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The aim of the presented study was to estimate the influence of the traits of hoof measurement in dairy cows on claw disorders, lameness, and locomotion scores were determined. Data on claw health and measurement trait of claws were collected from 68 primiparous cows housed in tie stalls and from 76 primiparous cows housed in free stalls. Data were collected during professional claw trimming. The following claw disorders were recorded: sole haemorrhage, digital dermatitis, interdigital dermatitis, sole ulcer, interdigital growth, axial wall fissure, sand-crack (vertical fissure), laminitis, and dermatitis of the toe. Locomotion scores were defined directly before claw trimming. The angles of claws were measured in degrees with an electronic protractor. The heel depth, dorsal border, and diagonal sole surface were measured with an electronic caliper. Moderate association of claw measurements with claw disorders was demonstrated. No significant differences were found in hoof measurement traits between cows with normal gait and clinical lameness.
To construct a genomic library of Veillonella parvula H2, total DNA was extracted, sheared by a Hydroshear machine, and the DNA fragments ligated a into Smal-digested vector pUC18 before being transformed into E. coli DH5a. Colonies were selected on Luria-Bertani (LB) plates containing ampicillin, 5-bromo-4-chloro-3-indoyl-3-galactose (X-gal), and isopropy-β-D-thiogalactoside (IPTG) and proliferated. Recombinant plasmids were analysed for the presence of inserted DNA fragments of 3-4 kb by restriction mapping. The titre of the library was determined to be 10⁵ pfu/mL according to the formula N=ln(l-p)/(l-f). The genomic library consisted of 99% of the genome of Veillonella parvula, demonstrating a successful library construction.
The postpartal period in high-yielding dairy cows can be characterized as a time when animal has to undergo several important changes affecting all the organism. After pregnancy and parturition, organism has to adapt itself to the lactation and this stressing experience contributes to the high incidence of health disorders. These include ketosis, fatty liver, milk fever, retained placenta, metritis, mastitis, laminitis, and other metabolic and reproductive disorders. They may become clinically manifested in later stages of the reproduction cycle but have their primary cause in early postpartal period. To overcome these problems, every farmer has to practice good herd health management, especially when considering the transition period. To discover the weak points of the herd management we can use some indices that can be determined from the blood samples of dairy cows after partuition. We collected blood samples from 170 dairy cows of Slovak spotted breed 1 to 8 weeks after parturition. None of them manifested clinical signs of any illness. We divided them into the 6 groups depending on the number of weeks post partum.We observed and evaluated the main blood-chemistry parameters of energy and liver metabolism (glukose, triglycerides, total lipids, total cholesterol, non-esterified fatty acids, beta-hydroxybutyrate, total bilirubin), protein metabolism (total immunoglobulins, total protein, albumine, Creatinin, urea) and levels of some serum enzymes (AST, GGT, ALP, CPK, LDH). Even though there were no alterations in the health status present in that time, we found out that some indices, mostly of energy and liver metabolism, such as serum levels of non-esterified fatty acids, triglycerids, etc. were altered. This fact can help us to trace the potentially threatened individuals and to iniciate the steps that would minimize further damage.
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Based on data obtained using T4C herd management software from three farms equipped with milking robots, analysis was made of the effect of herd, age of cows, stage of lactation and milk production level on the number of visits to the milking robot and the proportion of different numbers of these visits. GLM and FREQ procedures of the SAS package were used for statistical analysis. The visits ended with 3.0 milkings and 2.6 refusals on average. The number of visits ending with milking decreased with advancing age and lactation, and increased with increasing milk production level. Among primiparous cows, 48% of the cows milked 3 times and 28% of the cows milked 4 times a day. Among multiparas, most cows milked 3 times (39%) and 2 times a day (37%). Most of late lactation cows (56%) milked twice, and in the other groups three times daily milking formed the largest proportion (around 45%). Considerable differences were found in the milking frequency depending on milk production level: among lowest yielding cows (≤ 20 kg milk) as much as 58% milked twice, and among highest yielding cows (≥ 50.1 kg milk) as much as 55% milked four times. The relatively high proportion of 5 refusals among the highest yielding cows (18%) and also among cows until 251 days of lactation (23-33%) should direct breeders’ attention to the proper balancing of diets for these cows.
The objectives of this study were to define the effect of the milk progesterone (P4) concentration on estrus expression in dairy cows with high milk yield and to identify the effect of milk yield and parity on the milk P4 concentration and cow’s pregnancy after artificial insemination (AI). In this study, 48 clinically healthy cows without reproduction disorders, on day 90-100 after calving were used. At the beginning of estrus and 12 hours after the beginning of estrus, the milk P4 concentration in dairy cows with high milk yield (group 3) was higher than in group 2 (33.66; 22.36%) and in group 1 (51.60; 65.26%) (P < 0.001). The milk P4 concentration in the ≥ 3 lactation cows was higher than the second (13.45%; P > 0.05) and the first (28.28%; P < 0.01) lactation ones (28.28%; P < 0.01). The milk P4 concentration at the beginning of estrus and 12 hours after the beginning of estrus in pregnant and non-pregnant cows was 2.58 and 3.32; 4.20 and 5.00 ng/ml, respectively (P < 0.001). As a result, it was concluded that high progesterone concentration affected the expression of estrus and pregnancy results in dairy cows, and the measuring of progesterone concentration in milk can be used as a non-invasive method to provide detailed information about fertility in high milk yield cows.
Body condition can influence bovine fertility, but the morphological, biochemical and endocrine mechanisms of this influence are not fully understood. The aim of the study was to examine the interrelationships between cow body condition, morphological and endocrine state of the ovary, and blood metabolic indexes. Czech Fleckvieh dairy cows at the follicular phase of the ovarian cycle and with a tendency towards emaciation (body condition scoreCS2) and cows with an average body condition score (BCS3) were compared. Plasma concentrations of aspartate aminotransferase (AST), non-esterified fatty acids (NEFAs), Ca2+, inorganic phosphorus (Pi ), Mg2+, Fe2+, Cu2+, Zn2+ (determined using photometrically), leptin and insulin (ELISA), ovarian area, number of visible ovarian follicles, diameter of primary and secondary ovarian follicles and corpora albicantia (macro- and micrometric analysis of ovarian histological sections), as well as the release of progesterone, testosterone, oestradiol and insulin-like growth factor I (IGF-I) by isolated ovarian granulosa cells (RIA) were analysed. No significant differences between BCS2 and BCS3 cows in blood metabolic and endocrine indexes (except for decreased Zn2+ in BCS3 cows) were found. The ovaries of BCS2 cows, however, showed a lower ovarian area, diameter of both primary and secondary follicles and corpora albicantia, but not the number of visible secondary follicles as compared with BCS3 cows. No differences between the release of progesterone, testosterone and IGF-I by ovarian granulosa cells isolated from BCS2 or BCS3 cows were found, but the granulosa cells of BCS2 animals released more oestradiol than those of BCS3 cows. These results indicate that a slight reduction in BCS (tendency towards emaciation) does not substantially affect ovarian secretory activity or metabolic blood indexes. On the other hand, a tendency towards emaciation is associated with reduced ovarian follicle growth (but not their number) and increased secretion of oestradiol. These observations suggest that a tendency towards emaciation can suppress bovine fertility via alterations in ovarian folliculogenesis and oestrogen release.
The effect of the transition of dairy cows from pregnancy to lactation on the expression of genes encoding enzymes involved in hepatic glucose metabolism was studied. Six Holstein-Friesian heifers were used for this study. Liver samples were collected by biopsy on day 7 before expected parturition (-7) and days 3 and 21 after parturition (+3 and +21, respectively). The mRNA levels of pyruvate carboxylase(PC),phosphoenolpyruvate carboxykinase 1 (PCK1), phosphoenolpyruvate carboxykinase 2 (PCK2), lactate dehydrogenase B (LDHB),fructose-1,6-bisphosphatase 1 (FBP1) and glucose-6-phosphatase (G6PC) were measured using quantitative real-time PCR. The expression of PC and PCK2 mRNA on day 3 of lactation was significantly higher than that on day 7 before parturition (P<0.05) and slightly higher than on day 21 postpartum. The LDHB gene showed the highest expression level on day 3 of lactation, as compared with day 7 prepartum (P<0.001) and day 21 postpartum (P<0.001). No differences were shown in PCK1, FBP1 and G6PC expression levels between pregnancy and early lactation.
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