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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.
91

Effect of rotation frequency and stocking rate on herbage quality and animal performance of cow-calf pairs raised on permanent pasture in Quebec

Bergeron, Michel, 1967- January 2000 (has links)
In Quebec, 62% of agricultural land is devoted to forage production and 20% of this is pasture. Pasture management provides the opportunity for farmers to maintain and improve the productivity of agricultural land, and to engage in sustainable ruminant production. An experiment was conducted on 42 hectares of pasture land to study the impact of management intensive grazing (MIG) on cow-calf productivity. The pasture area was divided into 18 paddocks and the experiment was conducted as a randomized complete block design with two blocks. The treatments were arranged as a 3 x 3 factorial of stocking rate and rotational frequency. The stocking rates (SR) were 0.5, 0.7, and 0.9 hectares per cow (HSR, MSR and LSR respectively); the rotation frequencies (RF) were two days, six days and continuous grazing (2d, 6d and C). Sixty-one purebred Angus cow-calf pairs were randomly assigned to each of the nine treatments, and the animals were grazed during two consecutive grazing seasons (1997 and 1998). Hay harvested early in the season was used for pasture supplementation late in the season. Increasing RF had no effect (P > 0.05) on forage mass available. Increasing SR from 0.9 to 0.5 cow-calf pairs ha -1 resulted in a linear reduction (P < 0.01) in individual cow gain, but increasing the SR caused a linear increase in cow gains ha-1. Calf gain ha-1 increased linearly (P < 0.01) in response to SR, but was unaffected (P > 0.05) by RF. A system of 6d rotation and high SR generated the greatest net revenue. The study showed little benefit of MIG on animal performance, but substantial benefits on efficiency of land use and economic performance.
92

ELK CALF SURVIVAL, MORTALITY, AND NEONATAL HABITAT USE IN EASTERN KENTUCKY

Seward, Nathan W. 01 January 2003 (has links)
I estimated survival, cause-specific mortality, and neonatal habitat use of elk (Cervus elaphus nelsoni) calves in eastern Kentucky. I also measured habitat characteristics of elk parturition sites and annual calf production . Radio-collared females were fitted with vaginal implant transmitters and monitored for parturition behavior to locate, capture, and radio-collar calves during the springs of 2001 and 2002. Thirty-seven adult females with implant transmitters were translocated from Logan, Utah, to Addington Wildlife Management Area (WMA) in eastern Kentucky. Additional females from previous releases during 1997 and 1998 were monitored for parturition behavior. Mean calf production for all females monitored (n=77) was 66.2%. Parturition sites (n=10) were typically in closed-canopy hardwood forest within 152 m of a forest/grassland interface. Female selected sites with more boulders, andlt; 20 slope, a higher percentage of woody saplings, and thicker vegetation between 1.0 2.25 m in height compared to random sites. Twenty-seven calves were radio-collared and intensively monitored by ground and aerial telemetry. Mean annual survival was 0.766 ( 0.103). Coyote (Canis latrans) predation, meningeal worm (Parelaphostongylus tenuis), and human-caused mortality may slow population growth. Retention of implant transmitters for 40 cows ranged from 1 to 276 days (61.6 3.0). Only 2 implant transmitters worked as designed and led to calf captures. I had better success (n=25) capturing calves by monitoring parturition behavior and searching areas where pregnant cows were suspected to have given birth.
93

CALF HEMODYNAMICS DURING VENOUS OCCLUSION AND HEAD-UP TILT

Kilfoil, Peter J 01 January 2007 (has links)
The potential role of lower limb blood pooling in reducing venous return to the heart during orthostasis and elevated venous pressure is investigated. This study compares lower limb capacitance, microvascular filtration, and peripheral resistance between a group of highly trained endurance athletes and a group of their sedentary peers. Seven endurance trained males were selected between the ages of 23-33 [(29.1 4.1 yr), mean SD]. The subjects weekly cycling mileage ranged from 80 to 150 miles per week with an average of 125 8.5 miles/week. Nine healthy, age-matched sedentary subjects (25.8 4.8 yr.) were selected for the control group, based upon their reporting they had not participated in repeated lower-body or cardiovascular exercise in the months prior to their study. Results show that both subject groups had similar calf venous capacitances, rates of capillary fluid filtration, and local flow shunting (vascular resistance change) in response to venous thigh occlusion and 70 head-up tilt (HUT). The only significant difference found between groups was the cyclist groups smaller rise in heart rate in response to HUT. The findings of this study suggest that cyclists are not predisposed to orthostatic intolerance due to any changes in lower limb function.
94

Pharmacokinetics and pharmacodynamics of antimicrobial drugs used in the treatment of calf pneumonia

Potter, Timothy January 2011 (has links)
No description available.
95

'The Bobby Calf' - non linear and non classical narrative structures in the cinema of unease

Scrivin, Nicholas January 2008 (has links)
This document outlines the research, development and production of a creative work and accompanying exegesis in partial fulfilment of the requirements for the Master of Communication Studies (MCS) programme. It includes the first draft of a feature film screenplay and an exegesis that explores the research conducted, the theoretical context of the work, and analyses the screenwriting process undertaken. The Bobby Calf (2008) is the first draft of a feature film screenplay that uses a non-classical and non-linear narrative structure to tell the story of its main characters and advance the plot. A psychological drama set in rural New Zealand, The Bobby Calf (2008) was originally inspired by the Janet Frame short story The Reservoir (1963), a story based on a group of youngsters who venture forth to discover the forbidden reservoir; a place their parents had forbid them from going. Set in the outskirts of a small farming settlement, the story is a dark and gothic depiction of rural life and the harshness of reality faced by those brought up in a lifestyle they did not choose. The story focuses on the journey of ADAM (21); both as a young boy in 1988 (called JOHNNY) and as a young adult in 1997, and his mother CATH; a woman whose dreams and aspirations for her son and indeed her own life are slowly slipping away. The story centres on Adam as he grows more uncomfortable with how his life has ended up, and his discovery that the life he has been destined to fulfil is not the one he has chosen. Accompanying the screenplay is an exegesis that explores the research conducted previously on the history of non-classical/non-linear narrative structures and the rationale behind the success and limitations of this now-popular form of storytelling. These types of narrative structures are not a new phenomenon, and as many authors have attested, the basis of this form of storytelling is rooted in the history of screenwriting and film making, and borrows many techniques from theatre and literature.
96

Characterization of polymerase and RNase H activities of Moloney murine leukemia virus reverse transcriptase in relation to models for retroviral plus-strand synthesis /

Kelleher, Colleen Diane. January 1999 (has links)
Thesis (Ph. D.)--University of Washington, 1999. / Vita. Includes bibliographical references (leaves 98-115).
97

Porovnání různých způsobů ustájení telat v období mléčné výživy / Comparison of different methods of milk-fed calves housing

DUBOVÁ, Dagmar January 2014 (has links)
Calf is the most important animal on the farm. Calf rearing should be given due attention as many problems and ailments in the herd as a whole have their origins in calves. The right choice of technology o f rearing can be crucial to the economy of the entire breed. Quality of calf housing is reflected in the overall level of rearing cattle in this category. It has a significant impact on the overall w ellbeing of animals, zoohygienic conditions and health situation.The aim of this thesis was to compare methods of rearing calves in individual outdoor sheds, where the calves were fed twice daily, with group housing in a spacious calving barn with multip le feeding through a feeding machine. We looked at weight gain, hea lth and welfare of the animals.The thesis was dealt with at a private farm of Václav Duba in Boubín near the town of Horažďovice. The experiment was conducted simultaneously in both systems of calf housing in the time period between May 1 2013 and October 14 2013. Both the observed groups of calves were fed the same amount of milk replacer, only with different frequency of intake. Both groups had the same number of 30 calves (15 heifers and 15 bulls) of Czech pied cattle. After completion of the milk feeding period the average weight of the calves in individual sheds was 107.2 kg and 110.8 kg in the calving barn. The calves which were fed by a feeding machine had an average daily weight gain of 0.787 kg; the calves in individual sheds had lower weight gain of 0.743 kg. The average consumption of milk replacer for calves in the individual sheds was 521.7 litres and for calves in the calving barn it was 516.8 litres. This indicator has been pro ven to have high statistical significance (P 0.001). The a verage daily temperature in the individual sheds was 19.7 °C; in t he calving barn it was 17.9 °C. A diarrheal disease was reported in four animals in the individual sheds, and in six animals in the calving barn. In calves reared in the individual shed mutual sucking of muzzle was found immediately after drinking. In calves fed using a feeding machine there was no sign of unsatisfied sucking reflex.
98

Posouzení úrovně výživy telat v daném zemědělském podniku

CHUDOBOVÁ, Monika January 2018 (has links)
The diploma thesis prepares the evaluation of the feed ration during the period of plant nutrition of calves in the monitored enterprise. The feed is evaluated on the selected farm on the basis of nutrient needs with respect to the recommended values - standards. Above the award, the feed for the heifers is evaluated. In the case of heifers, the feed dose, which is presented during the rearing of heifers, is compared with the average daily increments of one year (2017).
99

Vliv vybraných faktorů na úroveň pasivní imunizace telat / Effect of some factors on passive immunization level in calves

ŘEŽÁBKOVÁ, Zuzana January 2018 (has links)
The base for rearing healthy calves is a high level of passive immunity, which protects calves in a challenging period after birth. In examined herd of the Holstein cows was evaluated the influence of selected factors on the level of passive immunization in 57 calves, expressed as total protein content in calf blood serum. The selected factors were: the quality of colostrum, the time of first intake of colostrum after birth, the weight and sex of calves. The proper level of passive immunization was found only in 33 (57, 9%) calves in the studied breed. Insufficient immunization resulted in a high mortality which reached rate of 10% in 2017. The level of the passive immunization was most affected by the quality of colostrum (P < 0, 001) and the time of first drinking after birth (P < 0, 0230). The other observed factors (calf weight and gender) were not statistically significant. Adequate care for the youngest age category is crucial and influences the profitability of the breed.
100

Uso do acetato de melengestrol (MGA) associado a PGF 'NTIND.2' 'alfa' e a GNRH ou benzoato de estradiol em protocolos de inseminação artificial em tempo fixo (IATF) para vacas nelores paridas

Perez, Gabriela Campos [UNESP] January 2005 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2005Bitstream added on 2014-06-13T18:31:49Z : No. of bitstreams: 1 perez_gc_me_botfmvz.pdf: 244671 bytes, checksum: d92a00f6fbf47e3db20740d4e0a01437 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Os objetivos foram avaliar o efeito da remoção de bezerros (RB) no desenvolvimento folicular e na indução de ciclicidade e a eficácia do MGA precedendo protocolos de IATF, que utilizam GnRH ou BE, nas taxas de concepção a IATF e gestação. Foram utilizadas 163 vacas paridas em anestro da raça Nelore com 80 ± 29 dias pós-parto e ECC de 3,0 ± 0,29, divididas em 4 grupos: G1: (n=40, controle); G2: (n=42, RB): RB (60 h) 11 dias antes da estação de monta (EM); G3: (n=43, MGA + GnRH): MGA (MGA PREMIX®, 0,5 mg/dia, v.o.) por 10 dias, seguido por RB (60 h), após este período receberam GnRH (CYSTORELIN®, 50 mcg, i.m). Após 6,5 dias, PGF2α (LUTALYSE®, 25 mg, i.m.) que foi seguida por outra RB (54h). Após a RB, todos os animais receberam GnRH e foram inseminados; G4: (n=38, MGA + BE): MGA por 10 dias, seguido por RB (60h), após este período receberam BE (Estrogin , 1,0 mg, i.m.). Após 7 dias, PGF2α que foi seguida por outra RB (54h). Após 24 horas da PGF2α, os animais receberam BE e foram inseminados 30 horas depois. Após a IATF, nos 4 grupos, foi realizado observação de cio e IA (30 d) e por monta natural por mais 32 dias. A ciclicidade, o efeito do MGA e RB no desenvolvimento folicular, as taxas de sincronização, concepção e gestação foram determinados por exames ultra-sonográficos. A variável dias para ficar gestante foi analisada pela curva de sobrevivência, enquanto que as variáveis binomiais e contínuas foram analisadas por regressão logística e pelo GLM do SAS, respectivamente. Foram incluídos no modelo efeito de tratamento, ordem, sexo da cria e suas interações e ECC como co-variável. O MGA foi fornecido, ao G3 e G4, diariamente e os animais ingeriram, em média, 0,99 mg/dia de MGA. O MGA aumentou (P<0,05) o diâmetro do maior folículo (11,2 ± 0,28 vs. 10,3 ± 0,29 mm, respectivamente), que também foi maior (P<0,05) na associação MGA + RB... / The objectives of this trial were to evaluate the effects of calf removal (CR) on follicular development and its ability to induce cyclicity and the effects of melengestrol acetate (MGA) preceding TAI protocols, with GnRH or EB on conception and pregnancy rates. Suckled anestrous Nellore cows (n=163) with 80 ± 29 days postpartum and BCS of 3.0 ± 0.29 were assigned into one of four groups: G1: (n=40, control); G2: (n=42, CR): calf removal (60 h) 11 days before the breeding season (BS). G3: (n=43, MGA + GnRH): MGA (MGA PREMIX®, 0.5 mg/day, v.o.) per 10 days, followed by CR (60 h), and GnRH (CYSTORELIN®, 50 mcg, i.m) after CR. Cows received by PGF2α (LUTALYSE®, 25 mg, i.m.) 6.5 days later, and another CR (54h) followed by GnRH and TAI; G4: (n=38, MGA + EB): MGA per 10 days, followed by CR (60h) and injection of EB (Estrogin , 1.0 mg, i.m.) after CR. Cows received PGF2α 7 days later and 24 hours after that, all animals received another EB and were TAI 30 hours later. Calf removal was performed between PGF2α and EB (54 h). After TAI, in all groups, was performed heat detection and AI (30 d) and natural service per more 32 days. Cyclicity status, effect of MGA supplementation and CR on follicular development, synchronization, conception and pregnancy rates were determined by ultrasound. The variable days to pregnancy was analyzed by survival analyses and the binomial and continuous variables were analyzed by logistic regression and GLM of SAS, respectively. The effects of treatment, parity, calf gender and interactions were included in the model, BCS was included as covariable. The MGA was offered to G3 and 4 daily (mixed into the mineral) and the average consumption was 0.99 mg/day. MGA supplementation increased (P<0.05) follicular diameter (11.2 ± 0.28 vs. 10.3 ± 0.29 mm, respectively) Follicular diameter was also increased (P<0.05) when MGA was associated with CR (11.3 ± 0.26 mm)... (Complete abstract click electronic access below)

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