bluuebunny/crossref_metadata_2025 huggingface dataset:
PSX-B-9 Effect of trace mineral sources in the supplement for grazing cattle on ruminal bacteria diversity
Authors: Cidrini Iorrano A , Ferreira Igor M , Oliveira Karla , Granja-Salcedo Yury , Lage Josiane F , Siqueira Gustavo , Resende Flavio
Published: October 2021

The rumen soluble Cu and Zn can affect the rumen microbial populations. This study aimed to evaluate the effect of trace mineral sources (Cu and Zn) in the supplement of grazing steers on ruminal bacteria diversity. Eight rumen cannulated Nellore steers (541 kg ± 18 kg BW) were distributed in a randomized block design in individual paddocks of Urochloa brizantha cv. Marandu. Steers were supplemented during 101 days between dry to rainy season at 5 g/kg BW with commercial supplement (25% CP) containing Cu (40 mg/ kg) and Zn (148 mg/kg) in the inorganic (Control) or hydroxy (HDX; Micronutrients Inc., IN) source. Samples of ruminal content were collected before supplementation at day 97 of experimental period and the total DNA extracted by commercial kit (Quick-DNA Fecal/Soil Microbe Miniprep). The V3/V4 regions of 16SrRNA gene was sequencing using the Illumina MiSeq, using the Quantitative Insights into Microbial Ecology (QIIME v.1.9.1) to filter reads and determine Operational Taxonomic Units (OTUs). Data were compared using an unpaired Wilcoxon test in R. A total of 293 OTUs were identified at genus level. The HDX resulted in a higher ruminal abundance of Corynebacterium 1 (P = 0.01), Prevotella 1 (P = 0.01), Lachnoclostridium 10 (P = 0.02), Lachnospiraceae AC2044 group (P = 0.03), Lachnospiraceae UCG-008 (P = 0.03), Streptococcus (P = 0.02), Ruminococcaceae UCG-010 (P = 0.01), Ruminococcaceae UCG-014 (P = 0.01), Ruminococcus 1 (P = 0.04), Coprococcus 1 (P = 0.04), Mogibacterium (P = 0.02), Selenomonas 1 (P = 0.02), Anaerovibrio (P = 0.03), Methylobacterium (P = 0.02), Treponema 2 (P = 0.02), Rikenellaceae RC9 gut group (P = 0.03), Ruminococcaceae; uncultured rumen bacterium (P = 0.02) and Eubacterium hallii group (P = 0.05), and lower abundance of Fibrobacter (P = 0.04), Butyrivibrio 2 (P = 0.05), Anaerotruncus (P = 0.03), Ruminiclostridium 5 (P = 0.03), Anaerorhabdus furcosa group (P = 0.02) and Erysipelotrichaceae UCG-004 (P = 0.01). The use of HDX in the supplement for grazing cattle between dry to rainy season increase the ruminal abundance of bacteria, mainly into Firmicutes phylum with important structural and non-structural carbohydrates degradation functions.
PSX-B-2 Effect of feedlot days on intake and performance of Nellore heifers
Authors: Ferreira Igor M , Cidrini Iorrano A , Souza William , Abreu Mateus I , Prados Laura F , Lage Josiane F , Siqueira Gustavo , Resende Flávio
Published: October 2021

The objective was to evaluate the effect of feedlot days (FD) on intake (DMI) and performance of Nellore heifers. Fifty-one Nellore heifers [325±19.3 kg of body weight (BW); 16±1 months], blocked by initial BW and stratified by carcass ultrasound, were divided into three treatments: 45, 75 or 105 FD; and placed in 18 pens [17 heifers/treatment; 6 pens/treatment (5 pens with 3 heifers and 1 pen with 2 heifers)]. The animals were fed ad libitum allowing 3% of refusals. The diet consisted of corn silage, ground corn, soybean meal, protected fat and minerals. The adaptation diet [16% CP and 79% TDN; roughage:concentrate (R:C) = 44:56] was offered from day 1 to 15 and the finishing diet from day 16 to 105 (14.5 % CP and 86% TDN; R:C = 25:75). At the end of each FD, heifers were weighted to obtain the shrunk final BW and slaughtered in the same slaughterhouse. The final BW and hot carcass weight (HCW) were greater (linear effect; P ≤ 0.01), respectively, for heifers on 105FD (442 and 244 kg) compared to 75FD (411 and 228 kg) and 45FD (374 and 206 kg). The DMI, backfat thickness and longissimus area increased over FD (linear effect; P ≤ 0.01; 45FD = 7.10 kg/d, 5.05 mm and 64.3 cm2; 75FD = 7.68 kg/d, 5.69 mm and 68.5 cm2 and 105FD=7.79 kg/d, 7.04 mm and 73.3 cm2). The FD did not affect carcass gain (P = 0.38) and feed efficiency based on carcass gain (P = 0.84). However, total carcass gain increased over FD (linear effect; P ≤ 0.01; 29, 51.4 and 75.9 kg, respectively to treatments 45, 75 and 105 FD). In conclusion, the feedlot days increase the BW, backfat thickness and longissimus area. However, the feed efficiency based on carcass gain does not reduce when the heifers are submitted for a long time on feedlot.
PSX-B-6 Effect of slow-release urea on gas production, fermentation characteristics, nutrient digestibility and microbial protein synthesis in an artificial rumen system
Authors: Guo Yongmei , Xiao Ling , Yan Sumei , Jin Long , Alexander Trevor , Yang Wenzhu
Published: October 2021

The objective of this study was to evaluate the effects of slow-release urea (SRU) on gas production, fermentation parameters, nutrient digestibility, and microbial protein synthesis using artificial rumen system. The experiment was a completely randomized design with four treatments and four replications of each treatment. The treatments were control diet (no SRU), control diet supplemented with 0.28% (U28), 0.56% SRU (U56) or control diet that was added by 1.5% more corn grain and substituted with 0.35% SRU for 1.85% soybean meal (U35-SBM). The diets were formulated to be isoenergetic (1.71 NEL Mcal/kg), but protein concentration was lower (15.48 vs. 16.24%) and starch concentration was higher (28.2 vs. 27.1%) with U35-SBM than other three treatments. Experimental period consisted of 8 d of adaptation and 7 d of sampling. Rumen inoculum was obtained from three ruminally fistulated Angus cows fed the same diet to the substrate incubated. Gas production (L/d) was lower (P = 0.02) with U35-SBM (1.51) than control (1.79) or U28 (1.92); however, methane production was not affected by treatments (average, 47 mg/d). Dry matter digestibility was greater (P < 0.01) with U35-SBM (78.5%) than other treatments (74.6%), which had no differences in DM digestibility. Total volatile fatty acid (VFA) production did not differ among treatments (average, 53.1 mmol/d), but increasing SRU supplementation linearly (P < 0.01) decreased molar proportion of propionate from 27.0 to 25.7% and linearly (P < 0.01) increased acetate to propionate ratio from 1.69 to 1.78. The ammonia nitrogen (N) linearly (P < 0.01) increased from 7.70 to 10.25 mmol/L with increasing SRU addition. Microbial protein synthesis was greater (P = 0.03) with SRU treatments (average, 83.9 mg N/d) than control (78.9 mg N/d). The present results demonstrated the benefits to add the SRU in dairy cow diet for improving ruminal digestibility and microbial protein synthesis.
PSX-B-1 Effect of exposure time and dose of effective microorganisms (EM®) on feed in vitro rumen fermentation and digestibility
Authors: Miranda-Figueroa Alain , Gutiérrez_Aguilar Carlos , González-Ronquillo Manuel , Romero-Pérez Atmir , Márquez-Mota Claudia Cecilia , Talamantes-Gómez José Moisés , Aviles-Nieto Jonathan , Vallejo-Hernández Laura , Corona Luis
Published: October 2021

The objective was to evaluate the effect of feed inoculation with effective microorganisms (EM®) (mainly containing Lactobacillus spp.,Rhodopseudomona palustrisand Saccharomyces cerevisiae) on rumen fermentation using in vitrogas production technique. We hypothesized that increasing doses and allowing exposure of EM® for up to 48 hours, would improve digestibility and rumen fermentation. The experimental design was a 4×4 completely randomized block design including 4 EM® levels [(0(EM0), 0.5(EM0.5), 1.0 (EM1) and 1.5 (EM1.5) mL EM® / kg DM] and 4 preincubation times [0 (T0), 12(T12), 24(T24), 48 (T48) h], with four repetitions per treatment. Treatments were evaluated using 100ml glass bottles with 0.5g of the diet (20% corn stover, 20% oat hay, 48.8% ground corn, 7% molasses, 1.2% urea, 1% soybean meal, 0.9% mineral premix,1.1% salt, dry matter basis) incubated with sheep ruminal fluid in 3 different occasions. Data were analyzed with PROC MIXED of SAS and orthogonal contrasts to determine the linear and quadratic effects of EM dose and exposure time. Interaction (P < 0.05) of EM x T was observed for in vitrodry matter digestibility (IVDMD), maximum gas volume (Vmax), total volatile fatty acids (VFA), acetate (ACE), propionate (PROP), butyrate (BUT) and ammonia-nitrogen (NH3), IVDMD was higher (P < 0.01, 4.8 and 3.72%) for T48EM1.5 than T12EM0 and T0EM0, PROP was higher (P < 0.05) for T48EM0, T48EM1 and 1.5 than T12EM0. The ACE:PROP ratio was higher (P < 0.05, 17.2%) for T12EM0 than T48EM1.5. IVDMD, PROP and NH3 linearly increased (P < 0.01) with increasing exposure time. EM levels have a quadratic effect (P < 0.01) with maximum response at EM0.5. It was concluded that the addition of 0.5 to 1.5 mL/kg DM of EM® to a sheep diet and increasing preincubation time, up to 48h, improve feed fermentation and digestibility.Project was supported by UNAM, DGAPA, PAPIIT (IT202120).
PSX-B-3 Effect of infrequent nitrogen supplementation on forage utilization
Authors: Bowhay Ciana , Wickersham Tryon
Published: October 2021

Our objective was to determine the effects of differing levels of supplemental nitrogen offered daily, or every 3 d on nitrogen balance, forage intake, and digestibility in cattle consuming low-quality forage. Five ruminally cannulated Angus × Hereford steers (BW = 350 ± 71 kg) were used in a 5 × 5 Latin square design. Steers consumed low-quality bluestem hay (67.7% NDF, 4.7% CP; DM basis) ad libitum. Treatments were no supplement (CON), or cottonseed meal offered at levels providing 120 mg N/kg BW each day (L/1D) or every 3 d (L/3D), 240 mg N/kg BW every 3 d (M/3D), or 360 mg N/kg BW every 3 d (H/3D). Hay, ort, urine, and fecal samples were collected during the last 6 d of each period and ruminal fluid during the last 3 d. Total digestible OM intake was greater in L/1D (6660 g/d; P < 0.01) compared to CON (4498 g/d) and increased linearly in steers supplemented intermittently (5145, 6170, and 6698 g/d for L/3D, M/3D, and H3/D, respectfully; P < 0.01). Total tract OM digestibility was similar between CON and L/1D, L/3D, and H/3D (58.21, 61.21, 60.82, and 60.91%, respectively; P ≥ 0.10) but was greater in M/3D steers (63.30%; P ≤ 0.02). Reducing frequency of protein supplementation to every 3-d improved forage intake and utilization similar to daily supplementation when provided at medium (240 mg N/kg BW) or high (360 mg N/kg BW) levels. Improved efficiency of nitrogen recycling likely buffered disruptions in protein supply, maintaining intake and digestibility of low-quality forage without daily supplementation. Supplementation of protein every 3 d at 240 g N/kg BW appears to the most biologically effective strategy, increasing intake of LQF and maximizing OM digestibility and N utilization.
PSXIII-3 Effects of mineral source and additive in mineral supplementation on productive performance of growing beef cattle on tropical pastures
Authors: de Carvalho Victor Valério , Perdigão Alexandre , Vasconcellos Guilherme S F M , Acedo Tiago S
Published: October 2021

Our objective was to evaluate the effects of mineral supplementation using the association of carboaminophosphochelates as mineral source plus Salinomycin on grazing beef cattle performance during growing phase. A total of 80 Nellore bulls (IBW = 292.72 ± 13.55 kg; Age, ~13 mo) were distributed in 8 paddocks (~2.7 hectares each) planted with Palisade Grass cv. Xaraés during the rainy to rainy-to-dry transition seasons (February to May). The experiment was a randomized complete block design (10 animals/paddock, 4 paddocks per treatment). The mineral supplementation was provided ad libitum and treatments were: Control; Mineral supplementation containing inorganic minerals, and TM+Salinomycin = Mineral supplementation containing carboaminophosphochelates (TM, Tortuga® Minerals) as minerals source (Cr, Se, Zn, Mn, S, Cu e Co) plus Salinomycin (~108 mg per animal/day). The supplement orts were removed and weighted daily to calculate supplement intake. The animals were weighed after a 14 h-fasting at the beginnig and end of the trial (84 days) to calculate weight gain. The paddock was considered the experimental unit and data were analyzed using PROC MIXED of SAS, whereby means were separated using the PDIFF statement (P < 0.05). Supplement intake was similar between treatments (P = 0.13). Animals supplemented with TM+Salinomycin tended to have greater final BW (358 vs. 347, P = 0.07) and increased ADG in 22,3% (0.730 vs. 0.597 kg/d, P = 0.03) compared with animals fed Control. In conclusion, the combination of carboaminophosphochelates minerals plus salynomicin improves grazing beef cattle weight gain, with no deleterious effect on mineral supplement intake.
PSXIII-2 Effect of varying proportions of cereal rye and turnip on ruminal fermentation and methane output through in vitro batch culture
Authors: Cox-O’Neill Jordan L , Fellner Vivek , Franluebbers Alan J , Harmon Deidre D , Poore Matt H , Eisemann Joan , Pickworth Carrie L
Published: October 2021

Ruminant animal performance has been variable in studies grazing annual cool-season grass and brassica monocultures and mixtures. There is little understanding of the fermentation mechanisms causing variation. The aim of this study was to determine apparent dry matter (DM) digestibility, methane, and volatile fatty acid (VFA) concentration from different proportions of cereal rye (Secale cereal; R) and turnip (Brassica rapa L.; T) (0R:100T, 40R:60T, 60R:40T, and 100R:0T) via in vitro batch fermentation. Freeze-dried forage samples from an integrated crop-livestock study was assembled into the four treatments with a 50:50 leaf to root ratio for turnip. Measurements were made following a 48 hr fermentation with 2:1 buffer and ruminal fluid inoculum. Data were analyzed using Mixed Procedure of SAS with batch (replicate) and treatment (main effect) in the model; differences were declared at P ≤ 0.05, with tendencies declared at > 0.05 but < 0.10. Rumen apparent DM digestibility (26.8%; overall mean) was not different among treatments. Methane production was less (P < 0.01) with inclusion of turnip ranging from 774 nmol/ml for 0R:100T to 1416 nmol/ml for 100R:0T. Total VFA production, acetate to propionate ratio, acetate, and valerate were not affected by forage treatments (117 mM, 1.45, 39.84 mol/100 mol, and 7.86 mol/100 mol, respectively; overall mean). Propionate, isobutyrate, and isovalerate concentrations were greater and butyrate concentration less with greater (P < 0.01) proportions of rye in the mixture. No effect of R:T ratio on digestibility or total VFA production along with the observed differences in individual VFA concentration do not explain variable response in grazing animals. Additionally, methane production results indicate that grazing turnips could potentially reduce methane production and thus reduce ruminant livestock’s contribution to greenhouse gas emissions.
PSXIII-12 Exploring nutritional differences of canola seeds and bio-processing co-products (meals, pellets) from different processing plants/companies in Canada and China for dairy cattle
Authors: Oliveira A , Yu P
Published: October 2021

Canola was created as a low erucic acid and low glucosinolate seed, to produce high quality oil for human consumption and meal for use in livestock feed. China is an important user of Canadian canola products (seeds, oil, and meal). The extraction of the oil from the seed produces a co-product called canola meal. This meal is rich in protein and is used as a protein source in animal diets. However, differences in the characteristics of the seeds, or processing methods during oil extraction may affect the quality of this co-product. Plus, the synthesis of tissues and milk is related to the amino acids available to the animal for absorption in the small intestine. This study aimed to determine if there are significant differences in the intestinal digestibility (in vitro) of CP and DM between canola seeds and meals from different companies in Canada and to determine if there are significant differences between them in Canada and China. The three-step procedure was applied on residues from a 12-hour rumen incubation in fistulated dairy cows to estimate the intestinal digestibility of CP and DM. There were significant differences (P < 0.05) for TDDM (Total digestible dry matter) and IDP (intestinal digestibility of protein) of the meals between countries. The samples from China had higher TDDM (83.76% versus 81.53%, P = 0.018), while Canada’s had higher IDP (68.51% versus 65.28%, P = 0.016). No significant differences were observed within countries. Based on the material analyzed during this study, it is safe to affirm that there are no significant differences in the digestibility of DM and CP between Canada and China. It was concluded that the quality of the canola seeds or meals produced in both Canada and China were similar when used in dairy rations.

Key words: canola seeds and bio-processing co-products (meals, pellets), nutritional differences, dairy cows
PSXIII-10 Effects of nitrate concentration in drinking water on water and feed consumption, total tract digestibility and health implications in Holstein bulls fed high-concentrate diets
Authors: Verdú Marçal , Marti Sonia , Riera Joan , Medinya Carles , Cucurull Jordi , Devant Maria
Published: October 2021

The aim of this study was to evaluate the effect of nitrate concentration in drinking water on water and feed consumption, total tract apparent digestibility and its potential toxicity on animal health in fattening Holstein bulls. Twenty-four Holstein bulls (161 ± 19.9 kg of initial BW, and 183 ± 25.3 d of age) were housed individually and fed ad libitum. Animals were assigned to 4 treatments according to nitrate concentration in drinking water: 0, 44, 110 and 220 mg / L. The different nitrate concentrations were achieved by the addition of different potassium nitrate 0.22 M doses. Water consumption and animal health status was recorded daily. Every 2 wks feed consumption, BW were recorded, and nitrate concentration in drinking water was analyzed by photometry. At d 0, 14, 112 and 168 blood samples were collected to determine ammonia and methemoglobin concentrations. At d 14 and 168 total tract apparent digestibility was estimated. Data were analyzed with a mixed effects model. Water consumption decreased (P < 0.05) when nitrate concentration in water was above ≥ 110 mg / L (30.2, 27.4, 24.4 and 26.4 ± 1.38 L/d for 0, 44, 110 and 220 mg/L nitrates in water, respectively). Water nitrate concentration did not affect serum ammonia and methemoglobin concentration (58.0 ± 2.17 µmol / L and 2.4 0.09 %, respectively). In addition, water nitrate concentration did not affect performance, total DMI, and nutrient digestibility. Drinking water for a long period with nitrate concentrations up to 110 mg/L did not have detrimental effects on performance and health. Beyond this threshold a reduction of water consumption of 16 % was observed and blood parameters (methemoglobin) and health registers did not indicate that the concentration of 220 mg/L of nitrates in drinking water may have health side-effects in fattening bulls fed high-concentrate diets.
PSXIII-8 Effects of different sources of Zn on in vitro ruminal fermentation and digestibility of a lactation diet
Authors: Boyer Angela R , Jiang Yun , Blakeney Alon , Nuzback Dennis , Humphrey Brooke , Garcia Miriam
Published: October 2021

Vistore® minerals are hydroxychloride minerals that feature high metal content and improved bioavailability. This study was conducted to compare different sources of zinc (Zn) on in vitro rumen fermentation parameters. Three ruminally-cannulated Jersey heifers were adapted to a lactation diet for two weeks before used as donors. Three sources of Zn were tested at 20 ppm: No supplemental Zn (CON), ZnSO4, Vistore Zn, and another Zn hydroxychloride (Vistore-competitor). The concentration of Zn in this study was selected from a titration study (0 to 40 ppm ZnSO4) to identify the minimum concentration of ZnSo4 affecting rumen fermentation. The lactation diet (TMR) was dried and ground to 1mm and used as substrate. Rumen fluid was collected two hours after feeding. Substrate (0.5 g) was inoculated with 100 mL of 3:1 McDougall’s buffer: ruminal flued mixture at 39ºC for 24 h. Each treatment was run in triplicate and in three runs. Data were analyzed with R 3.0. The model included fixed effect of treatment and random effect of run. ZnSO4 reduced (P < 0.05) maximum gas production, DMD (54 vs. 55.9%) and cellulose (27.5 and 40.7%) digestibility. acetate to propionate ration (2.20 vs. 2.24) and NH3-N concentration (6.0 vs. 7.0 mg/dL), increased (P < 0.05) propionate % (27.2 vs 26.7%) compared to control. Vistore had higher pH than control (6.44 vs. 6.40, P = 0.02) but did not affect other parameters compared to CON. Vistore-competitor reduced total VFA production compared to control, ZnSO4, and Vistore (94 vs. 102, 106 and 107 mM, respectively, P = 0.01) but did not affect other parameters. In general, Vistore Zn maintained in vitro ruminal fermentation and digestibility, while ZnSO4 had negative effects on both fermentation and digestibility and Vistore-competitor reduced total VFAs. Results indicate hydroxychloride minerals may stabilize rumen parameters versus sulfate sources but different hydroxychloride sources appear to influence rumen parameters differently.
PSXIII-6 Effects of cyclic monensin feeding on ruminally cannulated beef steers consuming low-quality forage
Authors: Bell Natasha L , Gonzalez Daisy A , Hook Kayla
Published: October 2021

The loss of monensin efficacy when fed continuously requires further study for development of novel feeding strategies that may prolong its effectiveness. In the present study, effects of cyclic monensin feeding on utilization of low-quality forage (LQF; 4.9%CP) were evaluated using ruminally cannulated steers (12 Bos taurus; 260 kg BW). Steers were randomly assigned to one of three treatments: 1) CON (0 mg∙hd-1∙d-1 monensin; Rumensin® 90, Elanco Animal Health, Greenfield, IN), 2) MON (200 mg∙hd-1∙d-1 monensin) or 3) CYC (200 mg∙hd-1∙d-1 monensin for 14 d and 0 mg∙hd-1∙d-1 monensin for subsequent 14 d). Dried distillers grains (1 kg∙hd-1∙d-1) were fed for monensin inclusion. Each of four periods were 28 days in length. Hay, ort, and fecal samples were collected d 10–14 of each period for measures of digestion. Rumen fluid was collected with a suction strainer 0, 2, 4, 8, and 12 h after feeding on d 14 for VFA analysis. Data were analyzed using the MIXED procedure of SAS 9.4 (SAS Inst. Inc., Cary, NC). A period × treatment interaction was not observed for any measure of digestion (DMD, OMD, NDFD; P ≥ 0.39). A period × treatment interaction (P < 0.01) was observed for acetate, propionate, and A:P. An hour effect was observed for all ruminal fermentation parameters (acetate, propionate, A:P ratio, total VFA; P ≤ 0.01). No treatment effects or interactions were observed for any ruminal fermentation parameters by period 4 (P ≥ 0.15), but an hour effect was observed for all parameters (P ≤ 0.03) in period 4. Exploration of novel feeding strategies results in knowledge beef cattle producers can apply in their operations. This data is particularly relevant in cow-calf operations where LQF is often consumed. Although cyclically feeding monensin was similar to continuous feeding, this research furthers our knowledge and understanding of monensin.
PSXIII-15 Impact of forage allowance on performance and reproductive parameters in Nellore heifers
Authors: Ferreira Igor M , Cidrini Iorrano A , Oliveira Karla , Sousa Luciana , Prados Laura F , Moretti Matheus , Siqueira Gustavo , Resende Flávio
Published: October 2021

The objective was to evaluate the effects of forage allowance on the performance and pregnancy rate of Nellore heifers submitted to the fixed-time artificial insemination (FTAI) at 14±1 months. The experimental period was divided into the growing phase (GP; 173d) and breeding season (83d). Ninety weaned Nellore heifers [169±19 kg of body weight (BW); 210±28 days of age] were blocked by initial BW and randomly assigned to receive different forage allowance: (1) High (HFA; 7.17 kgDM/kgBW; and (2) Low (LFA; 3.27 kgDM/kgBW); and divided into 6 paddocks (2.15 to 2.4 ha each one). The grazing method used was continuous stocking with a variable stocking rate where treatment conditions were established varying the stocking rate on pasture (put-and-take). The supplement consisted of corn, soybean meal, urea, monensin, sodium chloride and minerals mix (80% TDN and 24% CP) and was provided daily (ad libitum; expected intake around 1% of BW). The final pregnancy rate was determined after two FTAI (d256). Heifers BW at the end of the GP was greater (P < 0.01) for HFA vs. LFA (268 vs. 255 kg). The overall average daily gain (ADG) was greater 68 g/d for animals maintained in HFA than LFA (P < 0.01; 0.713 vs. 0.645 kg/d). Supplement intake (kg/animal/d) had no treatment effect (P = 0.117). On d173, forage allowance affected (P < 0.01) the backfat thickness obtained by real-time carcass ultrasound (HFA = 3.08 vs. LFA = 2.85 mm). The pregnancy rate had no treatment effect (P = 0.223; on average 61%). However, the pregnant heifers per hectare had treatment effect (P = 0.036; HFA = 3.78 vs. LFA = 2.72 pregnant heifers/ha). In conclusion, the low forage allowance reduces the animal performance and affects the carcass composition but provides a greater number of pregnant heifers per hectare.
PSXIV-5 Methionine supply during mid-gestation affects offspring birth weight in a sex-dependent manner in beef cattle
Authors: Gouvêa Vinícius N , Smithyman Mackenzie M , Bagheri Naghme , Batistel Fernanda
Published: October 2021

In previous studies with dairy cattle, methionine supply during late-gestation enhanced cow feed intake and affected calf growth in utero and postnatally. Our objective was to investigate how methionine supply during mid-gestation, phase where the secondary myogenesis occurs, alters heifers’ plasma concentration of amino acids and offspring’ birth weight in beef cattle. Forty purebred Angus heifers were blocked by expected parturition day and blocks were balanced by sire, body weight, and body condition score. Heifers were randomly assigned to a basal diet with no added methionine (Control) or the basal diet plus a commercial source of rumen-protected methionine (Methionine). The methionine source was dosed to deliver 6 grams of metabolizable methionine daily. Heifers received the treatments from day 90 to 180 of gestation, and all heifers were pair-feed during early- and late-gestation. Heifers’ plasma samples were collected on day 180 of gestation. Data were analyzed using mixed models. The model for plasma samples included the fixed effect of treatment and the random effect of block, while the birth weight model included the fixed effect of treatment, sex, and its interaction and the random effect of block. Plasma concentrations of insulin, glucose, and urea were not affected by treatments (P ≥ 0.20). Dietary supply of methionine increased plasma concentration of methionine (P < 0.01), and decreased glycine and serine (P < 0.01). None of the other essential and non-essential amino acids were affected by treatments (P ≥ 0.12). Heifers supplemented with methionine had a greater plasma concentration of the antioxidant taurine than control heifers (P = 0.04). A treatment × sex interaction was observed for calf birth weight; methionine-fed heifers delivered heavier male calves than control-fed heifers (P = 0.03). No treatment or sex effect was observed for calf birth weight (P ≥ 0.18). Our preliminary results indicate that methionine supply during mid-gestation affects fetal growth in beef cattle in a sex-dependent manner.
PSXIV-1 In vitro evaluation of methane mitigation using monensin and ammonium nitrate in beef cattle diets
Authors: Tarozo Ana Paula , Gomes Lobo Annelise Aila G , Peña Bermudez Yuli Andrea A , Moreno Danny Alexander Rojas , Spalato Rafaela Zuliani , de Freitas Rafaela Scalise Xavier , Da Silva Bueno Ives Claudio C
Published: October 2021

Currently, the use of feed additives appears as an alternative in reducing the environmental impact of animal agriculture, reducing the emission of greenhouse gases and increasing the acceptability of exports in international trade. Thus, the objective of the present study was to evaluate the in vitro rumen fermentation parameters by adding 4.5% ammonium nitrate and 30 ppm of the additive sodium monensin to beef cattle diets, searching for the best alternative to mitigate methane production. The experiment was performed in an in vitro gas production system, and the fermentation kinetics, methanogenesis and short-chain fatty acid (SCFA) production were studied. Regarding methanogenesis, it was observed that the diet with ammonium nitrate showed higher in vitro degradability in DM (P = 0.017) and lower methane production (in ml/g of DM; P = 0.0088), compared to the diet with sodium monensin. Considering the fermentation kinetics, it can be stated that acetate production in molar (%) was lower in control and monensin diets, and higher in nitrate and nitrate + monensin diets (P < 0.0001). It is concluded that both treatments ammonium nitrate + sodium monensin and ammonium nitrate alone have mitigating effect on methane emission, when compared to the control treatment. However, ammonium nitrate is more effective in this regard, producing less methane in vitro and having no negative effect on rumen fermentation parameters.
PSXIV-15 The effects of body condition score on the milk production and energy balance of transition dairy cows
Authors: Hao YangYi
Published: October 2021

Our objective was to evaluate the effects of body condition score (BCS) on the milk production and energy balance of transition dairy cows. Seventy-five multiparous dairy cows were separated into four groups according to the BCS, HH (4.25 ± 0.23 and 3.35 ± 0.19 BCS, pre and postpartum, respectively, n = 17), HM (4.14 ± 0.15 and 2.92 ± 0.24, n = 19), MM (3.10 ± 0.21 and 2.78 ± 0.17, n = 23), ML (2.88 ± 0.23 and 2.46 ± 0.19, n = 16). The milk yield, rumen pH, etc., data were collected and analyzed using a one-way ANOVA model in SAS (SAS version 9.4, SAS Institute Inc., Cary, NC, USA). The ML group had a higher milk yield and total solid yield than the MM group (P < 0.05), while the HH and HM groups had no difference with other groups. The HM and ML groups had a higher milk fat content than the MM group (P < 0.05), while the HH group had no difference with other groups. Milk protein content in the HH group was higher than the ML group (P < 0.05). The milk lactose, total solids, urea content in these groups had no difference. The ML group had a higher milk acetone content than the HH group (P < 0.05). The BCS change in the HH and HM groups was higher than the MM and ML groups, and that in the ML group was higher than the MM group (P < 0.05). The rumen pH had no difference within these groups. These findings collectively indicated the prepartum dairy cow with middle BCS would have a more efficient body fat utilization and a better milk production performance. Furthermore, reducing body fat loss is necessary to avoid the negative energy balance.
PSXIV-13 Supplemental essential oil blends plus 25-hydroxy-vitamin-D3 improve carcass characteristics in cattle finished under tropical conditions
Authors: Mendoza-Cortés Daniel , Arteaga-Wences Yesica , Félix-Bernal Adrián , Estrada-Angulo Alfredo , Castro-Pérez Beatriz , Ríos-Rincón Francisco , Urías-Estrada Jesús , Franco Manuel , Vasconcellos Guilherme S , Acedo Tiago S , de Carvalho Victor Valério , Perdigão Alexandre , Plascencia Alejandro
Published: October 2021

A total of 90 young crossbreed bulls (initial weight=228.04±7.06 kg) were used in a 171-day feeding trial in order to evaluate the combination of supplemental blend of essential oils (Crina® Ruminants; DSM Nutritional Products) plus 25-hydroxy-vitamin-D3 (HyD®, DSM Nutritional Products; EO+HyD) on growth performance and carcass characteristics in cattle finishing under tropical conditions. Cattle were blocked by weight into 2 blocks and randomly allocated to 2 treatments (9 pens/treatment, 5 bulls/pen). Cattle were fed with a steam-flaked corn-based diets (average diet NEm= 1.95 Mcal/kg during first 84-d, and 2.15 Mcal/kg during the remaining 87-d). Treatments consisted of: 1) EO+HyD supplementation along fattening period (171-d), or 2) supplementation with monensin (Rumensin®, Elanco Animal Health; 20 mg/kg diet) during the first 84-d and monensin (20 mg/kg diet) plus virginiamycin (Stafac®, Phibro Animal Health; 20 mg/kg diet) during remaining time (87-d). The average THI during course of the experiment was 76.67±2.7 with a maximum of 85.46±2.2 and minimum of 68.29±2.6. There were no statistical differences (P > 0.10) between EO+HyD and ionophores/antibiotic supplemented cattle on DM intake (7.575 vs 7.534 kg/d), average daily gain (1.433 vs 1.406 kg), or gain-to-feed ratio (0.189 vs 0.187). However, cattle fed with EO+HyD tended (P = 0.07) to have heavier carcass weight in 5.2 kg (304.9 vs 299.7 kg), showed greater LM area (89.89 vs. 82.77 cm², P < 0.01) and greater estimated retail yield (1.6%, P = 0.02) than cattle receiving ionophores/antibiotic mixture. Cattle receiving EO+HyD showed more percentage of carcass classified as Choice (14.28 vs 13.33%) and “Select” (59.52 vs 44.44%) and lower percentage of carcass classified as “Standard” (26.20 vs 42.23%). The combination of a blend of essential oils plus 25-hydroxy-Vit-D3 (EO+HyD) in finishing phase improve carcass characteristics. Supplemental EO+HyD is a viable alternative to supplemental monensin, or monensin plus virginiamycin used in growing-finishing diets for feedlot cattle.
PSXIV-2 Influences of glycerol and bypass fat supplementation on performance of early fattening Hanwoo steers under heat stress
Authors: Ryu Gyeonglim , Woo Junsik , Song Geun Hong , Oh Young Kyoon , Park Keun Kyu
Published: October 2021

This study was conducted to determine the influence of glycerol and bypass fat supplementation on growth performance of early fattening Hanwoo steers under heat stress. Thirty-six Hanwoo steers were randomly allocated into 4 treatments based on BW and age for 112 days from the beginning of July to the end of October 2020. Experimental treatments were divided into four by the type of energy supplements: Control (CP, 14%; TDN 71.9), glycerol addition (GL; CP, 14%; TDN 74.9), bypass fat addition (BF; CP, 14%; TDN 74.9), and glycerol plus bypass fat additive (GL+BF; CP, 14%; TDN 74.9). During the experimental period, automatic temperature-humidity recorders were used for measuring every 10 minutes in the pen. The temperature-humidity index (THI) range of the 1st and 2nd periods was recorded above the threshold (THI 75~77) level based on the Korean beef heat stress index, and the average THI of the 2nd period was 79.91, being the mild-moderate (THI 78~81) level. The dry matter intake (DMI) and average daily gain (ADG) did not show significant differences in all treatments during the whole period. The feed conversion ratio (FCR) during 1st and 2nd periods showed the same pattern because FCR is related to DMI and ADG. Additionally, the rectal temperature showed no significant difference in all treatments, but a significant difference in each period (P < 0.05). The results demonstrated that early fattening Hanwoo steers under mild-moderate stress did not affect DMI and productivity but 9.8% of GL or 1.9% BF in a concentrate only could be included in Hanwoo steers diets without decreasing palatability. In addition, increasing the energy content in the feed by 5% did not lead to a difference in productivity. Further studies would be needed on the effect of increasing the energy density on productivity under more severe thermal stress conditions.
PSXIV-7 Performance and environmental benefits from biochar supplementation in beef cattle grazing systems
Authors: Conlin Emily , Lardner Herbert , Ellis Jennifer L , Mandell Ira B , Wood Katharine M
Published: October 2021

Reducing greenhouse gas (GHG) emissions from beef cattle production systems has continuously been recognized as an important strategy to help mitigate climate change. This experiment was conducted to determine the optimum inclusion level of biochar (Oregon Biochar Solution, White City, OR) in the diet to reduce enteric methane (CH4) emissions from beef cows. Biochar is a stable form of carbon produced through low-oxygen and high-temperature pyrolysis of organic matter (typically forestry waste). Using a 4 x 4 Latin square design, pregnant beef cows (n = 8) of similar weight and stage of pregnancy were supplemented with biochar daily at 0, 1, 2, or 3% of total dry matter intake (DMI). Biochar was added to a pellet containing 45% biochar, 42.5% wheat midds, 10% canola oil, and 2.5% dry molasses to facilitate ease of feeding and encourage biochar consumption. Each 21-day period consisted of 14 days for diet adaptation and 7 days for data collection. Enteric gas emissions were measured using C-Lock GreenFeed trailers (C-Lock Inc., Rapid City, SD, USA) and DMI was collected using Insentec feeders (Insentec, Voorsterweg, The Netherlands). Enteric CH4 emissions expressed in g CH4/day, g CH4/kg DM, and g CH4/kg BW were not affected by biochar supplementation (P ≥ 0.41), although the 3% inclusion was numerically lowest. For all parameters expressing CH4 emissions, linear and quadratic effects for inclusion rate were not significant (P ≥ 0.19). Dry matter intake and cow body weights were not affected by biochar supplementation (P ≥ 0.34). These results suggest that biochar was ineffective for reducing CH4 emissions from beef cows fed a high forage diet (50% haylage, 30% straw, 17% corn silage) with no effects on animal performance. Further research should investigate whether type of biochar or higher inclusion levels of biochar can reduce CH4 emissions from beef cattle.
PSXIV-14 Supplementation of high-grain diet with red osier dogwood affects in vitro digestibility and fermentation characteristics
Authors: Yang Wenzhu
Published: October 2021

Red osier dogwood (ROD) is a native shrub plant rich in phenolic compounds with antimicrobial properties. The objective of this study was to evaluate the effects of substituting barley silage with either raw ROD or ROD extract (RODE) in high-grain (HG) diet under a low media pH (5.8) on gas production (GP), dry matter (DM) disappearance (DMD) and fermentation characteristics in batch cultures. The study was a completely randomized design with 4 treatments: 1) control diet (10% barley silage and 90% barley concentrate, DM basis), control diet supplemented with 2) monensin (30 mg/kg diet DM; positive control), 3) substitution of 3% ROD or 4) 3% RODE for an equal portion of silage. Inoculum was obtained from 2 ruminally fistulated beef heifers offered the HG diet. Substrate ground (1 mm) was incubated for 24 h and the experiment repeated twice. The GP did not differ among treatments (147 ml/g DM), but the DMD differed (P < 0.02) at highest for control (69.4%), lowest for ROD (58.4%) and intermediate for other treatments (64.1%). Total volatile fatty acid (VFA) concentration (mM) tended (P< 0.08) to be lower with ROD (80.5) and monensin (80.1) than control (83.9). Acetate proportion was greater (P = 0.02) with ROD (46.2%) and RODE (46.9%) than control (42.4%) and monensin (42.3%). However, the propionate proportion was greater (P = 0.05) with monensin (32.1%) than other treatments (averaged 30.1%). Consequently, acetate to propionate ratio (A:P) of ROD (1.52) and RODE (1.56) was higher than monensin (1.32; P < 0.01) and control (1.44; P < 0.08). Differences in variables measured between ROD and RODE were minimal. These results indicated that the decreased DMD along with increased A:P with addition of ROD or RODE suggests that both ROD and RODE may be beneficial to HG fed cattle for reducing risk of rumen acidosis without negatively impacting fibre digestion.
PSXVI-25 25-hydroxy-vitamin-D3 improves productive performance of grazing Nellore cattle during dry season
Authors: Niehues Maria , Perdigão Alexandre , Vasconcellos Guilherme S , Correa Hugo L , Gouvea Daniel , de Carvalho Victor Valério , Acedo Tiago S
Published: October 2021

The aim with this trial was to evaluate three nutritional plans with the addition of 25-hydroxy-vitamin-D3 (HyD®) on performance of grazing Nellore steers in dry season. One hundred and twenty Nellore calves (iBW ± 267 kg; age, 9 mo) were randomly allocated to six paddocks (n = 20/paddock), in the following nutritional plans: mineral-proteic supplementation (PS; Fosbovi® Proteico 35; at 0.1% BW); PS with sodium monensin (PSM; Fosbovi® Proteico 35 M; at 0.1% BW); and mineral-protein-energetic supplementation (PES; Fosbovi® Proteico-Energético 25; at 0.3% BW); all three fed with or without addition of 1 mg/animal/d of 25-hydroxy-vitamin-D3 (HyD®), totaling six treatments. Both HyD® and supplements were provided by DSM Nutritional Products Brasil S.A. The intake and animal weight were collected daily and individually using an automatic feeder/scale system located in each paddock. Data were analyzed using the mixed procedure of SAS and means were compared by orthogonal contrasts (P < 0.05). Animals fed PSE, when compared to PSM and PS, presented higher ADG (PSE = 0.290 vs. PSM= 0.130 and PS = 0.030 kg/day; P < 0.01), FBW (PSE = 302.5 vs. PSM = 282.6 and PS = 271.7 kg; P < 0.01) and supplement intake (PSE = 1.640 vs. PSM = 0.190 and PS = 0.210 kg/day; P < 0.01). Additionally, regardless of nutritional strategy, HyD® supplementation increased ADG in 32 g/day (0.165 vs. 0.133 kg/day; P = 0.05) and FBW in 3.9 kg (287.5 vs. 283.6 kg; P = 0.05), compared to not-supplemented calves. No effects on supplement intake (either expressed in kg/day or %BW) were observed for HyD®. We conclude that 1 mg of HyD® can optimize performance of protein and protein-energetic supplemented cattle raised in tropical conditions during dry period.
Repeatability of gaseous measurements across consecutive days in sheep using Portable accumulation chambers
Authors: O’ Connor E , McGovern F M , Byrne D T , Boland T M , Dunne E , McHugh N
Published: October 2021

Portable accumulation chambers (PAC) enable gaseous emissions from small ruminants to be measured over a 50 min period, to date however, the repeatability of consecutive days of measurement in the PAC has not been investigated. The objectives of this study were to investigate: 1) the repeatability of consecutive days of gaseous measurements in the PAC, 2) the number of days required to achieve precise gaseous measurements, and 3) to develop a prediction equation for gaseous emissions in sheep. A total of 48 ewe lambs (c. 10 to 11 mo of age) were randomly divided into four measurement groups each day, for 17 consecutive days. Gaseous measurements were conducted between 0800 h and 1200 h daily. Animals were removed from perennial ryegrass silage for at least 1 h before measurements in the PAC and animals were assigned randomly to each of the 12 chambers. Methane (CH4; ppm) concentration, oxygen (O2; percentage) and carbon dioxide (CO2; percentage) were measured at 3 time points (0, 25, and 50 min after entry of the first animal into the first chamber). To quantify the effect of animal and day variation on gaseous emissions, between-animal, between-day and error variances were calculated for each gaseous measurement using a linear mixed model. The number of days required to gain a certain precision (defined as the 95% confidence interval (CI) range) for each gaseous measurement was also calculated. For all 3 gases the between-day variance (39% to 40%) accounted for a larger proportion of total variance compared to between-animal variance, while the repeatability of 17 consecutive days of measurement was 0.36, 0.31 and 0.23 for CH4, CO2 and O2, respectively. Correlations between consecutive days of measurement were strong for all 3 gases; the strongest correlation between d 1 and the remaining days for CH4, CO2 and O2 was 0.71 (d 1 and d 6), 0.77 (d 1 and d 2) and 0.83 (d 1 and d 5), respectively. A high level of precision was achieved when gaseous measurements from PAC were taken over 3 consecutive days. The prediction equation over-estimated gaseous production for all 3 gases: the correlations between actual and predicted gaseous output ranged from 0.67 to 0.71, with the r 2 ranging from 0.45 to 0.71. Results from this study will aid the refinement of the protocol for the measurement of gaseous emissions in sheep using the PAC.
Hemofiltration in the Management of Severe Pediatric Burns: Experience in a UK Burns Centre and Systematic Review
Authors: Rice Michael , Ibrahim Ibrahim , Aly Mohamed Ismail
Published: October 2021

Pediatric burns are life-threatening injuries due to the acute injury and secondary complications. In acute-phase burns, hypovolemia and vasoconstriction cause renal impairment. Sepsis and multiorgan failure compound the problem resulting in morbidity and mortality. This paper outlines 5 years’ experience using hemofiltration in major pediatric burns, and a review of the current literature. Retrospective patient data collection was undertaken identifying relevant pediatric burns undergoing Continuous Veno-Venous Hemofiltration. Data were analyzed to identify demographics, indication, duration of therapy, and outcomes. A systematic review was also performed using PRISMA principles. PubMed, Science Direct, and OVID databases were explored and relevant papers were included. From January 2015 to December 2019, hemofiltration was utilized in five cases. Age range 3 to 15 years (mean: 12), four males/one female, and mean weight 56 kg (12–125 kg). TBSA 21% to 61% (mean: 37.6%), mechanism of injury was scald—60%, flame—40%. Overall survival was 100%. Three patients were filtered for a brief period during the first 24 hours to correct metabolic acidosis and control temperature. Two patients required prolonged therapy. All patients recovered without further long-term renal support. A total of 3814 papers were identified for systematic review. Three were considered relevant for inclusion. This paper reflects the benefits of hemofiltration in the management of severe pediatric burns. Renal replacement therapy is useful in managing metabolic acidosis, temperature control, and renal failure. The current literature supports judicious use on a patient-by-patient basis. Given the lack of evidence in the literature, further studies are required to establish guidelines for the use of hemofiltration in pediatric burns.
Fibrocystic Changes of the Breast: Radiologic–Pathologic Correlation of MRI
Authors: Choe Angela I , Kasales Claudia , Mack Julie , Al-Nuaimi Mayyadah , Karamchandani Dipti M
Published: October 2021

Breast MRI provides high sensitivity but modest positive predictive value for identifying breast cancers, with approximately 75% of MRI-guided biopsies returning benign pathologies. Fibrocystic change (FCC) is a descriptive term used colloquially by many radiologists (and falling out of favor with many pathologists) to refer to several benign entities encountered in the breast. Many of the benign entities believed to comprise FCC can show enhancement on MRI. Recognizing the pathologic correlates of these enhancing lesions should help guide management after such a result on MRI-guided biopsy. Premenopausal women may present with clinical symptoms attributed to FCC, including pain, nipple discharge, breast lumps, or discrete masses. Benign entities associated with FCC include proliferative lesions such as usual ductal hyperplasia and sclerosing adenosis, and nonproliferative lesions including cysts, apocrine metaplasia, and stromal fibrosis. Fibrocystic change can be diffuse or focal. Diffuse FCC usually presents as non-mass enhancement (NME), often with persistent kinetics. Focal FCC can present as an irregular mass or focus with variable enhancement patterns including washout kinetics. Following a benign concordant MRI-guided biopsy result of one or more of the above entities, follow-up with MRI in 12 months is reasonable. Accurate radiologic–pathologic correlation can be achieved when careful review of histologic findings is carried out in the context of MRI features.