Search Results
Results 101 - 150 of 1417
1 2 3 4 5 6 7 8 9 10 >
Assis Neto Ac - - 2010
The study is based on 141 pregnant Bos indicus cows, from days 20 to 70 post-insemination. First, special attention was given to the macroscopically observable phenomena of attachment of the conceptus to the uterus, i.e. the implantation, from about days 20 to 30 post-insemination up to day 70, and placentome ...
Garcia-Ispierto I - - 2010
The aim of this study was to investigate the effect of applying a progesterone-based oestrous synchronization protocol at 51-57 days postpartum in high-producing dairy cows. The data analysed were derived from 1345 lactating cows. Cows between 51 and 57 days postpartum were assigned to the groups: control, PRID (receiving a progesterone-releasing intravaginal ...
Plöntzke J - - 2011
The objective of this study was to evaluate the prevalence of clinical endometritis and its impact on reproductive performance in grazing dairy cattle in Argentina to compare data with previous reports from herds kept in confinement housing systems. A total of 243 Holstein dairy cows from three commercial dairy farms ...
Piechotta Marion - - 2011
The objective of the present study was to compare two commercially available blood-based pregnancy tests, namely BioPRYN, an ELISA for pregnancy-specific protein B (PSPB), and an ELISA for pregnancy-associated glycoprotein (PAG), for early pregnancy diagnosis in dairy cattle using transrectal ultrasonography as a gold standard. Transrectal ultrasonography was conducted 26-58 ...
Sá Filho M F - - 2010
The objective was to improve pregnancy per artificial insemination (P/AI; 35-42 d after AI) in virgin Jersey heifers bred by AI of sex-sorted semen after being detected in estrus. Giving 100 μg of GnRH at first detection of estrus, with AI 12 h later, did not affect P/AI in Experiment ...
Thompson I M - - 2010
Objectives were to develop a timed artificial insemination (TAI) resynchronization program to improve pregnancy per AI and to evaluate responses of circulating progesterone and pregnancy-associated glycoproteins in lactating cows. Cows (n=1,578) were presynchronized with 2 injections of PGF2alpha, given 14 d apart starting on d 45+/-3 postpartum, followed by Ovsynch ...
Dewey S T - - 2010
Objectives were to evaluate 3 resynchronization protocols for lactating dairy cows. At 32+/-3 d after pre-enrollment artificial insemination (AI; study d -7), 1 wk before pregnancy diagnosis, cows from 2 farms were enrolled and randomly assigned to 1 of 3 resynchronization protocols after balancing for parity, days in milk, and ...
Serrano B - - 2011
Pregnancy is characterized by transient changes in the maternal immune system, also evident at peripheral level. The present study analyzes the kinetics and possible factors affecting peripheral white blood cell populations throughout pregnancy in a herd of high-producing dairy cows chronically infected or not with Neospora caninum. We examined 54 ...
Wang Genlin - - 2011
The aim of the present study was to predict fetal sex at different time points of gestation in cattle by detecting the fetal SRY gene in cow plasma. Plasma DNA was extracted from the blood samples of 110 pregnant cows during the gestational period of 30 to 242 days. Nested ...
Karen Aly Mohamed - - 2011
The present study was undertaken to evaluate the accuracy of transrectal palpation (TRP) for diagnosing early pregnancy in buffaloes and the false diagnoses of the TRP test by using the pregnancy-associated glycoprotein radioimmunoassay (PAG-RIA) test. Pregnancy was diagnosed in 168 buffalo-cows once by TRP and PAG-RIA test between days 31 and ...
Hockey C D - - 2010
Many automated systems for detecting ovulating cows in dairy herds require decisions when designing algorithms and selecting cutpoints that require a compromise between diagnostic sensitivity (probability of classifying an ovulating cow as ovulating) and diagnostic specificity [daily probability of not classifying a non-ovulating cow (whether open or pregnant but not ...
Funston R N - - 2010
A 2 × 2 factorial arrangement of treatments was used to evaluate effects of dam winter grazing system and supplementation in the last third of gestation on subsequent BW gain, feed efficiency, and reproduction in heifer progeny. Crossbred cows (yr 1, n = 109; yr 2, n = 114; yr ...
Palomares R A - - 2010
The objective was to determine the effect of oxytocin treatments after calving on the incidence of RFM and reproductive performance in dual purpose cows under tropical conditions. Five hundred thirty six pluriparous, crossbred Zebu cows were randomly assigned to two groups: Oxy (n = 280): cows were given 30 IU ...
Pontes J H F - - 2010
Herein we describe a large-scale commercial program for in vitro production of embryos from dairy Bos taurus, Bos indicus, and indicus-taurus donors, using sexed sperm. From 5,407 OPU, we compared the number of recovered oocytes (n = 90,086), viable oocytes (n = 64,826), and embryos produced in vitro from Gir ...
Bisinotto R S - - 2010
Two experiments evaluated the influence of follicular wave at artificial insemination (AI) on fertility of dairy cows. In experiment 1, data from 5,607 lactating cows enrolled in estrous and ovulation synchronization programs for AI were evaluated. Cows' blood was analyzed for progesterone 7 to 14 d apart, with the second ...
Plöntzke J - - 2010
Recently several studies have reported that subclinical endometritis impairs reproductive performance in cattle. Most of the studies were conducted in western industrialized countries under intensive housing conditions. The objective of the present study was to determine the prevalence of subclinical endometritis and its impact on reproductive performance outcomes in clinically ...
Mallory D A - - 2010
Two experiments evaluated long-term progestin-based estrus-synchronization programs on the basis of potential for use in facilitating fixed-time AI in estrous cycling and prepubertal beef heifers. In Exp. 1, heifers were assigned to 1 of 2 treatments by age, BW, and estrous cyclicity status. Heifers assigned to the melengestrol acetate-PGF(2α) protocol ...
Brickell J S - - 2010
Associations between Neospora caninum infection and the reproductive performance of dairy heifers in their first and second pregnancy on 18 UK farms were examined. Six-month-old heifer calves were tested for N caninum-specific antibodies with a commercial ELISA, and were then monitored until their second calving. Random-effects regression analyses were performed ...
Shenavai Sima - - 2010
In late pregnant cows, progesterone (P(4)) is mainly of luteal origin. However, the trophoblast may provide high local P(4) concentrations in the uterus. To test for the importance of a complete P(4) withdrawal for parturition-related processes and placental release, the P(4) receptor (PGR) blocker aglepristone (Ap) was administered to three ...
Rafati Nima - - 2010
In last decade, pregnancy loss in dairy cattle has had an upward trend bringing difficulties for breeders: the annual cost is estimated around 396 billion Rials (i.e. around 40 million US$) for the Iranian dairy industry. The present study was conducted to determine the influence of maternal factors on abortion ...
Romano Juan E - - 2010
The objective was to evaluate the accuracy of an ELISA for pregnancy specific protein B (PSP-B) for early pregnancy diagnosis in dairy cattle. Blood from lactating (>100 d postpartum) dairy cows (n = 738), was collected on Days 28, 30, and 35 (Day 0 = estrus), analyzed with an ELISA ...
Whittier W D - - 2010
The objective was to compare the timed AI pregnancy rate of Angus-cross beef cows synchronized with a 5-d CO-Synch + CIDR (a progesterone-releasing intravaginal insert) protocol and given two doses of PGF(2 alpha) (PGF), with the first dose in conjunction with CIDR withdrawal on Day 5, and the second dose ...
Khoramian B - - 2011
Three different treatments were compared to improve pregnancy per artificial insemination (P/AI) in repeat-breeder (RB) dairy cows. All cows (n=103) were assigned to one of four groups: (1) gonadotropin-releasing hormone (GnRH); (2) human chorionic gonadotropin (hCG); (3) once-used controlled internal drug release (CIDR) device; and (4) control. All treatments performed ...
McArt J A A - - 2010
The objective was to compare the reproductive efficacy of Ultrasynch, a synchronization program based on functionality of the corpus luteum as determined by ultrasonography, with an Ovsynch protocol. A randomized field trial was conducted on a commercial dairy in Cayuga County, New York, during scheduled weekly pregnancy examinations. Cows (n=745) ...
Sigl Tanja - - 2010
ABSTRACT: After publication of this work we realised that some of the values were incorrect in Table 2. We have corrected these in the updated table.
Green J C - - 2010
The objective was to diagnose pregnancy within 18d after insemination by measuring interferon-tau (IFN-tau)-stimulated genes (ISG) expression in circulatory leukocytes. Based on microarray results, three genes were selected [2'-5' oligoadenylate synthetase 1(Oas1), myxovirus resistance gene 2 (Mx2), and interferon-stimulated gene 15kDa protein (Isg15)] because they were known to be interferon-stimulated ...
Kalantari A S - - 2010
The objective of this study was to determine the optimum replacement policy for Holstein dairy herds in Iran using a dynamic programming model. Cows were described in terms of state variables that included milk production class, parity, pregnancy status, and month in milk with a 1-mo stage length. The objective ...
Mellado Miguel - - 2010
Breeding records, including 649 inseminations during fall and winter at a dairy farm in a subtropical area of Western Mexico (24 masculine N; 24 degrees C, mean annual temperature 24 degrees C) were analyzed to document effects of sex-sorted semen from commercial Gyr bullls, estrus synchronization protocol, inseminator, sire and ...
Oropeza Armando José - - 2010
The objective of the study was to determine the efficiency of ovsynch (OV) versus presynch-ovsynch (P-OV) protocol for synchronization of ovulation and timed artificial insemination (TAI) in female buffaloes. The OV group (n = 40) received gonadotrophin-releasing hormone (GnRH) on day 0 (random day of the estrous cycle), prostaglandin PGF₂α ...
Villarroel Aurora - - 2010
The objective of this study was to evaluate the effect of parturition induction on dairy cattle with long gestation (past due-date) single pregnancies on calf survivability, cow health, production, and reproduction. There was an induction period during which all cows and heifers reaching 282 days of gestation were induced with ...
Sá Filho M F - - 2010
The objectives of the present study were to evaluate factors associated with estrous synchronization responses and pregnancy per insemination (P/AI) in Bos indicus beef cows submitted to progesterone-based fixed-time artificial insemination (FTAI) protocols. A total of 2388 cows (1869 Nellore and 519 crossbred NellorexAngus) from 10 commercial farms were evaluated ...
Yoshioka Hajime - - 2010
The objective of this study was to investigate the efficiency of estrus detection and determination of the time of ovulation in Japanese Black cows by a real-time radiotelemetric pedometer. A herd of Japanese Black cows was housed in a loose-housing barn. This pedometer system and a pressure-sensing radiotelemetric device, which ...
Yusuf Muhammad - - 2010
The objectives were to characterize repeat breeding in dairy cows, including reproductive performance and risk factors. Data from 613 Holstein Friesian cows in nine dairy herds across Japan were enrolled. A repeat breeder was defined as a cow that did not become pregnant after three inseminations, despite no clinically detectable ...
Rabaglino M B - - 2010
Two experiments were conducted to test the hypothesis that the 5 d Co-Synch + CIDR (Controlled Internal Drug Release insert containing progesterone) protocol could be applied as an efficient timed AI (TAI) protocol in dairy heifers, and that treatment with flunixin meglumine (FM) during the period of CL maintenance would ...
Chebel R C - - 2010
Our objective was to determine the effect of exogenous progesterone (P4) during a timed artificial insemination (TAI) protocol on pregnancies per AI (P/AI) in dairy cows not previously detected in estrus. Lactating cows (n=3,248) from 7 commercial dairy herds were submitted to a presynchronization protocol (2 injections of PGF(2alpha) 14 ...
Rabaglino M B - - 2010
The objective was to determine if the 5-d Co-Synch+CIDR (controlled internal drug releasing insert) protocol can be used in dairy heifers for a synchronized timed artificial insemination (TAI) with one injection of PGF(2alpha) for first and second services. In experiment 1, heifers were assigned randomly to receive 1 (n=295) or ...
Morton J M - - 2010
In year-round calving herds, reproductive performance has traditionally been described in relation to each cow's calving date. This research described reproductive performance in year-round and seasonal calving dairy herds using herd-level measures based on interval from each cow's initiation of breeding program date, and assessed interrelationships between such measures. A ...
Dahlen C R - - 2010
We determined the effects of administering hCG 7 d after a fixed-time AI (TAI) on ovarian response, concentrations of progesterone, and pregnancy rates in postpartum suckled beef cows. Cows at 6 locations received 100 microg of GnRH (Fertagyl, Intervet Animal Health, Millsboro, DE) and a controlled internal drug release (CIDR) ...
Warnick A C - - 2010
The objective was to determine physiological causes of low fertility in beef cows. Fertility was compared between low-fertility cows (34 British cows and 64 Brahman crossbred cows; cows that did not get pregnant when mated to fertile bulls in one or two previous breeding seasons); fertile cows (16 Brahman crossbreds; ...
Camargo Luiz Sergio Almeida - - 2010
In vitro embryo production (IVP) has been suggested to result in a greater proportion of male calves, longer gestation and heavier offspring than artificial insemination in Bos taurus cattle. Despite the increasing use of IVP in tropical countries, its effects upon these traits in Bos indicus have not been conclusively ...
Chagas L M - - 2010
AIM: To determine the effects of monopropylene glycol (MPG) on resumption of oestrous cycles and pregnancy rates in mixed-aged cows in commercial herds, when administered for 6 weeks before the planned start of mating (PSM). METHODS: A trial was conducted using 1,814 pasture-fed predominantly Holstein-Friesian cows on four spring-calving dairy ...
Wilson D J - - 2010
Two experiments evaluated short-term controlled internal drug release (CIDR) insert-based protocols to synchronize estrus and ovulation and compare differences in their potential to facilitate fixed-time AI (FTAI) in postpartum beef cows. Experiment 1 was designed to compare the 7- and 5-d Select Synch + CIDR protocols on the basis of ...
Stevenson J S - - 2010
Our objective was to determine whether rates of luteolysis or pregnancy differed in lactating dairy cows of known progesterone status and either known or unknown luteal status after either cloprostenol or dinoprost was injected as part of a timed-insemination program. In Experiment 1, 2358 lactating dairy cows in six herds ...
Ranasinghe R M S B K - - 2010
The objectives of the current study were to determine the incidence of silent ovulation (based on walking activity and milk progesterone profiles), identify risk factors for silent ovulation, and investigate its impact on reproductive performance in high-yielding dairy cows in free-stall housing. Overall, 277 lactations in 161 Holstein Friesian cows ...
S? Filho M F - - 2010
Two experiments were conducted to investigate the effects of equine chorionic gonadotropin (eCG) at progestin removal and gonadotropin-releasing hormone (GnRH) at timed artificial insemination (TAI) on ovarian follicular dynamics (Experiment 1) and pregnancy rates (Experiment 2) in suckled Nelore (Bos indicus) cows. Both experiments were 2x2 factorials (eCG or No ...
Zuluaga J F - - 2010
The objectives were to evaluate the effect of presynchronization with GnRH on pregnancy rates (Exp. 1) and ovarian events (Exp. 2) in Bos indicus-influenced females synchronized with CO-Synch + controlled internal drug release (CIDR) as described below. In Exp. 1, a total of 135 Brahman x Hereford (F(1)) females were ...
Gautam G - - 2010
The objectives of this study were to derive a useful case definition of delayed resumption of ovarian activity, based on factors associated with reduced fertility, and to assess its impact on subsequent reproductive performance in Holstein cows (Bos taurus). Milk samples were collected twice weekly from 219 cows from four ...
LeBlanc Stephen - - 2010
There is much debate about possible antagonism between high milk production and reproductive performance. This paper reviews methods of measuring reproductive performance and the association of the level of milk production with pregnancy rate at the herd and individual levels. The main question is whether fertility (the capacity for reproductive ...
Galon Nadav - - 2010
The objectives of this review are to describe the use of pedometry on commercial dairy farms in Israel, to evaluate its efficiency in heat detection and to describe a clinical trial comparing between pedometry and the Ovsynch technique. Pedometry is the major tool of heat detection on most farms in ...
Sah Shyam Kishore - - 2010
Anestrus is one of the most important reproductive disorders in dairy buffaloes. The clinical features of anestrus in buffaloes, however, have not been well described. The objectives of this study were to describe the causes of anestrus in buffaloes and their reproductive performance after treatment under field conditions in southern ...
1 2 3 4 5 6 7 8 9 10 >