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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

Modelling bovine spongiform encephalopathy using a herd based stochastic approach

Tsutsui, Toshiyuki January 2000 (has links)
No description available.
2

Managing Personnel for Milking Parlors on Large Herds

VanBaale, Matthew, Smith, John 04 1900 (has links)
4 pp. / As today's dairy consolidates, cows are being milked more rapidly through larger milking parlors on larger dairies than ever before. Because milk is the primary commodity and source of income for producers, the harvesting of milk is the single most important job on any dairy. Producing high-quality milk to maximize yields and economic value requires effective parlor management, an enormous challenge for producers. Managing large parlors includes managing labor, milking equipment, as well as monitoring and evaluating parlor performance. The goal of parlor management for large herds is to enhance profits by maximizing milk yield, udder health, and overall efficiency. This may be accomplished by adequately training and motivating employees to efficiently milking clean, dry, stimulated teats using proper milking hygiene.
3

Productivity of Two Utah Deer Herds as Related to Nutrition

Pack, Clarence Leon 01 May 1976 (has links)
A study of mule deer occupying deer management units 53 and 54 in south central Utah was conducted from August, 1971 to May 1974 to determine food habits, caloric requirements, dietary nutritional levels, and productivity. Transects, fecal analyses, weight data, classification counts, and forage analyses were used to accomplish these objectives. Food habits of deer on the two units were similar, except for higher use of scrub oak on unit 53 and higher use of snowberry on unit 54. Deer on unit 54 were significantly larger than those on unit 53. Thus, their caloric requirements also were significantly higher. Deer productivity and the nutritional quality of deer diets on unit 54 were lower than on unit 53.
4

The potential of fenugreek (Trigonella foenum-graecum) as a forage for dairy herds in central Alberta

Montgomery, Janet Unknown Date
No description available.
5

The potential of fenugreek (Trigonella foenum-graecum) as a forage for dairy herds in central Alberta

Montgomery, Janet 11 1900 (has links)
Fenugreek (Trigonella foenum-graecum L.) is a single-cut, annual legume typically grown for seed. Fenugreek has potential as a forage because it maintains high quality throughout the growing season, and offers the benefits of a legume in a crop rotation. This work aimed to evaluate the growth of two fenugreek genotypes, AAFC F70 and CDC Quatro, in the central AB area over two growing seasons, and to evaluate fenugreek haylage degradation and digestion in dairy cows. In general, the two genotypes were similar in their growth patterns and fenugreek biomass yield was comparable to alfalfa in the same area. Plant quality was sufficient to be used for lactating dairy cows. The digestion studies revealed that while Quatro haylage was comparable to alfalfa haylage, F70 haylage was of lower quality and was not utilized to the same extent by dairy cows as the other two forage types. / Plant Science
6

Population Dynamics and Age Determination for Five Utah Deer Herds

Beall, David L. 01 May 1976 (has links)
Ages of 213 deer killed during the 1972 hunting season were determined by: (1) eruption-replacement and wear criteria in the field: (2) employing the tooth eruption-replacement and wear criteria under optimum laboratory conditions; and by {3) cementum-annulation counts . Incisors collected for cementum-annulation counts were decalcified in 5 percent nitric acid, sections 16-18 microns were cut on a cryostat and stained in hematoxylin for 18 ± 2 minutes . Age determinations by cementumannulation counts showed 87 percent agreement with the results obtained by eruption-replacement and wear criteria in the laboratory. Survival rates were estimated from the age distribution of 740 teeth aged by cementum-annulation counts . The average adult doe survival rate was 0.55 . Other population parameters were also determined. All five deer herds showed apparent negative rates of population change, averaging -0.14. The adult female survival rate appeared to be the major source of variation between units in rate of population change. The correlation between hunting pressure and the rate of population change was statistically significant .
7

Le troupeau et les moyens de sécurisation des campements pastoraux : une étude de la gestion des troupeaux de la Communauté Rurale de Tessekre, dans le Ferlo sénégalais / The herd and the security means of pastoral settlements. A study of management of the herds of Tessekre, Ferlo, Senegal : a study of management of the herds of Tessekre, Ferlo, Sénégal

Manoli, Claire 14 December 2012 (has links)
Dans les pays du Sud, l'élevage est soumis au défi de l'augmentation de la demande en produits animaux, qui devrait doubler à l'horizon 2050. Parallèlement, face aux changements globaux en cours (climat, démographie et pression sur les ressources, urbanisation), la question de la vulnérabilité des populations qui vivent de l'élevage se pose comme une question de plus en plus forte. Cette thèse se propose d'étudier les systèmes d'élevages pastoraux au regard de ces deux enjeux, de production et de sécurisation, et de répondre à la question suivante : quelles sont les relations entre les moyens de sécurisation mis en place par les campements pastoraux et la gestion technique et économique des troupeaux ? Cette question est traitée pour le cas de la communauté rurale de Tessekre, située dans la réserve sylvo-pastorale du Ferlo, au Sénégal, en zone sahélienne. Cette zone est quasi-exclusivement dédiée à l'élevage pastoral et fournit 25 % de la viande consommée à Dakar. Une approche pluri-disciplinaire a été mise en place, associant des travaux en zootechnie système sur le troupeau et des travaux en socio-économie sur la sécurisation des ménages. Le concept de sécurisation mobilisé dans ce travail se définit comme la capacité à durer sur le long terme en mobilisant différents moyens de sécurisation que sont: l'accumulation des troupeaux ; la diversification des activités et des revenus ; la mobilité à grande distance ; l'organisation de la famille. Dans une première partie du travail, des trajectoires sur le long terme des campements, de leurs activités et de leurs troupeaux ont été établies sur 16 campements. Ces trajectoires ont permis de voir comment étaient combinés les moyens de sécurisation dans les campements et d'établir des profils de sécurisation des campements. Couplées à une analyse statistique de la diversité des systèmes d'activités pour 508 campements de Tessekre, ces étapes ont permis de caractériser la diversité des contributions des troupeaux à la sécurisation. Dans une deuxième partie du travail, un suivi zootechnique de 10 campements a permis de caractériser la conduite technique et la gestion économique des troupeaux pendant une période d'un an. Cette étude a montré que, même une bonne année sur le plan climatique, et même pour des profils sécurisés, il n'y a pas forcément d'épargne réalisée grâce au troupeau. De plus, les troupeaux ovins sont apparus très exploités. Une épargne a pu être réalisée pour une partie seulement des troupeaux bovins ; et, même s'ils sont épargnés, les bovins contribuent à satisfaire les besoins monétaires des campements. De plus, des éléments de conduite technique (gardiennage, grande transhumance au Saloum, opérations des béliers Tabaski) ont été traités et reflètent les contraintes notamment d'organisation de la main d'œuvre familiale auxquels sont soumis les éleveurs. L'étude fine des opérations Tabaski en élevage ovin montre une diversité dans les façons de commercialiser et acheter les mâles alors que la conduite est plus homogène. Seuls les profils sécurisés ont pu mettre en place des opérations de grande ampleur. Dans une dernière partie, c'est un moyen de sécurisation particulier qui a été traité : celui de la mobilité des jeunes migrants à la recherche de diversification. Des entretiens ont été menés avec 12 personnes, dans les campements et en milieu urbain. Ces entretiens révèlent les différences de points de vue au sein du campement notamment en ce qui concerne la commercialisation des animaux : entre jeunes plus attirés par les modes de vie urbains, plus « gaspilleurs » ; et chefs de famille, garants de la sécurisation des campements et plus favorables à l'accumulation des troupeaux. Ce travail permet d'établir des ponts entre la sécurisation des campements, qui est un objet plus habituel des sciences humaines et le troupeau, objet des zootechniciens. / In tropical countries, the livestock sector has to answer to a great challenge: an increase in animal products demand from the markets, which is predicted to double until 2050. Simultaneously, global changes such as climate changes, demographic increase and pressure over natural resources highlight vulnerability issues of rural population depending on livestock activities. Therefore, livestock activities have to face to this double challenge. This thesis proposes to study pastoral livestock systems regarding this double challenge. In this thesis, our aim is to answer to the following question: what are the relations between security means used by pastoral settlements and the technical and economical management of the herds? This question is applied on the rural community of Tessekre, in the sylvopastoral reserve of Ferlo, Senegal. This Sahelian zone of Ferlo is nearly exclusively dedicated to pastoral livestock activities and provides 25 % of the meat consumption of Dakar. A pluri-disciplinary approach is here presented : we associated livestock farming systems approaches to study the herd, to socioeconomic approaches in order to study the security of pastoral settlements. Concept of security used in this thesis is defined as: the ability for pastoral settlements to last over the long term, using four different security means. These security means are: accumulation of the herds, diversification of activities and incomes, long distance mobility; familial organization.In a first step, long term trajectories of settlements, their herds and activities have been established for 16 settlements. It was therefore possible to describe how the means of security were used and combined in the settlements and to establish distinct security profiles. This approach was coupled with a statistical analysis of the diversity of systems of activities of the 508 settlements in Tessekre and resulted in the characterization of the diversity of possible contributions of the herds to settlements security. In a second step, a monitoring of the herds in 10 settlements was realized during one year. This study gave data about technical and economic management of the herds. We showed that, even during a year marked by good climatic conditions, and even for secured profiles, accumulation of the herds was not always possible. High off-take rates of sheep herds were always realized during the year of monitoring. Regarding bovine herds, accumulation was possible for a part of the herds; in all cases, even if they were accumulated, bovine contributed to monetary needs of the settlements. Technical management was studied through several elements: sheepherding, long distance transhumance to Saloum, Tabaski rams sales. This study highlights constraints in the organization of familial workers. The study on Tabaski sales showed a diversity in the ways herders sell and purchase rams, whereas herd technical management is more homogeneous. Only the secured profiles are able to realize Tabaski sales at a great scale. In a third step, a particular security means was studied: the mobility of young migrants looking for diversification. 12 interviews were realized both in the settlements and in Dakar. These interviews revealed the different point of views existing in the settlements, regarding animal sales: the ones of the young more attracted by urban and consumerists ways of life and the ones of the family chieves, more attached to the accumulation of the herds, a warranty for settlement's security.
8

Modelling the transmission of and effectiveness of control measures for Mycobacterium avium subsp. paratuberculosis in dairy herds

Marcé, Clara L. H. January 2010 (has links)
No description available.
9

Genetic aspects of calving, growth, and carcass traits in beef cattle /

Eriksson, Susanne, January 2003 (has links) (PDF)
Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 5 uppsatser.
10

Fear and aggression in large flocks of laying hens : effects of sex composition /

Odén, Kristina, January 2003 (has links) (PDF)
Diss. (sammanfattning) Skara : Sveriges lantbruksuniv., 2003. / Härtill 5 uppsatser.

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