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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.
221

Changes in abundance and distribution of humpback whales Megaptera novaeangliae in Hervey Bay Marine Park, Australia, based on aerial surveys conducted in 1992 and 2004

Suzacq, Lucía de la Paz 01 June 2007 (has links)
Aerial surveys were conducted throughout Hervey Bay Marine Park between August and October 1992 and 2004 to determine changes in abundance and distribution of the Eastern Australia humpback whale population in this area. Due to concerns about possible effects of boat traffic on whale distributions associated with a growing whale watching industry, the number and location of vessels were also recorded during these surveys. Throughout the 1992 season, 17 flights were conducted and a total of 41.93 surveys hours were completed, recording 186 pods, and a total of 320 animals. In addition, 392 boats were spotted in the area. During 2004, 10 flights took place with a total of 23.56 survey hours, 203 pods were sighted and a total 388 animals were recorded. In addition 216 boats were spotted in the study area.Results suggested an overall increase in the density of whale sightings from 1992 to 2004. By comparing total numbers for both years normalized to the number of survey hours, it can be seen that the total number of pods and the total number of individuals both increased. In 1992, with 7 more flights and an extra 10 hours on survey, the total number of pods and the total number of whales observed were less than in 2004. The composition of the pods showed a variation throughout both seasons consistent with a known distinctive temporal segregation of humpback whales on their annual migration. The percentage of calves was higher in 2004 than in 1992 consistent with the overall recovery of the eastern Australia population.Boat traffic did not show an effect on whale distributions in either year of the study. However this work provides a baseline for continuing to monitor boat traffic and whale distributions to help ensure that the east Australia whale population will continue to recover together with a sustainable growing whale watching industry.
222

QUANTIFICATION OF BOVINE SECRETORY IMMUNOGLOBULIN-A ANTIBODIES TO CLOSTRIDIUM PERFRINGENS B-TOXIN BY ENZYME IMMUNOASSAY: EFFECTS OF SYSTEMIC IMMUNIZATION OF DAM AND POST PARTUM CALVES ON SECRETORY IMMUNOGLOBULIN-A

Ireland, Timothy John January 1982 (has links)
No description available.
223

Untersuchungen zur Vermeidung des gegenseitigen Besaugens unter Kälbern durch den Einsatz eines Saugnuckels mit erhöhtem Saugwiderstand / Investigations for the avoidance of cross-sucking among calves by the use of an artificial teat with increased suckling resistance

Fischer, Amélie 24 January 2007 (has links)
No description available.
224

Laktobacilų padermių probiotikų savybių bei įtakos veršelių virškinimo trakto mikroflorai ir jų sveikatingumui tyrimai / The investigation of the probiotic properties of lactobacillus strains and their effect on the microflora in the digestive system of calves and their health condition

Oberauskas, Vaidas 14 March 2005 (has links)
1. Ištirtos registruotos Lactobacillus plantarum U-14, kuri išskirta iš sveikos karvės makšties ir Lactobacillus fermentum U-5, kuri išskirta iš sveiko veršelių fekalijų, padermės, nustatytos jų optimalios kultivavimo temperatūros, įvertintos jų probiotinės savybės, nustatytas antagonistinis aktyvumas, atsparumas antibiotikams bei įvertinta liofilizacijos įtaka šioms laktobacilų padermėms. 2. Liofilizacijos būdu pagamintas probiotikas, sudarytas iš Lactobacillus plantarum U-14 ir Lactobacillus fermentum U-5 padermių, nustatytas laktobacilų gyvybingumas preparate laikant vienus metus +4oC temperatūroje. 3. Nustatyta probiotiko profilaktinė dozė naujagimiams veršeliams girdant su krekenomis arba pienu pirmas 10 gyvenimo dienų, stebint veršelių klinikinius požymius, įvertinant paros priesvorį, įtaką bendram enterobakterijų ir laktobacilų kiekiui bei nustatant laktobacilų rūšinę sudėtį fekalijose įvertinant kraujo morfologinius ir biocheminius parametrus.4. Nustatyta probiotiko profilaktinė dozė veršeliams, kuri buvo – 4g/d. ir ji palyginta su probiotiko Yeasture profilaktine doze. / 1.The registered strains of Lactobacillus plantarum U-14 isolated from the vagina of healthy cow and Lactobacillus fermentum U-5 isolated from the faeces of healthy calve were studied, the optimal temperature for the cultivation was defined, were evaluated their probiotic properties, the antagonistic activity, resistance to antibiotics and the effect of lyophilization on these strains of lactobacillus were studied. 2.The probiotic preparation, consisting of Lactobacillus plantarum U-14 and Lactobacillus fermentum U-5 strains was produced by the method of lyophilization and the viability of lactobacillus during the period of 1 year storage at +4oC temperature was defined. 3.The preventive dose of probiotic preparation for neonate calves given with colostrum or milk was defined during the first 10 days, the clinical signs of calves, daily weight gain, effect on the total number of enterobacteria and lactobacillus were studied and the lactobacillus species composition in the faeces together evaluating morphological and biochemical indicators of blood was investigated. 4.The defined dose of probiotic preparation for calves was – 4g/d. and it was compared to the preventive dose of the preparation Yeasture.
225

Veršelių gyvybingumo įtakos pieno ūkio rezultatams tyrimas / Untersuchung Kälbersterblichkeitsrate und Überlebsrate auf die Wirtschaftlichkeit der Milchbetrieben

Ašmenskaitė, Lina 15 April 2005 (has links)
Ziel dieser Studie war es, den Einflüß von Totgeburten auf die Wirtschaftlichkeit der Milchbetriebe zu analysieren. Die Analyse basietr auf Daten „ Kaimo verslo plėtros ir informacijos centras“. Insgesamt lagen 26800 Abkalbendaten von 47 Bullen. Von den 10243 Milchkühen, deren Abkalbungen Ergebnisse geprüpft wurden, waren 8820 Schwarzbunte Milchkühe und 1243 Tiere gehören zu den Braunvieh. Einen Einfluss auf das Verlustgeschehen haben die Tatsache, ob es sich bei der Mutter um eine Erst-(5,9% mehr Verluste) oder Mehrfachgebärende handelt. Erstkalbinnen haben erfahrungsgemaß mehr Kalbeschwierigkeiten als Kühe. Zu fett gefütterte, überstürzt gewachsene Färsen haben eine Tendenz zu Totgeburten. Totgeburten sind wirtschaftlich von Bedeutung aufgrund der Kälberverluste und der Tierarztkosten sowie aufgrund der beeinträchtigung von Fruchtbarkeit, Leistung und Gesundheit der Muttertiere und den daraus entstehenden Folgenkosten.
226

Probiotikų reikšmė veršelių augimui ir virškinimo trakto mikroflorai / Importance of Probiotics to Growth and Microflora of the Digestive Tract of Calves

Kertenienė, Edita 20 April 2007 (has links)
The research has been accomplished in the Department of Anatomy and Physiology of the Lithuanian Veterinary Academy, in the Research Center of Digestive Physiology and Pathology and in the Center of Practical Training and Experiments of the Lithuanian Veterinary Academy in 2005 - 2007. The study consists of 50 pages. There are 3 tables, 13 pictures and 5 appendixes presented in it. In order to achieve high cattle productivity it is very important to establish optimal conditions for neonate calves breeding, to stimulate development of digestive tract and activate development of useful microflora, especially on the first month of calves breeding. The purpose of this work was to determine the influence of probiotic “Yeasture” to growth, wellness and microflora of the digestive tract of neonate calves, feeding probiotic to the calves on the first month of age. The experiment has been accomplished on Lithuanian-White neonate calves throughout the indoor period from November to January. Two groups of neonate calves were organized: control group (n=8) and experimental group (n=8). Calves of the experimental group were made to drink a preventive dose of the probiotic “Yeasture” every day, id est 5 g per day according to recommendations of the manufacturer. When the neonate calves were fed with the probiotic “Yeasture” supplement for the first month of age, their daily overweight had increased averagely by 16.1 percent. Probiotic “Yeasture” had no influence to daily overweight on the... [to full text]
227

Association between commensal bacterial establishment and mucosal innate immune genes expression throughout the gastro-intestinal tract of dairy calves

Malmuthuge, Nilusha Unknown Date
No description available.
228

Effects of a difficult calving on the subsequent health and welfare of the dairy cows and calves

Barrier, Alice Ce´cile Madeleine January 2012 (has links)
Yearly calvings are essential to the sustainability of modern dairy farming. Currently, calving difficulty (or dystocia) affects one in six calvings among UK dairy herds but vary from 2 to 50% internationally. In dairy cows, despite reports of impaired performance, the extent and threshold of the effect of dystocia on health and performance remains unclear. Over the past years, there has also been increasing concerns about the levels of pain experienced by the dystocial cows. Better understanding of their parturition progress and behaviours is needed so that informed decisions on pain mitigation can be taken. Additionally, the impact of dystocia (besides stillbirth) should also be addressed in dairy calves. The objective of this study was to address the effects of a difficult calving on the health and welfare of both dairy cows and calves. Retrospective analyses of an experimental farm’s detailed records were used to relate calving difficulty with health and performance of the dairy cow. The results showed that after any difficulty at calving, dairy producers incur long-lasting shortfalls in milk sales. Dystocial cows also have impaired fertility, are more likely to leave the herd early and have a higher risk of dystocia at the following calving, thus there is a long-term detrimental impact on dystocial cows. Video monitoring of calvings allowed detailed investigation of the parturition progress and behaviours of dystocial Holstein cows giving birth to singleton liveborn calves. The study of calving behaviours and parturition progress indicated longer later stages of parturition, increased restlessness and tail raising in the six hours preceding expulsion of the calf, for dystocial cows receiving farm assistance compared with cows calving unaided. This may relate to the expression of higher levels of pain when dystocia occurs. The onset of maternal behaviour was not delayed following calving difficulty, and firm conclusions could not be drawn from investigation of some behavioural indicators of pain in the first three hours postpartum. Experimental work allowed the monitoring of a cohort of 496 calves born with various degrees of birth difficulty over two years. All but one vet assisted calves were born dead, and farmer assisted calves were more likely to be stillborn than calves born without assistance. Stillborn dystocial calves displayed larger internal damage, than stillborn eutocial calves, but they did not have a different body shape at birth than dystocial calves that survived. Dystocial dairy calves that survived the birth process had lower vigour at birth, had higher salivary cortisol, acquired lower passive immunity and received more health treatments in the neonatal period. Dystocial heifers also had higher mortality rates by weaning but had similar growth to first service. Historical records from the farm also showed that dystocial heifer calves were three times more likely to have died by weaning and by first service than calves born without assistance. For those who survived, there was, however, no indication of altered growth to weaning or subsequent impaired fertility. This may be explained by the early mortality of the most badly affected calves or by farm management. However, their high mortality rates still raise welfare concerns. Altogether, results suggest that dairy calves born with any difficulty have poorer welfare in the neonatal period and possibly beyond. The experience of any calving difficulty in dairy cattle therefore not only impairs the welfare of the cow, but also the welfare from their resulting calf. Any strategy implemented to lower the occurrence and mitigate the effects of dystocia will therefore improve the welfare of the cows, their calves and enhance the farm’s economic sustainability.
229

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

Potter, Timothy January 2011 (has links)
No description available.
230

Acclimation of Holstein Calves to Transit Stress: The Integration of Endocrine, Immune, and Behavior Systems

Adams, Amber 2012 August 1900 (has links)
Little is known about the adaptation of livestock to repeated transport. This study determined how repeated transport affected calf feed intake, plasma cortisol (CORT), post-transport behavior, and the expression of immune-related genes. Thirty-six 4-month-old Holstein steer calves were housed in groups of six with each group randomly assigned to either transport (T) or control (C) treatments. The T calves were hauled for 6 h in a 7.3 m x 2.4 m goose-neck trailer, at an average density of 0.87 m2/calf, every 7 d for five consecutive weeks. Individual daily intake was determined using Calan gate feeders. Blood samples were obtained in the trailer or home pen via jugular venipuncture before loading, and after 2, 4, and 6 h of transport. Samples were analyzed for CORT, serotonin, tryptophan, and the gene expression of interleukin-4 (IL-4), interleukin-6 (IL-6), chemokine (C-X-C motif) receptor 2, interleukin-12, toll-like receptor-4, toll-like receptor-2, and 5-hydroxytryptamine receptor 2A in leukocytes. Behavior was recorded for transported calves at 5-min intervals for 1 h after return to their home pens. The C calves had a higher feed intake than T calves overall (P = 0.01), on the day of transport (P = 0.007), and the day after transport (P = 0.02). Pre-transport CORT concentrations did not differ by treatment (P = 0.77) or trial (P = 0.32). However, the T calves had higher response CORT concentrations than C calves during Transport 3 (P = 0.006), Transport 4 (P = 0.001) and Transport 5 (P = 0.02). The T calves had the highest response CORT concentrations after 2 h of transport and the lowest response CORT concentrations after 6 h of transport (P < 0.0001). Treatment did not affect gene expression in leukocytes, however, the expression of IL-4 (P = 0.01) and IL-6 (P = 0.05) was significantly lower after 2 h of transport than any other sampling times. These results suggest conflicting conclusions on whether the calves started to acclimate after being transported five times. However, CORT and gene expression differences occurred in response to the blood sampling regimen, which may provide insight to how calves acclimate during prolonged stress.

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