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Glucocorticoids are commonly used to treat cows with clinical ketosis and fatty liver disease. This study investigated the effects of 10 mg/mL of FlucortRTM and PredefRTM 2X on the day of calving on blood metabolites, immune function and milk composition on 30 transitional Holstein cows. Sample of blood and milk were analyzed for energy metabolites (glucose, NEFA, BHB and insulin), mineral metabolites (Ca, P, Na, K, Cl and Mg), energy function parameters (antibody, lymphocyte), milk compositional parameters (protein, fat, lactose, SCC). There were no differences in glucose, Na, Cl, Mg, antibody, lymphocyte and milk fat, were observed among treatments. FlucortRTM treated cows had significantly lower NEFA on D1, higher BHB on D21 and D28, lower insulin on D14, higher Ca on D1 and lower P on D1. PredefRTM 2X treated cows had significantly higher BHB on D21, higher insulin on D7, lower Ca on D1, higher SCC on D1 and higher milk protein on D1. With respect to the significant data in this study, the use of glucocorticoids FlucortRTM and Predef RTM 2X in a single intramuscular injection on d1 for the treatment of ketosis is not warranted.

The objective of this study was to estimate the relationship between survival at various stages of productive life (17, 30, 43, 55 and 96 months of productive life) and type traits in Quebec Holstein and Ayrshire cows. The original data set from the Programme d'Analyse des Troupeaux Laitiers du Quebec contained 559,203 lifetime records calculated from 2,237,081 lactation records including calvings from 1979 to 1995. Lifetime records containing type classification information provided by the respective breed associations were used to study true survival variables (opportunity to survive to 17, 302 43, 55 and 96 months) and functional survival variables opportunity to survive to the same ages, independently of the level of production). K. Meyer's EQREML program was used to analyse these data by fitting a sire model. Heritabilities varied between 0.03 and 0.11 for both breeds. Final score and rear udder were two of the traits most highly correlated with survival. Specifically, in Holsteins, mammary system and fore udder showed the highest genetic correlation with functional survival, and dairy character showed the highest genetic correlation with true survival. In Ayrshires, final score, breed character, dairy quality, style and fore udder had the highest genetic correlations with both true and functional survival across all survival stages. In a second study, lifetime records not having type information and type records without lifetime information were analysed with D. L. Johnson and R. Thompson's AIREML program which enabled linking of sires in common between type and lifetime data sets. Only survival to 96 months was studied here, but the effect of supervised and non-supervised records was considered. In Holstein supervised records, body traits were more highly correlated with survival, whereas udder traits were more highly correlated in the non-supervised records. Ayrshire results were not conclusive.

A series of studies were conducted to evaluate genetic and phenotypic aspects of culling, herd life and survival in Quebec Holstein herds. Data consisted of lactation records obtained from the Programme d'Analyse des Troupeaux Laitiers du Quebec (PATLQ) files, which included 2.2 Million records before the editing procedures. The average productive herd life in Quebec herds was approximately 33 months, corresponding to an average replacement rate of MIND, for both milk recording options. Herds enrolled in the PATLQ official option had cows with longer calving intervals and culled their heifers earlier than herds in the owner sampler option. The probability of being culled for each major reason for disposal was assessed by logistic regression models, and it was shown that culling for low production (voluntary) had a clearly descending trend from 1981 to 1994, while involuntary culling (assumed to include all the reasons other than production) increased in importance mainly because of the ascending trends observed for cuffing due to reproductive problems, mastitis and feet and legs problems. Proportion of cows culled for involuntary reasons increased with parity number, but the opposite occurred for culling due to low production. Herds in the official option culled less for mastitis and sold more cows for dairy purposes than owner sampler herds. After these preliminary studies, a sequence of Weibull models were fitted to analyze different aspects of the data. The genetic study of herd life traits focused on differences between sires regarding true and functional herd life, but also described the effect of different explanatory variables on the failure time variable. Heritability for true and functional herd life was, respectively, 0.09 and 0.08 in the log scale and 0.19 and 0.15 in the original scale. The difference in the median survival time of daughters of bulls with extreme proofs for functional herd life was 1.7 lactations. Quebec dairymen use classification fo

Tiriamasis darbas buvo atliktas 2013 metais Lietuvos sveikatos mokslų universiteto Veterinarijos akademijos Gyvulininkystės katedroje. Bandymas buvo atliktas X ūkyje, esančiame Kėdainių rajone. Tyrimui naudota 20 holšteinų veislės karvių ir 20 simentalų x holšteinų F1 kartos mišrūnių. Visi gyvuliai antros laktacijos ir veršiavosi 2013 m. sausio – vasario mėn. Gyvuliai stebėti ir duomenys apie jų produktyvumą registruoti ir vertinti vienerius metus – nuo 2013 m. sausio 1 d. iki 2013 m. gruodžio 31 d. Darbo tikslas – atlikti pieninių simentalų mišrūnių ir holšteinų veislės karvių produkcijos rodiklių ir somatinių ląstelių skaičiaus piene palyginamąją analizę laktacijos eigoje. Uždaviniai: 1. Įvertinti ir palyginti pieninių simentalų mišrūnių ir holšteinų veislės karvių pieno sudėties rodiklius: primelžto pieno kiekį, baltymų, riebalų, laktozės ir urėjos kiekius piene. 2. Įvertinti ir palyginti somatinių ląstelių skaičių piene tarp pieninių simentalų mišrūnių ir holšteinų veislių karvių. 3. Palyginti abiejų veislių parduodamo pieno ekonominius rodiklius. 4. Palyginti pieninių simentalų mišrūnių ir holšteinų veislės karvių mėsos produktyvumo kokybinius ir kiekybinius rodiklius (parduodamų karvių gyvą svorį ir mėsos išeigą), taip pat atlikti abiejų veislių, ekonominį parduodamos mėsos vertinimą. Tyrimo metu nustatyta, kad vidutiniai primilžiai (simentalų mišrūnių – 8951,0 litrų, holšteinų – 8665,7 litrų) metų laikotarpyje buvo panašūs tarp abiejų veislių, tačiau pieninių... [toliau žr. visą tekstą] / Research was done in the Department of Animal Husbandry in the Veterinary Academy of the Lithuanian University of Health Sciences in the year 2013. Experiment was done in the X farm, located in Kedainiai region, Josvainiai district. 20 holstein cows and 20 simmental-holstein F1 generation hybrids were used for the research. All livestock was from the second lactation and were calving in November-December 2012. Livestock was observed and productivity data was registered and evaluated for one year: from 1st of January till 31st of December in 2013. Objective of the research – to perform comparable analysis of dairy simmental hybrids and holstein cows’ milk production composition and quality rate during lactation. Tasks: 1. To compare milk-producing simmental hybrids and holstein cows’ milk production productivity‘s quality and quantity rates: amount of milk yield, milk proteins, fats, lactose amount, number of somatic cells in the milk, amount of urea. 2. To compare milk-producing simmental hybrids and holstein cows’ meat productivity quality and quantity rates: meat weight and carcase mass. 3. To calculate financial rates of milk-producing simmental hybrids and holstein cows’ meat and milk. During the research it was stated that yield (simmental hybrids: 8951.0 l., holstein: 8665.7 l.) during the year was similar in both stocks (no essential differences have been found), but average annual amount of milk fat (0.32 percent unit) and protein (0,2 percent unit) in simmental... [to full text]

Univ., Diss./2000--Kiel, 1999.

Thesis (Ph. D.)--University of Missouri-Columbia, 2008. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 4, 2009) Vita. Includes bibliographical references.

Thesis (Ph. D.)--University of Chicago, 1942. / Lithoprinted. Includes bibliographical references (p. 84-87).

Thesis (Ph. D.)--University of Alberta, 2009. / Title from pdf file main screen (viewed on Aug. 14, 2009). "A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Animal Science, Department of Agricultural, Food and Nutritional Science, University of Alberta." Includes bibliographical references.

Berlin, Humboldt-University, Diss, 2003.