scholarly journals 267 Supplementing Ca salts of soybean oil to late-gestating beef cows: Impacts on performance and physiological responses of the offspring

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 192-192
Author(s):  
Alice Brandão ◽  
Reinaldo F Cooke ◽  
Kelsey Schubach ◽  
Bruna Rett ◽  
Osvaldo Souza ◽  
...  

Abstract This experiment compared performance and physiological responses of the offspring from cows supplemented with Ca salts of soybean oil (CSSO) or prilled saturated fat (CON) during late gestation. Non-lactating, pregnant Angus × Hereford cows (n = 104) that conceived during the same fixed-time artificial insemination protocol, using semen from 2 sires, were used in this experiment. Cows were ranked by pregnancy sire, body weight (BW), and body condition score (BCS). On d 180 of gestation (d -15), cows were randomly assigned to receive (dry matter basis) 415 g of soybean meal per cow daily in addition to 1) 195 g/cow daily of CSSO (n = 52) or 2) 170 g/cow daily of CON (n = 52). Cows were maintained in 2 pastures (26 cows/treatment per pasture), and received daily 12.7 kg/cow (dry matter basis) of grass-alfalfa hay. From d 0 until calving, cows were segregated into 1 of 24 feeding pens thrice weekly and received treatments individually. Cow BW and BCS were recorded, and blood samples were collected on d -15 of the experiment and within 12 h after calving. Calf BW was also recorded and blood sample collected within 12 h of calving. Calves were weaned on d 290 of the experiment, preconditioned for 35 d (d 291 to 325), and transferred to a feedyard where they remained until slaughter. Upon calving, CSSO cows and calves had greater (P < 0.01) plasma concentrations of linoleic acid and total ω - 6 FA compared with CON cohorts. No differences in calf birth BW, weaning BW, and final preconditioning BW were noted (P ≥ 0.36) between treatments. Average daily gain and final BW in the feedlot were greater (P ≤ 0.05) in steers from CSSO cows compared with CON. The incidence of calves diagnosed with BRD that required a second antimicrobial treatment was less (P = 0.03) in calves from CSSO cows, resulting in reduced (P = 0.05) need of treatments to regain health compared with CON (Table 5). Upon slaughter, longissimus muscle area was greater (P = 0.03) in calves from CSSO cows compared with CON. Collectively, these results suggest that supplementing CSSO to late-gestating beef cows stimulated programming effects on postnatal offspring growth and Page 2 of 15 For Peer Review health. Therefore, supplementing late-gestating beef cows with CSSO appears to optimize offspring welfare and productivity in beef production systems.

2020 ◽  
Vol 98 (8) ◽  
Author(s):  
Alice Poggi Brandão ◽  
Reinaldo F Cooke ◽  
Kelsey M Schubach ◽  
Bruna Rett ◽  
Osvaldo A Souza ◽  
...  

Abstract This experiment compared the performance and physiological responses of the offspring from cows supplemented with Ca salts of soybean oil (CSSO) or prilled saturated fat (CON) during late gestation. Nonlactating, pregnant, multiparous Angus × Hereford cows (n = 104) that conceived during the same fixed-time artificial insemination protocol were assigned to this experiment. Cows were ranked by pregnancy sire (one of two sires), body weight (BW), and body condition score (BCS) on day −15 of the experiment (day 180 of gestation). Cows were then assigned to receive (dry matter basis) 415 g of soybean meal per cow daily in addition to: 1) 195 g/cow daily of CSSO (n = 52) or 2) 170 g/cow daily of CON (n = 52). Cows were maintained in two pastures (26 cows/treatment per pasture) and received daily 12.7 kg/cow (dry matter basis) of grass-alfalfa hay from day −15 to calving. Cows were segregated into 1 of 24 feeding pens three times weekly and received treatments individually from day 0 to calving. Calves were weaned on day 290 of the experiment, preconditioned for 35 d (day 291 to 325), and transferred to a feedyard, where they remained until slaughter (day 514). Cows receiving CSSO and their calves had greater (P < 0.01) plasma concentrations of linoleic acid and total ω-6 PUFA compared with CON after calving. Concentrations of immunoglobulin G in the colostrum and in calf plasma 24 h after birth were greater (P ≤ 0.02) in CSSO vs. CON cattle. Calves from CSSO cows had greater (P ≤ 0.05) expression of adipogenic (adipocyte fatty acid-binding protein and stearoyl-CoA desaturase) and myogenic (myogenic differentiation 1 and myogenin) genes in the longissimus muscle (LM) compared with CON. No treatment differences in birth BW, weaning BW, and final preconditioning BW were noted (P ≥ 0.36). Average daily gain and final BW in the feedyard were greater (P ≤ 0.05) in steers from CSSO cows compared with CON. The incidence of calves diagnosed with BRD that required a second antimicrobial treatment was less (P = 0.03) in calves from CSSO cows, resulting in reduced (P = 0.05) need of treatments to regain health compared with CON. Upon slaughter, LM area was greater (P = 0.03) in calves from CSSO cows compared with CON. Collectively, these results are indicative of programming effects on postnatal offspring growth and health resultant from CSSO supplementation to late-gestating cows. Hence, supplementing CSSO to beef cows during pregnancy might be a feasible alternative to optimize offspring productivity and welfare.


2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 51-52
Author(s):  
Alice Brandão

Abstract Option 1, Fetal Programming Only: Non-lactating, pregnant, multiparous Angus × Hereford cows (n = 104) were ranked by pregnancy sire (1 of 2 sires), body weight (BW), and body condition score (BCS) on d -15 of the experiment (d 180 of gestation). Cows were then assigned to receive: (1) 195 g/cow daily of CSSO (n = 52) or 2) 170 g/cow daily of CON (n = 52). Cows received treatments individually from d 0 to calving. Calves were weaned on d 290 of the experiment, preconditioned for 35 d, and placed in a feedyard until slaughter (d 514). Cows receiving CSSO and their calves had greater (P < 0.01) plasma concentrations ω-6 PUFA compared with CON after calving. Colostrum IgG and calf plasma IgG concentrations 24 h after birth were greater (P ≤ 0.02) in CSSO vs. CON cattle. Calves from CSSO cows had greater (P ≤ 0.05) expression of adipogenic and myogenic genes in the longissimus muscle compared with CON. No treatments differences in birth BW, weaning BW, and final preconditioning BW were noted (P ≥ 0.36). Average daily gain and final BW in the feedyard were greater (P ≤ 0.05) in steers from CSSO cows compared with CON. The incidence of calves diagnosed with BRD that required a second antimicrobial treatment was less (P = 0.03) in calves from CSSO cows, resulting in reduced (P = 0.05) need of treatments to regain health compared with CON. Upon slaughter, LM area was greater (P = 0.03) in calves from CSSO cows compared with CON. Collectively, these results are indicative of programming effects on postnatal offspring growth and health resultant from CSSO supplementation to late-gestating cows. Hence, supplementing CSSO to beef cows during pregnancy might be a feasible alternative to optimize offspring productivity and welfare. Option 2, Fetal Programming and Fat Tubs: Two experiments were conducted to evaluate: (1) effects of calcium salts of soybean oil (CSSO) supplementation to late gestating beef cows on the performance of the offspring; (2) the viability of utilizing low-moisture molasses-based blocks (LMB) as a delivery method for CSSO supplementation. In experiment 1, non-lactating, pregnant, multiparous Angus × Hereford cows were assigned to receive: (1) 195 g/cow daily of CSSO (n = 52) or (2) 170 g/cow daily of CON (n = 52) from d 195 of gestation until calving. CSSO cattle had greater (P < 0.01) plasma concentrations ω-6 PUFA; greater (P ≤ 0.02) colostrum and calf plasma IgG concentrations; greater (P ≤ 0.05) expression of adipogenic and myogenic genes in the longissimus muscle (LM); required fewer microbial treatments for BRD (P = 0.05) and had greater LM area compared to CON cohorts. In experiment 2, non-lactating, non-pregnant, multiparous beef cows were allocated to 1 of 9 pens (n = 9 pens; 4 cows/pen) and each pen was assigned to receive: 1) NOSUPP, hay only diet; 2) LMB, self-fed LMB supplement containing 24.7% DM CSSO; 3) CONC, hand-fed supplement identical to LMB. The design was a replicated 3 x 2 Latin square with 2 periods of 42 d, and a 21-d washout interval. Supplement DM intake did not differ (P = 0.39) between LMB and CONC cows from d 14 to 42 as designed, despite a greater variation in daily intake of LMB vs. CONC (treatment × day interaction; P < 0.01). No treatments effects were noted (P ≥ 0.40) for hay intake, BCS, and BW. From d 14 to 42, plasma concentrations of, ω-6 PUFA (P < 0.01) in CONC and LMB vs. NOSUPP cows. Hence, the use of self-fed LMB appears to be a valid strategy to provide CSSO to forage-fed beef cattle.


2020 ◽  
Vol 4 (2) ◽  
pp. 933-941 ◽  
Author(s):  
Alice Poggi Brandão ◽  
Reinaldo F Cooke ◽  
Kelsey M Schubach ◽  
Eduardo A Colombo ◽  
Giovanna N Scatolin ◽  
...  

Abstract This experiment compared plasma fatty acid (FA) profile of forage-fed beef cows receiving a molasses-based supplement enriched with Ca salts of soybean oil [CSSO; 24.7% of dry matter (DM)] via a self-fed low-moisture block (LMB) or hand-fed granular concentrate daily (CONC). Thirty-six nonlactating, nonpregnant, multiparous beef cows were blocked by age (three blocks), ranked within blocks by body weight (BW) and body condition score (BCS), and allocated to 1 of three drylot pens (27 × 10 m) per block. Nine pens with four cows each were enrolled in a replicated 3 × 2 Latin square design with two periods of 42 d, and a 21-d washout interval. On day 0, pens within each block were randomly assigned to receive one of the three treatments, in a manner that pens did not receive the same treatment in both periods (total n = 6 pens per treatment). Cows received hay (Cynodon dactylon), water, and a mineral–vitamin mix for ad libitum consumption during the study. Hay intake was recorded daily from days 0 to 42, and LMB intake was recorded from days 14 to 42 to allow cows to adapt to supplement with minimal interference from days 0 to 13. The CONC was offered at 0.420 kg/cow daily (DM basis) from days 0 to 13 and then adjusted (days 14 to 42) to match LMB intake. Cow BW and BCS were recorded, and blood samples were collected on days 0, 14, 28, and 42. Average LMB intake during the initial 13 d was 0.846 ± 0.107 kg/cow daily (DM basis). Supplement DM intake did not differ (P = 0.39) between LMB and CONC cows from days 14 to 42 as designed (0.570 vs. 0.583 kg/d, respectively; SEM = 0.011), despite a greater variation in daily intake of LMB vs. CONC (treatment × day interaction; P < 0.01). No treatments effects were noted (P ≥ 0.40) for hay intake, BCS, and BW. Treatment × day interactions were detected (P ≤ 0.01) for plasma concentrations of ω-6 polyunsaturated FA and total FA. On day 0, plasma FA profile did not differ (P ≥ 0.20) between treatments. From days 14 to 42, plasma concentrations of linoleic acid, ω-6 polyunsaturated FA, and total FA were greater (P < 0.01) in CONC and LMB vs. NOSUPP cows. Plasma concentrations of these FA were also greater (P ≤ 0.03) in LMB vs. CONC cows on day 14, but did not differ (P ≥ 0.35) on days 28 and 42. These results indicate that CSSO inclusion into LMB resulted in similar incorporation of ω-6 polyunsaturated and total FA in the circulation compared with CONC offered at the same daily rate. Hence, the use of self-fed LMB appears to be a valid strategy to provide CSSO to forage-fed beef cattle with reduced labor needs.


2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 295-295
Author(s):  
Alice Brandão ◽  
Reinaldo F Cooke ◽  
Kelsey Schubach ◽  
Eduardo Colombo ◽  
Giovanna Scatolin ◽  
...  

Abstract This experiment compared plasma fatty acid (FA) profile of forage-fed beef cows receiving a molasses-based supplement enriched with Ca salts of soybean oil [(CSSO); 24.7% of dry matter (DM)] via a self-fed low-moisture block (LMB) or hand-fed granular concentrate daily (CONC). Thirty-six cows were allocated to 1 of 9 drylot pens, which were enrolled in a replicated 3 x 2 Latin square design with 2 periods of 42 d. Pens were randomly assigned to receive 1 of the 3 treatments, in a manner that pens did not receive the same treatment in both periods. Cows received hay for ad libitum consumption during the study. Hay intake was recorded daily from d 0 to 42, and LMB intake was recorded from d 14 to 42. The CONC was offered at 0.420 kg/cow daily (DM basis) from d 0 to 13, and then adjusted (d 14 to 42) to match LMB intake. Average LMB intake during the initial 13 d was 0.846 ± 0.107 kg/cow daily (DM basis). Supplement DM intake did not differ (P = 0.39) between LMB and CONC cows from d 14 to 42. No treatments effects were noted (P ≥ 0.40) for hay intake, BCS, and BW. Plasma FA profile did not differ (P ≥ 0.20) between treatments on d 0. From d 14 to 42, plasma concentrations of linoleic acid, ω-6 polyunsaturated FA, and total FA were greater (P < 0.01) in CONC and LMB vs. NOSUPP cows. Plasma concentrations of these FA were also greater (P ≤ 0.03) in LMB vs. CONC cows on d 14, but did not differ (P ≥ 0.35) on d 28 and 42. Inclusion of CSSO into LMB resulted in similar incorporation of ω-6 polyunsaturated and total FA in the circulation compared with CONC offered at the same daily rate.


Author(s):  
Carole Lafreniere ◽  
Robert Berthiaume ◽  
Leo Giesen ◽  
Cheryl Campbell ◽  
Dale Gardner ◽  
...  

Pregnant beef cows (56; 727 ± 102 kg BW) in second trimester were used to examine black spruce (BSP) needles and branches for replacing alfalfa silage in wintering cow diets. Five dietary treatments assessed BSP inclusion rates (0, 15, 22.5, 30, 37.5% in the diet) for 92 days up until 2 weeks before start of calving using a randomized complete block design (10-12 cows/treatment). There were linear decreases (P < 0.001) in total weight gain, average daily gain (ADG) and dry matter intakes (DMI) as amounts of dietary BSP increased. Low DMI feeding BSP may be attributed to palatability issues and lower rates of digestion. Changes in body condition score (BCS) increased(P < 0.003) as dietary BSP increased. These effects are supported by corresponding linear decreases (P < 0.001) for changes in rump fat cover and increases (P < 0.001) in serum non-esterified fatty acids as dietary BSP increased. Post-feeding of test diets, there were no dietary treatment differences (P > 0.42) for calf birth and weaning weights and cow pregnancy and culling rates. Based on this study, incorporation of BSP into gestating cow diets cannot be recommended.


2019 ◽  
Vol 3 (4) ◽  
pp. 1162-1172
Author(s):  
Tassilo Brand ◽  
Martin Hünerberg ◽  
Tim A McAllister ◽  
Maolong He ◽  
Atef M Saleem ◽  
...  

Abstact: The purpose of this study was to evaluate the effect of a phytogenic feed additive (Digestarom [DA]; Biomin, Getzersdorf, Austria) on growth performance, feed intake, carcass traits, fatty acid composition, and liver abscesses of finishing steers. One hundred twenty Angus × Charolais crossbred steers (488 ± 26.5 kg) were used in a 110-d feeding experiment. Steers were blocked by weight and randomly assigned to 12 pens with 10 steers per pen. Each pen was allocated to one of three diets. Each diet contained 86.5% barley, 10.0% barley silage, and 3.5% vitamin and mineral supplement on a dry matter (DM) basis. The diets contained 0, 0.05, and 0.1 g DA/kg complete diet (DM basis), to achieve average daily DA intakes of 0 (control), 0.5 (LowDA), and 1.0 g (HighDA) per steer. Diets were prepared once daily and provided ad libitum. Two pens per treatment were equipped to record individual feed intake behavior. Steers were weighed every 28 d and carcass traits and liver scores were recorded at slaughter. Dry matter intake (average: 9.34 kg/d) did not differ (P &gt; 0.05) among diets. Average daily gain tended to increase linearly as DA increased (control: 1.82; LowDA: 1.87; and HighDA: 1.95 kg/d; P &lt; 0.09), but gain:feed ratio was not affected. Supplementation of DA affected longissimus muscle area quadratically (P = 0.05) with the largest area observed for LowDA. However, dressing percentage decreased linearly in response to increasing level of DA (P &lt; 0.01). Total abscessed livers were not affected, whereas proportion of severe liver abscesses was numerically lower with DA (30.8% and 42.5% for LowDA and HighDA) compared to the control (50%).


2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 129-130
Author(s):  
Gleise Medeiros da Silva ◽  
Tessa M Schulmeister ◽  
Federico Podversich ◽  
Federico Tarnonsky ◽  
Maria E Zamora ◽  
...  

Abstract A completely randomized design study with a 2 × 2 factorial arrangement of treatments evaluated the impact of artificial shade (SHADE or NO SHADE) and breed (ANGUS vs. BRANGUS) on performance of cows, nursing calves, and subsequent offspring. Twenty-four Angus and 24 Brangus black-hided pregnant cows (579 ± 8 kg BW; 6.5 yr; approximately 85 d of gestation) and their nursing calves were randomly allocated to 12 ‘Pensacola’ bahiagrass pastures (Paspalum notatum Flüggé; 1.3 ha; n = 4 pairs/pasture), with or without access to artificial shade (NO SHADE BRANGUS [NSB], NO SHADE ANGUS [NSA], SHADE BRANGUS [SB], and SHADE ANGUS [SA]) for 56 d during summer. Body condition score (BCS) of cows and BW of pairs were obtained on d -1, 0, 55, and 56 (weaning weight). Following weaning, calves were randomly allocated to 4 pens (n = 12/pen) equipped with GrowSafe feed bunks for 14 d to measure feed intake (DMI) and efficiency (G:F). A shade × breed interaction (P &lt; 0.05) was observed for average daily gain (ADG) and BCS of cows, with SB being greatest (P ≤ 0.05). Pre-weaning calf ADG tended to be greater (P = 0.10) for SHADE vs. NO SHADE. Weaning weight and BW 14-d post-weaning were lesser for NSB vs. NSA, SA, and SB, whereas no differences in DMI, ADG, or G:F were observed (P &gt; 0.11). Gestation length was greater for SHADE vs. NO SHADE cows (292 vs. 274; P = 0.02), but calf birth weight was not different. Providing artificial shade to pregnant-lactating beef cows positively impacted the growth of Brangus but not Angus cows. However, weaning BW of calves from Angus cows regardless of shade access did not differ from that of Brangus calves with shade. Further research should investigate the potential long-term effects of shade on the subsequent offspring.


2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 432-432
Author(s):  
Kelsey Harvey ◽  
Reinaldo F Cooke ◽  
Eduardo Colombo ◽  
Bruna Rett ◽  
Osvaldo Sousa ◽  
...  

Abstract Beef cows and their progeny were used to evaluate the effects of supplementing organic-complexed or inorganic Co, Cu, Mn, and Zn during gestation: on offspring reared as replacement heifers or feeder cattle. Non-lactating, pregnant beef cows (n = 190) were ranked by parity, pregnancy type, body weight (BW) and body condition score (BCS), at 117 ± 2.2 d of gestation (d 0) and assigned to receive a supplement containing: 1) sulfate sources of Cu, Co, Mn, and Zn (INR; n = 95) or 2) an organic complexed source of Cu, Mn, Co, and Zn (AAC; Availa®4; Zinpro Corporation, Eden Prairie, MN; n = 95). From d 0 to calving, cows were maintained in a single pasture and individually offered treatments three times a week. Calves were weaned at 6 mo of age (d 367) and preconditioned for 45-d. Heifer puberty status was verified weekly (d 437 to d 619) based on plasma progesterone concentrations. Steer calves were shipped to a commercial feedlot on d 493, where they were managed as a single group until slaughter (d 724). Plasma cortisol concentration was greater (P = 0.05) in AAC calves at weaning but tended to be less (P = 0.10) on d 370 compared with INR calves. Mean plasma haptoglobin concentration was greater (P = 0.03) in INR vs. AAC calves during preconditioning, and no treatment effects were noted (P = 0.76) for preconditioning average daily gain (ADG). Puberty attainment was hastened in AAC heifers during the experiment (treatment × day; P &lt; 0.01), despite similar (P = 0.39) ADG between treatments from d 412 to 620. No treatment effects were detected (P ≥ 0.24) for steer ADG from d 412 until slaughter, nor for carcass quality traits. Therefore, supplementing Co, Cu, Zn, and Mn as organic complexed instead of sulfate sources to beef cows during the last 5 mo of gestation did not improve performance of steer progeny until slaughter, but hastened puberty attainment in female progeny reared as replacement heifers.


2019 ◽  
Vol 4 (1) ◽  
pp. 159-169
Author(s):  
Jonathan C DeClerck ◽  
Nathan R Reeves ◽  
Mark F Miller ◽  
Bradley J Johnson ◽  
Gary A Ducharme ◽  
...  

Abstract One hundred forty-four cull cows (body condition score = 2.10 ± 0.61; BW = 456 ± 47 kg) were organized into a 2 × 2 factorial design (48 pens, 12 pens/treatment, and 3 cows/pen) to evaluate the effect of dietary roughage level and oral drenching of Megasphaera elsdenii NCIMB 41125 (M. elsdenii culture; Lactipro Advance; MS Biotec Inc., Wamego, KS) on performance and carcass characteristics. Cattle were finished over a 42-day realimentation period, and aggressively stepped up over a 10-day period to either a high roughage finisher (HRF; 25% roughage) or a low roughage finisher (LRF; 10% roughage). Within diet, cattle were administered no probiotic or 100 mL of M. elsdenii culture (M. elsdenii NCIMB 41125, 2 108 cfu/mL) on day 0. No diet × probiotic interactions were detected (P ≥ 0.15), suggesting that the magnitude of the response was not influenced by the concentrate level of the diet. The main effect of diet triggered several significant responses. Decreasing roughage level tended to improve average daily gain (ADG) by 9.7% (0.26 kg, P = 0.08), while decreasing dry matter intake (DMI) by 0.9 kg (P = 0.09), provoking a 19.7% enhancement of feed efficiency (0.036 units, P &lt; 0.01). However, interim data revealed declines of performance parameters among both diets with a significant difference between treatments only documented during the final phase of the realimentation period. During the final 14 days, LRF posted a 0.68 kg increase in ADG (P = 0.05) and a 2.0 kg decrease in DMI (P = 0.01), translating to improved feed efficiency (0.054 units, P = 0.03). This suggests that increasing the caloric density of finishing diets may help offset the regression of performance typically observed following a compensatory gain. No carcass traits were impacted by either diet or M. elsdenii culture (P ≥ 0.08). Overall, oral drenching of M. elsdenii culture tended to augment ADG (0.26 kg, P = 0.08) and carcass ADG (0.20 kg, P = 0.10). Implying that M. elsdenii culture was effective at alleviating the acidosis risk prompted by the rapid step-up period employed in the trial and may help capitalize on the narrow timeline of compensatory gain in cull cow realimentation.


2010 ◽  
Vol 62 (4) ◽  
pp. 868-874 ◽  
Author(s):  
F.H.M. Chizzotti ◽  
O.G. Pereira ◽  
S.C. Valadares Filho ◽  
L.O. Tedeschi ◽  
K.G. Ribeiro ◽  
...  

A trial involving a 2x2 factorial arrangement of treatments was conducted to evaluate two corn silage hybrids (Agromen, AGN35-A42) and (Bayer, A3663) and concentrate levels (25 and 50%) on animal performance. Twenty-four Holstein x Zebu crossbred steers, averaging 335±30kg of BW, were distributed in six randomized blocks to evaluate intake, digestibility, and performance. Treatments consisted of 75% corn silage A + 25% concentrate, 50% corn silage A + 50% concentrate, 75% corn silage B + 25% concentrate, and 50% corn silage B + 50% concentrate (dry matter basis); formulated to be isonitrogenous (13% crude protein, dry matter basis). There were no differences in the daily intakes of dry matter (DM), organic matter (OM), and crude protein. Additionally, there was a concentrate effect on non-fiber carbohydrates and total digestible nutrients intakes, and on total apparent digestibility of DM and OM, with higher intakes for steers fed diets with 50% of concentrate. However, average daily gain (ADG) was not influenced by treatments. The utilization of both corn silage hybrids in association with 25% of concentrate is a good option to feed crossbred steers with ADG close to 1.0kg in order to reduce diet cost.


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