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Lima F S - - 2009
The objective of this study was to compare reproductive performance of lactating dairy cows bred by natural service (NS) or timed AI (TAI). One thousand fifty-five cows were blocked by parity and enrolled to receive either NS or TAI. Cows in both groups were presynchronized with 2 injections of PGF(2alpha) ...
López-Gatius F - - 2010
Spontaneous reduction of advanced twin embryos has been described in high-producing, Holstein-Fresian (Bos taurus) dairy herds. The first objective of the current study was to determine whether management and cow factors could have an effect on such a reduction in twin pregnancies during the early fetal period. Because loss of ...
Takuma Tetsuya - - 2010
The aim of the present study was to determine whether the season (hot and cool) and reproductive phase (pregnant and non-pregnant) of the cow affect follicular recruitment and oocyte development. Follicular oocytes were aspirated from Japanese black cows by the ovum pick-up (OPU) method, which was performed 2 to 6 ...
Cadmus Simeon I B - - 2010
As a result of inadequate veterinary services and indiscriminate slaughter of animals in most Nigerian abattoirs, pregnant animals are often slaughtered resulting in wastage of scarce protein made available to the people. To this end, an evaluation of the volume of pregnant cows slaughtered at some abattoirs in Southwestern Nigeria ...
Yimer N - - 2010
The primary objectives of this study were to investigate incidence of abnormal ovarian cyclicity (AOC) and its type in dairy and beef cows with prolonged postpartum period (>90 days) and in heifers that fail to conceive. A total of 53 animals were included in the study: 17 Friesian crosses, 16 ...
Galvão K N - - 2009
The objectives were to determine the effects of PGF(2alpha) treatment on the prevalence of subclinical endometritis (SCE) and fertility of dairy cows. A total of 406 Holstein cows (167 primiparous and 239 multiparous) from 5 herds were used. Uterine lavage for diagnosis of SCE, PGF(2alpha) treatment, evaluation of body condition ...
Santolaria P - - 2009
This study was designed to assess the reproductive performance of Neospora caninum-infected dairy cows (Bos taurus) after abortion. The population examined was composed of 92 aborting cows subsequently subjected to at least one artificial insemination (AI) attempt. Of these animals, 68 were N. caninum seropositive and 24 were seronegative. Only ...
Lamb G C - - 2010
Early estrus-synchronization protocols focused on regressing the corpus luteum (CL) with an injection of PGF(2alpha) followed by detection of estrus or involved the use of exogenous progestins that prevent estrus from occurring. Later, protocols combining the use of PGF(2alpha) and exogenous progestins were developed. Gonadotropin-releasing hormone was utilized to control ...
Y??niz J L - - 2009
The aim of this study was to characterize the dynamics of the concentrations of heat shock protein 70 kDa (HSP70) in peripheral blood lymphocytes of lactating Holstein-Friesian dairy cows (Bos taurus) during pregnancy. The detection of pregnancy was carried out and blood samples collected on Days 40, 90, 120, 150, ...
Dobbins C A - - 2009
Our objective was to determine the optimal time to artificially inseminate lactating beef cows (Bos taurus typicus) after using the standard CO-Synch protocol that also included a progesterone-releasing, intravaginal controlled internal drug release (CIDR) insert. Cows (N=605) at three locations were inseminated at four different times after CIDR insert removal ...
Cooke R F - - 2009
The objective of this study was to evaluate, over 2 consecutive years, the effects of acclimation to human interaction on performance, temperament, plasma concentrations of hormones and metabolites, and pregnancy rates of Brahman-crossbred cows. A total of 160 Braford and 235 Brahman x British cows were assigned to the 2-yr ...
Leitman N R - - 2009
The objective of the experiment was to examine the necessity of adding a GnRH injection to a 14-d controlled internal drug release (CIDR)-based protocol for synchronization of estrus in beef heifers that were prepubertal or estrous-cycling at the initiation of treatment. The hypothesis tested was that the addition of GnRH ...
Santolaria Pilar - - 2010
The aim of this study was to determine possible relationships between farm climate conditions, recorded from day 0 to day 40 post-artificial insemination (AI), and late embryo/early fetal loss in high producing dairy cows. Pregnancy was diagnosed by rectal ultrasonography between 28 and 34 days post-AI. Fetal loss was registered ...
Friggens N C - - 2010
An improved understanding of the animal factors that affect measures such as conception rate would contribute to solving the problem of impaired reproductive performance in modern dairy cows. A question of particular interest relates to the observed improvement in conception rates from first to second and third oestrus cycle: is ...
Griffiths W M - - 2010
The ability to shift the supply of New Zealand chilled venison from farmed yearling red deer stags to obtain premium prices in seasonal European markets necessitates early calving of hinds combined with high growth rates of their calves. Two studies over a three-year period evaluated three management variables that offer ...
Lopes C N - - 2009
Five experiments evaluated the effects of rumen-protected PUFA supplementation on reproductive function of Bos indicus beef cows. In Exp. 1, 910 lactating primiparous Nelore cows were randomly assigned to receive 0.4 kg/d of a protein-mineral mix in addition to 0.1 kg/d of a rumen-inert PUFA source (PF) or 0.1 kg/d ...
Serrano B - - 2009
This study was designed to establish the factors, if any, which could affect plasma pregnancy-associated glycoprotein-1 (PAG-1) expression in a study population of 87 pregnant, high-producing dairy cows. The factors examined were: semen providing breed (Holstein-Friesian vs Limousin), outcome of gestation (male vs female newborn, and singleton vs twin pregnancies), ...
Green J C - - 2009
The ruminant trophoblast produces pregnancy-associated glycoproteins (PAG) that can be detected in the blood of pregnant animals. The objective was to determine the accuracy of a rapid ELISA PAG-based test for the purpose of pregnancy detection in cattle. Blood was sampled from dairy cattle (539 Holstein cows, 173 Holstein heifers, ...
Silva E - - 2009
The objective of this study was to compare 2 strategies for resynchronization of ovulation based on nonpregnant diagnoses using transrectal ultrasonography or a pregnancy-associated glycoprotein (PAG) ELISA. Lactating Holstein cows (n = 1,038) were submitted for first postpartum timed artificial insemination (TAI) using a Presynch + Ovsynch protocol. After the ...
Ohtsuka Hiromichi - - 2009
Older cows show a high incidence of infectious diseases during the periparturient period. The periparturient infectious diseases are closely associated with the immune function of dairy cows during the pre-calving period. In order to evaluate the relationship between the immune cell population and age in the cows during the pre-calving ...
Bartolome J A - - 2009
Pregnancy per artificial insemination (AI) was evaluated in dairy cows (Bos taurus) subjected to synchronization and resynchronization for timed AI (TAI). Cows (n=718) received prostaglandin F(2alpha) (PGF) on Days -38 and -24 (Days 39 and 53 postpartum), gonadotropin-releasing hormone (GnRH) on Day -10, PGF on Day -3, and GnRH and ...
Lauber M C - - 2009
Three experiments examined the impact of breed, time spent with dam (TWD), gender, and late pregnancy induction of parturition and caesarean on the behavioural and heart rate responses of dairy calves at 2 and 6 weeks of age to Open field, Novel object and Startle tests and a Learning task. ...
Nqeno N - - 2010
A study was conducted to determine the seasonal trends in ovarian activity, conception and pregnancy status of cows on communal rangelands in the Eastern Cape Province of South Africa. Ovarian activity and pregnancy status of 200 cows were determined through trans-rectal palpation in June, and October 2007 and January 2008. ...
Richards B D - - 2009
A total of 220 cows and heifers were treated with 3 mg/kg ketoprofen immediately after calving and 24 hours later, and 227 were left untreated as controls. The treated animals tended to have a lower incidence of retained fetal membranes and were 1.7 times less likely to develop the condition ...
Rodrigues C A - - 2010
The aim of the present study was to compare a synchronization of time of ovulation protocol for fixed-timed embryo transfer (FTET) with the usual administration of a single dose of prostaglandin associated with detection of estrus. Also, the effect of the presence of CL at the beginning of FTET protocol ...
Norman H D - - 2009
Reproductive information since 1995 from the USDA national dairy database was used to calculate yearly Holstein and Jersey means for days to first breeding after calving (DFB), 70-d nonreturn rate, conception rate (CR), number of breedings per lactation (NB), interval between first and last breedings during the lactation, days to ...
Alnimer M A - - 2009
Two modifications of the Ovsynch protocol, GnRH+TAI after PGF(2 alpha) 48 h (CO-48) or 72 h (CO-72), were compared with the original protocol (OVS: GnRH-7 d-PGF(2 alpha)-2 d-GnRH-16 h-TAI) to study their effects on reproductive performance in 785 lactating dairy cows (Holstein Friesian, Bos Taurus). Results showed that more cows ...
Peres R F G - - 2009
Two experiments were designed to evaluate strategies to increase fertility of Bos indicus postpubertal heifers and nonlactating cows submitted to a fixed-time artificial insemination (TAI) protocol consisting of an intravaginal device containing 1.9 g of progesterone (CIDR) insertion+estradiol benzoate on Day 0, CIDR withdrawal+estradiol cypionate on Day 9, and TAI ...
Kauffold J - - 2009
Previous studies have demonstrated the facilitating effect of a single cloprostenol treatment postinsemination on ovulation and pregnancy rate in dairy cattle and Italian buffalos. This study was conducted to test the effects of 500 microg cloprostenol given intramuscularly immediately postinsemination to 55 primiparous and 60 multiparous Holstein cows (Bos taurus; ...
Odhiambo J F - - 2009
Reduced capability of the uterus to support pregnancy in the absence of its interaction with secretions from male accessory glands has been demonstrated in rodents and to some extent in pigs. However, in cattle, the role of postmating inflammatory response on pregnancy success has not been studied. The current study ...
Bohmanova J - - 2009
Seven test-day models with different ways of accounting for the effect of pregnancy on production traits were compared by their residual variance, rank correlations of estimated breeding values of bulls and cows and number of nonpregnant cows in the top 500 for milk yield and milk persistency. Data were 22,546,696 ...
Brickell J S - - 2009
This study investigated the effect of growth parameters and metabolic indices during the rearing period on the fertility of nulliparous Holstein-Friesian heifers managed on 17 UK dairy farms. Growth parameters (body weight [BW], heart girth, height, and crown-rump length) and metabolic indices (insulin-like growth factor-I [IGF-I], insulin, glucose, and urea) ...
Dias C C - - 2009
Two experiments were performed to test the hypothesis that elevated progesterone concentrations impair pregnancy rate to timed artificial insemination (TAI) in postpuberal Nelore heifers. In Experiment 1, postpuberal Nelore heifers (n=398) received 2mg estradiol benzoate (EB) and either a new progesterone-releasing intravaginal device containing 1.9g of progesterone (CIDR) (first use) ...
Almer??a S - - 2009
Previous studies have shown that the use of beef bull semen significantly reduces the rate of abortions due to Neospora caninum in artificially inseminated (AI) seropositive dairy cows. In addition, certain beef breeds could be more resistant to N. caninum infection and abortion than others. The aim of the present ...
Loker S - - 2009
Preadjustment of phenotypic records is an alternative to accounting for the effect of pregnancy within the genetic evaluation model. Variance components used in the Canadian Test-Day Model may need to be re-estimated after preadjusting for pregnancy. The objective of this study was to assess the effect of preadjusting test-day yields ...
Colazo M G - - 2009
We compared the effects of porcine luteinizing hormone (pLH) versus gonadotropin-releasing hormone (GnRH) on ovulatory response and pregnancy rate after timed artificial insemination (TAI) in 605 lactating dairy cows. Cows (mean+/-SEM: 2.4+/-0.08 lactations, 109.0+/-2.5 d in milk, and 2.8+/-0.02 body condition score) at three locations were assigned to receive, in ...
Sá Filho O G - - 2009
In Experiments 1, 2, and 3, we evaluated the effects of temporary weaning (TW), equine chorionic gonadotropin (eCG), and follicle-stimulating hormone (FSH) treatments on results of a fixed-time artificial insemination (TAI) protocol in postpartum Bos indicus cows. In Experiment 1, treatment with 400 IU eCG or with TW for 48 ...
Mee J F - - 2009
The objectives of the study were to characterize an ultrasound reproductive tract scoring (URTS) system to assess suitability for breeding in dairy cows, to describe the prevalence of these scores in commercial dairy herds and to examine their relationship with subsequent fertility. Ultrasound examinations (7797) were performed on 5751 Holstein-Friesian ...
Galvão K N - - 2009
Objectives were to determine the effects of intrauterine (i.u.) infusion of ceftiofur hydrochloride on uterine health and fertility of dairy cows already receiving PGF(2alpha) for estrous synchronization. Holstein cows at 44 +/- 3 d in milk (DIM) were blocked by parity and diagnosis of metritis in the first 14 DIM ...
Rizzo Annalisa - - 2009
The follicular development in the cow occurs in a wave-like pattern, and it takes place also during pregnancy. In the cow, Equine Chorionic Gonadotropin (eCG) is used for superovulation, but a decrease in total fertility has been reported, likely because of its immunogenic properties in species other than equine. In ...
Sá Filho O G - - 2009
Five experiments were conducted on commercial farms in Brazil designed to develop the basis for an estrus synchronization protocol using melengestrol acetate (MGA) in Bos indicus cattle. These studies resulted in the development of the following protocol: 0.5 mg x d(-1) of MGA between d -14 and -1; 2.0 mg ...
Holm D E - - 2009
In this study, 272 beef heifers were studied from just before their first breeding season (October 15, 2003), through their second breeding season, and until just after they had weaned their first calves in March, 2005. This study was performed concurrently with another study testing the economic effects of an ...
Silva-Del-Río N - - 2009
Our objective was to determine the magnitude of, and factors affecting, pregnancy loss for lactating Holstein cows on a commercial dairy farm when diagnosed with twin (n=98) or single (n=518) pregnancies using transrectal ultrasonography. Pregnancy losses were assessed with records of non-viable embryos at first pregnancy examination and embryo losses ...
Gundling N - - 2009
Contents It was the aim of this field study to evaluate two different protocols of ovulation synchronization for the treatment of ovarian cysts and their effect on reproductive performance in dairy cows. In addition, factors with a possible influence on treatment success and pregnancy outcome as well as costs per ...
Ghanem M E - - 2010
The reason why cows carrying the mutation of complex vertebral malformation (CVM) show poor reproductive capability although they carry only one mutant allele is still not fully understood. Monitoring the progesterone profiles during oestrous cycle and early pregnancy in carrier cows might help explain their lowered reproductive capability. Progesterone concentration ...
Moghaddam A - - 2009
Thermal stress in cattle results in major decreases in dairy production and reproduction. A study was designed to evaluate the influence of temporary cooling on pregnancy rate in Holstein heifers during summer heat stress. Estrus was synchronized with two injections of prostaglandin [Formula: see text] (PG), administrated 11 d apart, ...
Long N M - - 2009
Fetal intrauterine growth restriction (IUGR) is known to negatively affect offspring health postnatally. This study evaluated the impacts of early gestational undernutrition followed by realimentation on bovine fetal and placental growth. Thirty multiparous beef cows bred to a single sire and gestating female fetuses were fed to meet NRC recommendations ...
Siochi R Alfredo C - - 2009
Full synchronization (FS) leaf sequencing removes tongue-and-groove underdosages (TGU) but increases the number of segments. Constrained partial synchronization (CPS) uses a minimum tongue-and-groove ratio (TGR) to reduce the number of segments while achieving acceptable TGUs. TGR is the ratio of non-overlapping intensities that irradiate a common junction. For TGRs of ...
Gautam Gokarna - - 2009
The objectives of this study were to ascertain the prevalence of different degrees of endometritis during different periods postpartum, to define 'clinically relevant endometritis', to determine its impact on subsequent reproductive performance, and to determine some risk factors for the incidence of clinically relevant endometritis in dairy cows. Holstein Friesian ...
Bucher A - - 2009
The objective of this study was to compare fixed-time AI pregnancy rate in Angus crossbred beef cows inseminated with frozen-thawed or fresh-extended semen. Two ejaculates from each of two Angus bulls were collected by artificial vagina and pooled for each bull. The pooled semen from each bull was divided into ...
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