133 research outputs found
Pregnancy per artificial insemination and pregnancy loss in lactating dairy cows of a single herd following timed artificial insemination or insemination at detected estrus
No full textThangavelu, G., Gobikrushanth, M., Colazo, M. G. and Ambrose, D. J. 2015. Pregnancy per artificial insemination and pregnancy loss in lactating dairy cows of a single herd following timed artificial insemination or insemination at detected estrus. Can. J. Anim. Sci. 95: 383–388. The objective of this retrospective study was to determine the factors affecting pregnancy per artificial insemination (P/AI) and pregnancy loss in lactating dairy cattle. Breeding records (n=1466) for 5 consecutive years were evaluated from one dairy herd. The effects of type of breeding [timed artificial insemination (TAI; n=1246) vs. insemination at detected estrus (IDE; n=220)], parity (primiparous vs. multiparous), body condition score (BCS; low ≤2.5 vs. high >2.5), year, season (summer vs. other seasons) and fertility group (high fertile <3 vs. low fertile ≥3 inseminations), on P/AI and pregnancy loss (i.e., late embryonic/early fetal loss, abortion and stillbirth) were determined using the GLIMMIX procedures of SAS software. Pregnancy per AI was influenced by type of breeding and season. Pregnancy per AI was lower (P<0.05) in cows that were TAI (28.7%) than IDE (37.1%) and during summer (30.3%) than other seasons of the year (35.5%). Pregnancy loss was higher (P<0.05) in low BCS (9.1%) than in high BCS (1.9%) cows. However, parity, year, and fertility group affected neither P/AI nor pregnancy loss
Fecal and urinary lignans, intrafollicular estradiol, and endometrial receptors in lactating dairy cows fed diets supplemented with hydrogenated animal fat, flax or sunflower seed
No full textWe hypothesized that the inclusion of flaxseed in the diets of lactating dairy cows will increase urinary and fecal concentrations of the lignans, secoisolariciresinol diglycoside (SDG), enterolactone and enterodiol, reduce intrafollicular concentrations of IGF-I and estradiol, and subsequently reduce estradiol and oxytocin receptor expression in the endometrium. To test this hypothesis, 27 cycling, lactating Holstein cows were assigned to 1 of 3 diets supplemented with saturated fatty acids (SAT), flax (FLX), or sunflower (SUN) seed. Rations were formulated to provide 750 g supplemental fat/cow/d in all dietary groups. Ovulation (Day 0) was synchronized, and 5 d later, follicles > 8 mm were ablated by an ultrasound-guided procedure in all cows. Samples of blood (Days 0 to 14), follicular fluid (Day 5 and 15), endometrium (Day 15), as well as urine and feces were collected in a subset of the animals. The fecal concentrations of SDG and enterodiol were higher (P<0.05) in cows fed FLX than in those fed SAT or SUN. Enterodiol increased (P<0.05) in urine samples of cows fed FLX, compared to those of cows fed SUN. However, follicular estradiol concentrations on Day 5 and 15 and endometrial concentrations of estradiol and oxytocin receptors on Day 15 did not differ among the dietary groups. Mean plasma progesterone concentrations were higher (P<0.05) in cows fed FLX and SUN than in those fed SAT. In summary, a diet supplemented with flaxseed increased the concentrations of SDG and enterodiol in feces, as hypothesized, but did not alter intrafollicular concentrations of IGF-I or estradiol, or endometrial populations of oxytocin or estrogen receptors in lactating dairy cows
A WIDE-FIELD SURVEY FOR TRANSITING HOT JUPITERS AND ECLIPSING PRE-MAIN-SEQUENCE BINARIES IN YOUNG STELLAR ASSOCIATIONS
No full textThe past two decades have seen a significant advancement in the detection, classification, and understanding of exoplanets and binaries. This is due, in large part, to the increase in use of small-aperture telescopes (<20 cm) to survey large areas of the sky to milli-mag precision with rapid cadence. The vast majority of the planetary and binary systems studied to date consists of main-sequence or evolved objects, leading to a dearth of knowledge of properties at early times (<50 Myr). Only a dozen binaries and one candidate transiting Hot Jupiter are known among pre-main-sequence objects, yet these are the systems that can provide the best constraints on stellar formation and planetary migration models. The deficiency in the number of well characterized systems is driven by the inherent and aperiodic variability found in pre-main-sequence objects, which can mask and mimic eclipse signals. Hence, a dramatic increase in the number of young systems with high-quality observations is highly desirable to guide further theoretical developments. We have recently completed a photometric survey of three nearby (<150 pc) and young (<50 Myr) moving groups with a small-aperture telescope. While our survey reached the requisite photometric precision, the temporal coverage was insufficient to detect Hot Jupiters. Nevertheless, we discovered 346 pre-main-sequence binary candidates, including 74 high-priority objects for further study.Fil: Oelkers, Ryan J.. Vanderbilt University; Estados Unidos. Texas A&M University; Estados UnidosFil: Macri, Lucas M.. Texas A&M University; Estados UnidosFil: Marshall, Jennifer L.. Texas A&M University; Estados UnidosFil: Depoy, Darren L.. Texas A&M University; Estados UnidosFil: Garcia Lambas, Diego Rodolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Colazo, Carlos Roberto. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba; ArgentinaFil: Stringer, Katelyn. Texas A&M University; Estados Unidos. Middle Tennessee State University; Estados Unido
The determination of asteroid H and G phase function parameters using Gaia DR2
No full textThe Gaia mission will provide the scientific community with high-quality observations of asteroids of all categories. The second release of Gaia data (DR2) was published in 2018 and consists of 22 months of observations of 14 099 known Solar system objects, mainly asteroids. The purpose of this work is to obtain a catalogue of phase function parameters (H and G) for all the asteroids that were observed during the Gaia mission and that were published in DR2. For this purpose, we introduce an algorithm capable of building this catalogue from the magnitude and UTC epoch data present in the DR2 data base. Because Gaia will never observe asteroids with a phase angle of 0° (corresponding to opposition), but with phase angles higher than 10°, we added data from ground observations (corresponding to small phase angles) and thus improved the determination of the H and G parameters of the phase function. We also built a catalogue of the parameters of the H, G1 andG2 phase function. We compared our results of the H, G functions with those of the Astorb data base and observed that the level of agreement is satisfactory. © 2021 The Author(s).Funding from Spanish project AYA2017-89637-R is acknowledged. Financial support was received from the State Agency for Research of the Spanish MCIU through the Center of Excellence Severo Ochoa for the Instituto de Astrofisica de Andalucia (SEV-2017-0709). MC is a doctoral fellow of CONICET (Argentina). The resources to support astorb.dat were originally provided by NASA grant NAG5-4741 (PI E. Bowell) and the Lowell Observatory endowment, and more recently by NASA PDART grant NNX16AG52G (PI N. Moskovitz).Peer reviewe
DIGITAL SOIL TEXTURE MAPS OF ARGENTINA
No full textSoil fractions of Argentina in g/100g, Clay, Silt and Sand, for 4 standard depth intervals (0–15, 15-30, 30–60, 60–100) at 1000 m resolution. Including textural classes for the four standard layers and error estimation using random forest.
Global accuracy based on cross-validation
sp
RMSE
Rsquared
MAE
Sand 0-15 cm
16.189
0.640
11.069
Sand 15-30 cm
16.320
0.629
11.213
Sand 30-60 cm
16.676
0.618
11.364
Sand 60-100 cm
16.762
0.587
11.472
silt 0-15 cm
12.011
0.638
8.352
silt 15-30 cm
11.807
0.608
8.388
silt 30-60 cm
11.504
0.561
8.168
silt 60-100 cm
11.728
0.583
8.263
clay 0-15 cm
8.766
0.475
5.721
clay 15-30 cm
10.723
0.452
7.432
clay 30-60 cm
11.211
0.557
7.842
clay 60-100 cm
11.005
0.536
7.734Schulz G.A., Rodríguez D.M., Angelini M., Moretti L.M., Olmedo G.F., Tenti Vuegen L.M., Colazo, J.C., & Guevara M. (2022). Digital Soil Texture Maps Of Argentina And Their Relationship With Soil-Forming Factors And Processes. In Geopedology second edition (pp. XXXX). Springer, Cham
A prepartum diet supplemented with oilseeds high in oleic or linoleic acid reduced GnRH-induced LH release in dairy cows during second week postpartum
No full textBackground The objective was to determine the effect of prepartum diets supplemented with rolled canola seed (high in oleic acid) or sunflower seed (high in linoleic acid) on luteinizing hormone (LH) pulsatility and gonadotropin releasing hormone (GnRH)-induced LH release during early postpartum. Methods Thirty-one pregnant Holstein cows, blocked by body condition score, parity and expected calving date, were assigned to 1 of 3 prepartum diets supplemented with 8 % rolled canola or sunflower seed, or no oilseed (control) during the last 35 d of gestation. Blood samples were collected at Weeks (wk)-3, 0, +1 and +2, relative to calving, to determine non-esterified fatty acids (NEFA), Beta-hydroxy butyric acid (BHBA) and glucose. Additional blood samples were collected during wk1 (n = 5 per treatment) or wk2 (n = 5 or 6 per treatment), for 6 h, to measure LH pulsatility; thereafter, 100 mcg GnRH was administrated i.m., and blood was sampled for 4 h more, to measure GnRH-induced LH release. Results Dietary treatment did not affect prepartum energy balance, but cows fed the control diet were in a deeper state of negative energy balance during wk2, than those fed canola (P = 0.03) or sunflower (P = 0.01). Prepartum diets did not influence the mean plasma concentration of BHBA and glucose. However, NEFA concentration during wk2 was greater in control cows than those fed sunflower (P = 0.03) or canola (P = 0.07). Prepartum diets did not affect LH pulsatility (i.e. mean, minimum, maximum concentration, pulse frequency, and amplitude during wk1 and 2). GnRH-induced LH release did not differ among dietary treatments during wk1 but the mean GnRH-induced LH release during wk2 was either greater (P = 0.02) and tended to be greater (P = 0.09) in control cows than in those fed canola and sunflower, respectively. Conclusions Prepartum diets did not affect LH pulsatility and GnRH-induced LH release during the first week postpartum, but cows fed a diet supplemented with oilseeds high in oleic or linoleic acid released less LH than control cows, in response to an exogenous GnRH challenge during the second week postpartum
Comparison of 2 enzyme immunoassays and a radioimmunoassay for measurement of progesterone concentrations in bovine plasma, skim milk, and whole milk
No full textThe objective of this study was to compare 2 enzyme immunoassays (EIAs) with a radioimmunoassay (RIA) as to sensitivity and accuracy in the measurement of the progesterone (P4) concentration in bovine plasma, skim milk, and whole milk. The 72 samples from 24 lactating dairy cows expected to have either a high P4 concentration (cows in diestrus or pregnant) or a low P4 concentration (cows in estrus or anestrus) were analyzed by RIA, solid-phase EIA (SPEIA), which included a solvent extraction step, or direct EIA (DEIA) without solvent extraction. The overall mean concentrations of P4 did not differ (P < 0.4) among the assays. However, for the cows that were in diestrus or pregnant, the mean P4 concentrations (and standard error) were higher (P < 0.03), regardless of sample type, with RIA than with SPEIA, at 7.3 (0.7) and 6.1 (0.6) ng/mL, respectively. When only the high-P4 samples analyzed by RIA were compared, the mean P4 concentration was higher (P < 0.001) in whole milk than in skim milk, at 9.8 (1.0) and 4.1 (0.7) ng/mL, respectively. Although the mean P4 concentrations in the low-P4 samples did not differ (P < 0.80) among assays, the proportions of cows with a P4 concentration ≥ 1 ng/mL were 3%, 14%, and 44% for RIA, SPEIA, and DEIA, respectively (P < 0.01; DEIA > SPEIA > RIA)
The factors associated with postpartum body condition score change and its relationship with serum analytes, milk production and reproductive performance in dairy cows
No full textObjectives were to (1) identify factors associated with postpartum body condition (BCS) maintenance/gain, (2) determine the optimum pre-calving BCS predictive of postpartum BCS maintenance/gain, and (3) evaluate the relationship between postpartum BCS change categories, serum analytes and performance in dairy cows. The BCS were determined in 271 primiparous and 640 multiparous cows from 11 dairy herds in Alberta, Canada at (mean ± SD) 9.0 ± 2.3 d pre-calving and at 34.6 ± 4.0 d post-calving, using a 5-point scale with 0.25 increments. Cows were grouped into BCS change categories according to BCS change between post- and pre-calving as follows: lost ≥ 0.75 units (extreme loss; EL; n = 343), lost either 0.25 or 0.50 units (moderate loss; ML; n = 390), no change in BCS (maintained; M; n = 104), or gained ≥ 0.25 units (gained; G; n = 74). In a subset of 178 cows, the concentrations of glucose, beta-hydroxybutyrate, non-esterified fatty acids, urea, cholesterol, haptoglobin and aspartate aminotransferase were measured in serum at 9.0 ± 2.3 d pre-calving and at 8.2 ± 3.7 d post-calving.
The proportion of cows grouped into EL, ML, M and G categories were 38, 43, 11 and 8%, respectively. Pre-calving BCS, season of calving and sickness were identified as factors associated with BCS maintenance/gain. The optimum pre-calving BCS predictive of postpartum BCS maintenance/gain was 3.25 for primiparous cows and 3.00 for multiparous cows. Mean serum concentration of beta-hydroxybutyrate, urea, cholesterol and haptoglobin did not differ among BCS change categories. However, G cows tended to have greater mean serum concentration of glucose compared with ML cows, and mean serum concentration of aspartate aminotransferase tended to be greater for EL cows compared with other BCS change categories. Mean serum concentration of non-esterified fatty acids was greater post-calving for EL cows compared with other BCS change categories. Milk yield by 25 and 90 days in milk (DIM) did not differ among BCS change categories; however, peak and 305-d mature equivalent milk yields were greater for EL compared with G cows. Overall, EL cows had reduced fertility compared with other BCS change categories, including a smaller proportion of cows with a corpus luteum by 35 DIM, reduced pregnancy to first AI and pregnancy by 150 DIM, and reduced hazard ratio of pregnancy risk up to 250 DIM. In summary, EL cows had reduced fertility compared with other BCS change categories and increased milk yield compared with G cows. Ensuring cows calve at an appropriate BCS to promote BCS maintenance, or only moderate loss, will improve fertility without sacrificing milk yield
B.R.N.O. Contributions #38 Times of minima
No full textThis paper presents observations of eclipsing binaries acquired by members and cooperating observers of the Variable Star and Exoplanet Section of Czech Astronomical Society (B.R.N.O. observing project). Paper contains 3417 times of minima for 969 objects. It was obtained by 80 observers during 2011 – 2013 period. Some neglected southern eclipsing binaries and newly discovered stars by the observers of project B.R.N.O. are included in the list. New accurate ephemerides have been found for 447 binary systems. Time of primary minimum of long period variable eps Aur is presented as wellFil: Hoňková, K. Variable Star and Exoplanet Section of Czech Astronomical Society; República Checa. Observatory and Planetarium of Johann Palisa; República ChecaFil: Juryšek, J. Variable Star and Exoplanet Section of Czech Astronomical Society; República Checa. Observatory and Planetarium of Johann Palisa; República ChecaFil: Lehký, M. Variable Star and Exoplanet Section of Czech Astronomical Society; República Checa. Astronomical Society at Hradec Kralove; República ChecaFil: Šmelcer, L. Variable Star and Exoplanet Section of Czech Astronomical Society; República Checa. Valašské Meziříčí Observatory; República ChecaFil: Trnka, J. Variable Star and Exoplanet Section of Czech Astronomical Society; República Checa. City Observatory Slaný; República ChecaFil: Colazo, C. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; Argentina. Estación Astrofísica Bosque Alegre; ArgentinaFil: Guzzo, P. Estación Astrofísica Bosque Alegre; ArgentinaFil: Mina, Federico Daniel. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; ArgentinaFil: Quinones, C. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; ArgentinaFil: Taormina, M. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; ArgentinaFil: Melia, R. Observatorio Remoto Bosque Alegre; ArgentinaFil: Schneiter, Ernesto Matías. Estación Astrofísica Bosque Alegre; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Scavuzzo, Alan Martin. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; ArgentinaFil: Marcionni, M. Estación Astrofísica Bosque Alegre; ArgentinaFil: Tapia, L. Estación Astrofísica Bosque Alegre; ArgentinaFil: Fasseta, G. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; ArgentinaFil: Suarez, N. Universidad Nacional de Cordoba. Observatorio Astronomico de Cordoba; ArgentinaFil: Vilášek, M. Observatory and Planetarium of Johann Palisa; República ChecaFil: Rozehnal, J.. Štefánik Observatory; República ChecaFil: Kalisch, T. Variable Star and Exoplanet Section of Czech Astronomical Society; República Checa. Observatory and Planetarium of Johann Palisa; República ChecaFil: Lang, K.. Klokkerholm; DinamarcaFil: Gorková, S. ALTAN.Observatory; República ChecaFil: Novysedlák, R. Námestie sv. Martina; EslovaquiaFil: Salvaggio, F. Gruppo Astrofili Catanesi; ItaliaFil: Smyčka, T. Variable Star and Exoplanet Section of Czech Astronomical Society; República Checa. City Observatory Slaný; República ChecaFil: Spurný, M. Nejdlova 16; República ChecaFil: Wikander, T. Ornäs Backyard; República ChecaFil: Mravik, J. Slobodana Jajića 16; República ChecaFil: Šuchaň, J. Kraskova 12; EslovaquiaFil: Čaloud, J.. V Dolině 211; República Chec
Comparison of Gonadotropin-Releasing Hormone versus Estrogen-Based Fixed-Time Artificial Insemination Protocols in Grazing Bos taurus Suckled Beef Cows
No full textFixed-timed artificial insemination (FTAI) protocols for beef cattle in South America are primarily based on estradiol esters and intravaginal progesterone-releasing devices (IVPD). The objective of this study was to determine the optimal gonadotropin-releasing hormone (GnRH)-based protocol as an alternative to the use of estrogen-based protocols in grazing Bos taurus suckling beef cows. All cows received an IVPD on the day of protocol initiation and prostaglandin F2α (PG) plus equine chorionic gonadotropin (eCG) treatments at the time of IVPD removal. In Experiment 1, cows (n = 235) were randomly assigned to one of four treatments: (i) 7-day estradiol = 2 mg of estradiol benzoate (EB) at IVPD insertion on Day 9 and 1 mg of estradiol cypionate (ECP) at IVPD removal on Day 2; (ii) 7-day GnRH = 10 µg of GnRH at IVPD insertion on Day 10, IVPD removal on Day 3 and GnRH at FTAI; (iii) 7 & 7 estradiol = PG at IVPD insertion on Day 16, EB on Day 9 and ECP at IVPD removal on Day 2; (iv) 7 & 7 GnRH = PG at IVPD insertion on Day 17, GnRH on Day 10, IVPD removal on Day 3 and GnRH at FTAI. In Experiment 2, cows (n = 462) were randomly assigned to one of four treatments: (i) 6-day estradiol = EB at IVPD insertion on Day 9, IVPD removal on Day 3 and GnRH at FTAI; (ii) 7-day estradiol; (iii) 7-day GnRH; (iv) 7 & 7 GnRH. In Experiment 1, plasma progesterone concentrations and percentage of cows with a corpus luteum (CL) at IVPD removal, and pregnancy per AI (P/AI) were greater for cows subjected to GnRH-based protocols compared with cows subjected to estrogen-based protocols (p < 0.01). In Experiment 2, cows subjected to the 7 & 7 GnRH protocol had the greatest P/AI (p < 0.01). In summary, GnRH-based FTAI protocols resulted in similar or greater P/AI compared to estrogen-based FTAI protocols in grazing postpartum Bos taurus suckled beef cows. The greatest P/AI was attained with the 7 & 7 GnRH protocol.EEA BarrowFil: Ferre, Luis Bernardo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Barrow; ArgentinaFil: Jaeschke, J. Biogénesis Bagó; Argentina.Fil: Gatti, J. Biogénesis Bagó; Argentina.Fil: Baladón, G. Biogénesis Bagó; Argentina.Fil: Bellocq, E. Biogénesis Bagó; Argentina.Fil: Fernández, G. Actividad privada; Argentina.Fil: Rearte, Ramiro. Universidad Nacional de La Plata. Facultad de Ciencias Veterinarias. Instituto de Investigaciones en Reproducción Animal; ArgentinaFil: Kjelland, M.E. Mayville State University; Estados UnidosFil: Colazo, Marcos G. University of Alberta. Department of Agricultural, Food, and Nutritional Science; CanadáFil: Thomas, J. University of Missouri. Division of Animal Sciences; Estados Unido
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