to test the ability of NUTBAL to project animal performance as represented by body condition score (BCS) in cattle (n=82 Animal Units) grazing on the Santa Rita Experimental Range (SRER) in southern Arizona. Previous work conducted on other Arizona rangelands led to the hypothesis that fecal NIRS coupled with NUTBAL can be used to monitor diet quality and project BCS in a southern Arizona commercial grazing operation. Data collection occurred between June 2016 and June 2017. Standing biomass and botanical composition were measured before each grazing period, and relative utilization was measured following each grazing period. During the midpoint of grazing in each pasture, 30 body condition scores and a fecal composite of 15 samples were collected. Fecal derived diet quality varied between a maximum of 10.75% CP and 61.25% DOM in early August 2016, to a minimum value of 4.00 % CP and 58.40 % DOM in March 2017. This study confirmed the ability of fecal NIRS paired with NUTBAL to project future BCS within 0.5 a score point more than 80% of the time in cattle grazing on the SRER. With this information, cattle managers in southern Arizona can better address animal performance needs and nutrient deficiencies.
10

Effects of heavy metals on two small mammal species

Ressing, Sara Marlene 01 December 2012 (has links)
Research on the chronic effects of toxic chemicals on individuals, populations, communities, and ecosystems is imperative to regulate pollutants and preserve threatened species and habitats. I designed a two-pronged study to investigate the effects of heavy metal contaminants on small mammal populations, communities and body condition. To compare population and community metrics, I conducted a year-long mark-and-release study from over 5,400 trap nights on a contaminated and reference site within Crab Orchard National Wildlife Refuge, a Superfund site. During the second phase, I compared contaminant residues to body condition in 29 white-footed mice (Peromyscus leucopus) and 21 southern short-tailed shrews (Blarina carolinensis) from the Refuge and from three reference sites. Body weight, age structure, trapping success or species diversity did not differ between sites. Mice from the contaminated site were more abundant with lower reproduction (as number of juveniles per adult female). Cadmium in both livers and kidneys of mice and shrews was significantly greater on the contaminated site. Elevated renal cadmium in mice (96 ± 79 mg/kg dry weight) and shrews (242 ± 166 mg/kg dry weight) from the contaminated site could likely impair physiologic functions with long-term effects. For white-footed mice, increasing renal copper, lead, and nickel were good predictors of low ash, water, and protein but did not correlate significantly with crude lipid content. In shrews, however, metals either showed no relationship or, in the case of renal cadmium and copper were positively related to body condition as increased protein content. Simply comparing animals from reference versus contaminated sites provided few insights into overall community structure or population dynamics of white-footed mice. While metals explained as much as 40% of body condition (ash) in mice, findings in both species are counter-intuitive or refute predictions. Future studies should include manipulative field experiments that pair higher-resolution, biologic responses such as histologic and biomarker assays with population and community dynamics.

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