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Results 251 - 300 of 1408
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López-Gatius F - - 2008
This study was designed to examine estrous response rates to the therapeutic treatment of clinical anestrus in high producing dairy cows and to identify the factors that could affect these rates. Cows with silent ovulation (Subestrus group), cystic ovarian disease (Cyst group) or ovarian hypofunction (OH group) were given specific ...
Busch D C - - 2008
This experiment was designed to compare pregnancy rates in postpartum beef cows resulting from fixed-time AI (FTAI) at 54 or 66 h after administration of the CO-Synch + controlled internal drug-release (CIDR) protocol. Cows (n = 851) at 2 locations over 2 yr (yr 1, n = 218 and 206; ...
Abu Damir H - - 2008
Copper was determined in the blood of breeding camels, camel calves and racing camels to evaluate copper status in these animals in UAE. Low blood copper concentrations were reported in newly born camel calves (100%) and calves 2-4 months old (68%), breeding camels at early (55.6%) and at mid lactation ...
Holtz W - - 2008
This study assessed the efficacy of an Ovsynch protocol (vs. the classical cronolone containing vaginal sponge+eCG treatment) to generate fixed-time insemination in goats during the breeding season. Each regimen was applied to 24 Boer goat does. Onset and duration of estrus were determined with an aproned male and follicular development ...
Mee J F - - 2008
This review focuses on the case definition of dystocia, its current prevalence and recent temporal trends, the different types of dystocia and their associated risk factors in dairy cattle. The reported dystocia rates in dairy cattle internationally are generally <5%, apart from those in the United States, where they are ...
LeBlanc Stephen J - - 2008
This paper reviews the causes, impact, treatment, and prevention of retained placenta (RP), metritis, and endometritis in dairy cows. The occurrence of each of these diseases largely depends on immune function in the transition period. Retained placenta affects 5-10% of calvings and greatly increases the risk of metritis and endometritis. ...
Holzhauer M - - 2008
A cross-sectional study was performed, to (re)evaluate the prevalence of sole ulcers (SUs) and the risk factors involved in dairy herds that perform claw trimming on a routine base. Twenty hoof trimmers collected data on the presence or absence of claw disorders on the hind claws of dairy cows during ...
Brusveen D J - - 2008
Based on previous research, we hypothesized that Cosynch at 72 h [GnRH-7 d-PGF(2alpha)-72 h-GnRH + artificial insemination (AI)] would result in a greater number of pregnancies per AI (P/AI) than Cosynch at 48 h. Further, we hypothesized that P/AI would be improved to a greater extent when GnRH was administered ...
Iwakuma Akihiro - - 2008
Reproductive performance of two types of timed artificial insemination (TAI) protocols with or without intravaginal progesterone insert (CIDR) was investigated in a commercial herd of Holstein heifers. A total of seventy-four heifers with 14.4 months of age were allocated to two groups; Ovsynch (n=44) and estradiol benzoate (EB) used Heatsynch ...
Bridges G A - - 2008
Four experiments were conducted in postpartum beef cows to evaluate the influence of reducing the interval from GnRH to PGF(2alpha) from 7 to 5d in a Select-Synch + CIDR or CO-Synch + CIDR estrous synchronization program. In Expt 1, cows (n=156) were treated with either a 7 or 5d Select-Synch ...
Gábor G - - 2008
This trial was conducted on three Hungarian dairy farms between March 2003 and April 2004. The aims of this study were to examine the effect of milk production and milk contents, the day after calving (DAC) and the sire for the pregnancy rate (PR) and late embryonic loss (LEL) in ...
Barlund C S - - 2008
Holstein cows (n=221) from eight commercial dairy herds were examined for endometritis between 28 and 41 days postpartum using 5 diagnostic techniques: (1) vaginoscopy; (2) ultrasonographic assessment of uterine fluid volume; (3) ultrasonographic assessment of endometrial thickness; (4) endometrial cytology collected by cytobrush; and (5) endometrial cytology collected by uterine ...
Santos J E P - - 2009
The objectives of this study were to evaluate factors associated with resumption of postpartum estrous cycles and embryonic survival in lactating dairy cows. Holstein cows, 6396 from four dairy farms were evaluated to determine the relationships among parity, body condition score (BCS) at calving and at AI, season of year ...
Holzhauer M - - 2008
The effects of four different intervention strategies on the incidence of severe lesions of digital dermatitis in an experimental dairy herd were compared with the effects of a control strategy consisting of walking the cows twice through a footbath containing 4 per cent formaldehyde on one day a week for ...
Servet Bademkiran
The aim of this study was to investigate possible changes in the serum paraoxonase-1 (PON1) activity at the prepartum and postpartum stages in Holstein cows and to examine the relation between PON1 activity and dystocia. The 2nd objective of this study was to describe prepartum and postpartum serum concentrations of ...
Rhoads M L - - 2008
The somatotropic axis consisting of growth hormone, the growth hormone receptor (GHR) insulin-like growth factor (IGF)-I, and IGF binding proteins changes with the stage of lactation and nutrition of the cow and may be 1 mechanism through which lactation and nutrition affect the establishment of pregnancy. The objective of this ...
Poljak Zvonimir - - 2008
This research included 2 prevalence studies and a risk-factor investigation conducted in 2001 at 93 sites with sows only, finishers only, or both. In 2001, 1300 serum samples from sows in 65 herds and 720 serum samples from finisher pigs in 72 herds were tested for antibodies to swine influenzavirus ...
Balieiro J C C - - 2008
The objective of the present study was to estimate (co)variance components for length of productive life (LPL) and some alternative reproductive traits of 6-year-old Nellore cattle. The data set contained 57,410 records for age at first calving from Nellore females and was edited to remove animal records with uncertain paternity ...
Steinman Alan D - - 2008
A whole-lake alum treatment was applied to eutrophic Spring Lake during October and November 2005. Eight months later, an ecological assessment of the lake was performed and compared with data collected in 2003 and 2004. Field measurements showed reduced soluble reactive phosphorus (SRP) and total phosphorus (TP) concentrations in the ...
Cerri R L A - - 2009
Objectives were to evaluate progesterone concentrations after cows had initiated estrous cycles following calving and induction of estrous cycles in postpartum anovular high-producing Holstein dairy cows treated with controlled internal drug releasing (CIDR). In experiment 1 (EXP1), 62 cows that had initiated estrous cycles received a new CIDR (NCIDR) containing ...
Cirit Umüt - - 2008
In the present study, two new short estrus synchronization methods have been developed for lactating dairy cows. The study was completed in three consecutive phases. In experiment (Exp) 1, 32 cows, that were not detected in estrus since calving between the 50th and 84th post-partum days, were treated with PGF2alpha ...
Murray R D - - 2008
Perinatal mortality and stillbirths were investigated in an extensively managed herd of Friesian cows and heifers calving over a 2-year period: 504 cows were calved and 215 heifers. Cows were bred to Friesian and Jersey bulls using natural service. The perinatal fetal mortality rate was 7.5% for cows and 30% ...
De Rensis F - - 2008
This study was designed to compare the reproductive response to timed AI of lactating dairy cows with cystic ovarian follicles treated with GnRH or hCG to synchronize ovulation. The effectiveness of treatment during the warm or cool period of the year was also compared. Cows were given 12 microg GnRH-agonist ...
Silva E - - 2007
Our objective was to assess the effect of pretreatment with PGF(2alpha) 12 d before initiation of a protocol for resynchronization of ovulation (Resynch) using an Ovsynch protocol. Lactating Holstein cows diagnosed not pregnant 31 d after a timed artificial insemination (TAI) were randomly assigned to initiate the Resynch protocol 32 ...
Menchaca A - - 2007
Recent studies demonstrated that the Short-term Protocol of 5 days of progestogen treatment plus one dose of prostaglandin F(2alpha) and equine chorionic gonadotrophin (eCG) resulted in a close synchronized ovulation (60 h after the end of treatment approximately). In addition, oestradiol benzoate (ODB) is effective in synchronizing ovulation in goats ...
Gulay M S - - 2007
The objective of this study was to evaluate whether supplementing Holstein cows with bovine somatotropin (bST; 142.8 mg/14 d), beginning at 21 d (+/-3 d) before expected calving and continuing through 42 d in milk (+/-3 d), affected the incidence rates of retained fetal membranes (RFM), metritis (MET), clinical mastitis ...
González-Recio O - - 2007
Inbreeding depression on female fertility and calving ease in Spanish dairy cattle was studied by the traditional inbreeding coefficient (F) and an alternative measurement indicating the inbreeding rate (DeltaF) for each animal. Data included records from 49,497 and 62,134 cows for fertility and calving ease, respectively. Both inbreeding measurements were ...
Stevenson J S - - 2007
Our objectives were to determine relationships among factors influencing responses to the first GnRH injection in a timed artificial insemination (TAI) protocol and subsequent fertility after altering timing of the second GnRH injection and AI relative to PGF(2alpha) injection. Replacement heifers (n = 86) and 613 lactating cows previously inseminated ...
Freetly H C - - 2008
The purpose of this study was to determine if the efficiency of energy retention in pregnant cows was dependent on the time during the pregnancy that feed was offered. Our hypothesis was that restricting feed intake during the second trimester of gestation and providing the saved feed during the third ...
Bicalho Rodrigo C - - 2007
OBJECTIVE: To evaluate effect of twin birth calvings on milk production, reproductive performance, and survival of lactating cows. DESIGN: Retrospective observational cohort study. ANIMALS: 33,868 cows from 20 farms. PROCEDURES: Data on age at calving for primiparous cows and mature equivalent milk yield for multiparous cows, assistance at calving, stillbirths, ...
Martin J L - - 2008
Two experiments evaluated prebreeding target BW or progestin exposure for heifers developed lighter than traditional recommendations. Experiment 1 evaluated the effects of the system on heifer performance through subsequent calving and rebreeding over 3 yr. Heifers (229 kg) were assigned randomly to be developed to 55% of mature BW (299 ...
Shah Kapil Deo - - 2007
The aim of present experiment was to evaluate the plasma concentrations of estrone sulfate (E(1)S) and progesterone (P(4)) during late gestation in recipient cows transferred embryos produced by nuclear transfer (NT) and in vitro fertilization (IVF). Blood samples were collected from recipients transferred embryos produced by NT (n=9) and IVF ...
Zuluaga J F - - 2008
Objectives were to test the hypothesis that vaginal electrical resistance (VER) could be used to identify cows without a large (<10mm) follicle at timed-AI (TAI) following a synchronization of ovulation protocol and thus serve as a prospective decision aid for determining cows that should not be inseminated. Brahman x Hereford ...
Silva E - - 2007
To determine the accuracy of a pregnancy-associated glycoprotein (PAG) ELISA in identifying pregnancy status 27 d after timed artificial insemination (TAI), blood samples were collected from lactating Holstein cows (n = 1,079) 27 d after their first, second, and third postpartum TAI services. Pregnancy diagnosis by transrectal ultrasonography (TU) was ...
Bicalho R C - - 2007
Our hypotheses were that cows classified as lame during the first 70 d in milk have more days from calving to conception and a greater hazard of dying or being culled compared with cows that were not classified as lame. Our objective was to estimate the detrimental effects of lameness ...
Chou Yang Ling - - 2007
The detection threshold (DeltaR(50)) of resistive (R) loads is a function of the total background resistance (R(0)). Increased R(0) increases the DeltaR(50), but the ratio DeltaR(50)/R(0) remains constant. The respiratory-related evoked potential (RREP) is elicited only by R loads greater than the cognitive detection threshold, DeltaR(50). We hypothesized that the ...
López-Gatius F - - 2007
Many immunological aspects of pregnancy, such as the role played by gamma interferon (IFN-gamma) in abortion, are not well understood. Neospora caninum is an intracellular protozoan considered to be among the main causes of abortion in cattle worldwide. The present study analyzes the interaction between IFN-gamma production and N. caninum ...
Lee Je In - - 2007
This study investigated the effects of the herd, cow parity, the insemination protocol and season on the incidence of pregnancy loss (PL) in dairy herds. Furthermore, we determined the downstream effects of PL on reproductive performance and its economic impact. The overall incidence rate of PL was 6.9% in 1,001 ...
Galvão K N - - 2007
The objective was to determine if reducing the interval from presynchronization to the first GnRH injection (G1) of a timed artificial insemination (AI) protocol improves pregnancy per AI. One thousand two hundred fourteen Holstein cows, at 37 +/- 3 d in milk (DIM), were stratified by parity, DIM, and milk ...
Saber A P Reazai - - 2007
The aim of the present study was to compare the hepatic triacylglycerols (TAG) and total lipid and plasma Non-Esterified Fatty Acids (NEFA) and albumin in cows in different stages of productivity slaughtered at Ahvaz abattoir. So, a total of 203 blood and liver samples were collected from the indigenous hybrid ...
Kale M - - 2007
Some production parameters of seropositive cows (age, first calving age, 305 day mature equivalent last milk yield production, lifetime mature equivalent milk yield production, lifetime total milk production, lifetime total milking period, lifetime monthly milk production, lifetime daily milk production, lifetime total days of milking, number of inseminations per pregnancy ...
Galvão K N - - 2007
The objectives of this study were to evaluate the effect of 3 methods of resynchronization of estrus and ovulation for lactating dairy cows of unknown pregnancy status on conception rate and time to pregnancy. Holstein cows (n = 495) were randomly assigned to 1 of 3 treatments: 1) control (n ...
Lamb G C - - 2008
We determined whether insertion of a CIDR for 7 days prior to the breeding season enhanced pregnancy rates and altered the date of conception in suckled beef cows mated naturally. Suckled beef cows (n=2033) from 15 locations were randomly assigned to one of two treatments: (1) cows received a CIDR ...
Turk R - - 2008
Serum PON1 is a HDL-associated enzyme that protects lipoproteins, both LDL and HDL, against oxidation and it is considered as an antioxidative/anti-inflammatory component of HDL. Dairy cows are highly susceptible to oxidative stress which commonly occurs in late pregnancy and early lactation. During the transition period, increased production of reactive ...
Wittek T - - 2007
The changes in abdominal dimensions and contour during late gestation and early lactation were investigated in 44 Holstein-Friesian cattle, 20 normal heifers and 17 normal cows, and seven cows that had a left displaced abomasum (LDA) surgically corrected by a right flank omentopexy in a previous lactation. Abdominal measurements were ...
Starbuck-Clemmer M J - - 2007
The association between conception rate at first service and numbers of follicles developed during a follicular wave was examined in 102 suckled beef cows and 14 heifers. Follicular development was monitored using ultrasonography for either two (trial 1) or three (trial 2) consecutive oestrous cycles (pre-breeding, breeding and post-breeding equivalent). ...
Roche J R - - 2007
The objective of the present study was to identify and quantify relationships among dairy cow body condition score (BCS) and body weight (BW) and production variables in pasture-based, seasonal-calving herds. More than 2,500 lactation records from 897 spring-calving Holstein-Friesian and Jersey dairy cows were used in the analyses. Six variables ...
Ghasemzadeh-Nava H - - 2007
The aim of this study was to assess the effect of two periods of P4 therapy by CIDR on the 1st service Conception Rate (CR) of repeat breeder dairy cows. The cows were selected on the following basis: absence of dystocia, retained placenta and endometritis after the last parturition. They ...
Lay, Debbie
Plasma samples from dairy cows across two seasons (warm and cold) were re-assayed utilizing a more sensitive and uniform procedure in order to assess the use of progesterone and PGFM concentrations on the day of AI (Day 0) to day 8 in predicting future pregnancy status of the cow (pregnant ...
Banos G - - 2007
In this study, maternal effects were described as age of dam at first and second calving, first-lactation body condition score (BCS) of the dam during gestation, and milk yield of the dam. The impact of these effects on first-lactation daughter BCS, fertility, and test-day milk yield was assessed. The effect ...
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