bluuebunny/crossref_metadata_2025_split huggingface dataset:
PSIX-19 Effect of protein and starch level on N balance and ruminal fermentation parameters in steers consuming low-quality forage: Bos taurus taurus
Authors: Cox Jodi R , Wickersham Tryon A 
Published: September 2024

Abstract
Globally cattle convert low-quality forage to beef and milk; therefore, understanding protein utilization in Bos taurus taurus is critical to enhancing sustainability as over and under-supplementation of protein are economically and environmentally costly. Low-quality forage lacks the N necessary for proper utilization and metabolic function. Supplemental protein improves low-quality forage utilization and is expected to increase N absorption and retention. Supplement starch can increase volatile fatty acid (VFA) production and energy supplied to the animal; however, too much starch decreases ruminally available N and pH potentially decreasing fibrolytic activity. Accordingly, our objective was to determine the effect starch supplementation on N balance and ruminal fermentation parameters in Bos taurus steers. Ruminally cannulated Angus steers [n = 5; body weight (BW) = 375 ± 45 kg] were used in a 4 × 4 Latin square to evaluate the effect of decreasing supplemental starch when consuming King Ranch Bluestem hay (3.5% CP, 73% NDF). Steers received four isonitrogenous (130 mg N/kg BW) supplements providing increasing levels of starch (2% starch = 100% soybean meal; 20% starch = 26.3% corn, 73% soybean meal, 0.7% urea; 38% starch = 51.6% corn, 47% soybean meal, 1.4% urea; 56% starch = 78.6% corn, 19% soybean meal, 2.4% urea). Five 14-d periods were conducted, consisting of 9 d adaptation and 4 d to measure intake and digestion, and 1 d for ruminal fermentation. Supplemental N intake decreased linearly (P &lt; 0.01) with increasing starch as the crude protein content of the soybean was underestimated. Forage and total N intake were not affected by starch level (P ≥ 0.17). Fecal and total urinary N excretion were not different between starch levels (P ≥ 0.43). Urinary ammonia-N and urea-N averaged 6.6 and 16.8% of total urinary N excretion, respectively, but no differences between starch levels were observed (P ≥ 0.39). Level of starch supplementation had no effect on N retention and absorption (P ≥ 0.50). There was a treatment × time interaction observed for ruminal ammonia concentration (P &lt; 0.01). All treatments, except 2% starch, peaked at 4 h post feeding, 20 and 38% treatments gradually decreased following four, but the concentration of ruminal ammonia decreased by 80% between 4 h and 8 h after feeding in the 56% starch treatment. Starch level had no effect total VFA concentration, VFA molar proportions, or ruminal pH (P ≥ 0.10). In conclusion, providing supplemental starch did not affect N balance or VFA production when fed to steers consuming low-quality forage. Nitrogen balance and VFA production likely were not affected because all supplements provided sufficient ruminally available N and, therefore, exerted minimal effects on forage utilization.
PSIX-20 Effect of protein and starch level on N balance and ruminal fermentation parameters in steers consuming low-quality forage: Bos taurus indicus
Authors: Cox Jodi R , Wickersham Tryon A 
Published: September 2024

Abstract
Despite the global importance of Bos taurus indicus production systems for converting low-quality forage to high-quality human consumable products, their responses to supplementation are not well characterized. Low-quality forage lacks the N necessary to support microbial activity and even correcting this deficiency may still fail to provide sufficient energy to meet animal requirements. Therefore, addition of starch may be warranted to increase animal performance and volatile fatty acid (VFA) production. Accordingly, our objective was to determine the effect starch supplementation on N balance and ruminal fermentation parameters in Bos taurus indicus steers. Accordingly, ruminally cannulated Brahman steers [n = 5; body weight (BW) = 420 ± 55 kg] were used in a 4 × 4 Latin square to evaluate the effect of increasing supplemental starch when consuming King Ranch Bluestem hay (3.5% CP, 73% NDF). Four supplements were formulated to be isonitrogenous (130 mg N/kg BW) and provide similar amounts of ruminally degradable protein while supplying increasing levels of starch (2% starch = 100% soybean meal; 20% starch = 26.3% corn, 73% soybean meal, 0.7% urea; 38% starch = 51.6% corn, 47% soybean meal, 1.4% urea; 56% starch = 78.6% corn, 19% soybean meal, 2.4% urea). Five 14-d periods were conducted, consisting of 9 d adaptation and 4 d to measure intake and digestion, and 1 d for ruminal fermentation. Supplemental N intake decreased linearly (P = 0.02) with increasing starch as the crude protein content of the soybean was underestimated. Forage and total N intake were not affected by starch level (P ≥ 0.27). Fecal and total urinary N excretion were not different between starch levels (P ≥ 0.20). Urinary ammonia-N decreased quadratically (P = 0.03) as a percentage of total N excretion, 9.5, 5.4, 5.8, and 6.9%, for 2, 20, 38, and 56% starch, respectively. In contrast, there were no significant effects of treatment (P ≥ 0.30) on urinary urea excretion. Level of starch had no effect on N retention and absorption (P ≥ 0.14). A treatment × time interaction was observed for ruminal ammonia (P &lt; 0.01) with concentrations peaking at h 4. The greatest ruminal ammonia was observed at h 4 for 56% starch it decreased markedly between h 4 and 8 and remained low thereafter. There was a small quadratic (P = 0.04) decrease in molar proportion of acetate. No other significant effects on VFA molar proportions, total VFA concentration, or ruminal pH were observed (P ≥ 0.12). In conclusion, providing increasing levels of supplemental starch to Bos taurus indicus steers consuming low-quality forage did not significantly affect N balance or VFA concentrations.
PSV-29 In vitro digestibility and in situ degradability of lobster and mixed crab shell waste material
Authors: Stahl Tess , Valentine Lydia , Abend Alan , Islam Tamanna , Erickson Peter 
Published: September 2024

Abstract
The objective of this research was to determine the in situ and in vitro degradability of lobster shell waste meal (LM) and crab shell waste meal (CM). Lobster and crab harvest are major industries within the New England states and the Maritime provinces. Harvest of the American lobster amounts to 54,643 tons caught and processed in 2020 in the New England states. The Atlantic Red Crab annual quota is around 1,814 tons. The Jonah Crab amounts to 5,725 tons. Due to the significant harvest, there is a resulting increase in byproducts and wastes at processing facilities providing potential feedstuffs for cattle. For both experiments, LM and CM were compared with soybean (SBM) and blood meals (BM). In experiment 1, 0.5 g of each meal were added to an artificial rumen incubator (Daisy, Ankom technologies) and DM degradability over 48 h was measured. In experiment 2, ruminally-cannulated Holstein cows (n = 4) in a 4 × 4 Latin square, had 5 g of sample were placed in Dacron bags in the dorsal rumen. Bags were in duplicate and removed at 2, 4, 8,12, 24, and 48 h time points. Eight bags were removed at 12 h for use in the in vitro intestinal degradability measurement using the modified three-step technique. Contrasts were: SBM vs. BM+LM+CM (SBM vs others), BM vs. LM+CM, and LM vs. CM. In experiment 2, 0 h bags served as a determination of fraction A, while the 48 h bags served as fraction C. Fraction B = 100% - (fraction A + fraction C). Degradation rate (kd) was calculated by converting % CP degraded from 2 to 24 h to Ln and then calculating the slope. In experiment 1, DM degradation was 45.8, 43.8, 76.4 and 100.1 % for SBM, BM, LM, and CM respectively; SBM vs others (P &lt; 0.01), BM vs. LM + CM (P &lt; 0.01), and no difference between LM vs. CM. Fraction A (CP) was 9.9, 8.1, 4.2, and 4.8% respectively; with SBM vs. others (P &lt; 0.03), BM vs. LM+CM (P &lt; 0.01), and no difference between LM vs CM. Fraction B (CP) was 76.2, 62.2, 28.9, and 42.6% respectively; with SBM vs. others (P &lt; 0.01), BM vs. LM + CM (P &lt; 0.01), and LM vs. CM (P &lt; 0.10). Fraction C (CP) was 4.41, 30.8, 46.8, and 37.5% respectively; with SBM vs. others (P &lt; 0.01), BM vs. LM + CM (P &lt; 0.03), and LM vs. CM (P &lt; 0.08). Intestinal CP digestibility was 56.2, 64.7, -5.83, and 10.5% respectively, with SBM vs others (P &lt; 0.01), BM vs LM+CM (P &lt; 0.01), and no difference between LM and CM. Results of these studies indicated that LM and CM may have some benefits in cattle diets, but feeding studies should be conducted.
PSV-28 Liver abscess microbiota of beef cattle administered in-feed tylosin differ according to abscess size and fraction
Authors: Gruninger Robert J , O’Hara Eóin , Zaheer Rahat , Andrés-Lasheras Sara , McAllister Tim A 
Published: September 2024

Abstract
Liver abscesses (LA) pose a significant challenge to the Canadian beef industry as they are estimated to cost the industry ~ $61.2 million annually. This is likely an underestimate as it does not account for losses in animal productivity. Tylosin phosphate is widely used to reduce LA, but concerns over antimicrobial use selecting for antimicrobial resistance has created an urgency to explore alternative approaches. Understanding the impact of tylosin on the microbial ecology of LA is crucial to this. We hypothesized that altering the duration of in-feed administration of tylosin to feedlot cattle would alter the microbial community of LA. To investigate this, we collected abscessed livers from cattle fed a diet containing tylosin 1) throughout finishing, 2) during the first 78% of the feeding or 3) during the last 75% of the feeding period. We examined LA microbial ecology of purulent material, abscess capsule tissue, originating from abscesses of different sizes using a metataxonomic approach. Our findings revealed that shortening tylosin administration did not notably alter the alpha (P &gt; 0.05) or beta-diversity (P &gt; 0.05) of LA microbial communities. There was a significant difference in microbial richness associated with abscess capsule (P &lt; 0.05) compared with bulk purulent material. Fusobacterium or Bacteroides ASVs dominated LA microbiomes, alongside probable opportunistic gut pathogens and other bacteria. Interestingly, classifying samples based on whether they originated from a liver with a single abscess, multiple abscesses or a very large abscess tended to differ in microbiome composition (P = 0.06). These insights contribute to our understanding of factors impacting liver abscess microbial ecology and will be valuable in identifying antibiotic alternatives. They underscore the importance of exploring varied approaches to address liver abscesses while reducing reliance on in-feed antibiotics.
PSVII-26 The effect of consuming red clover pasture and beneficial fatty acid supplements on ram lamb seminiferous tubule microscopic features
Authors: Morgan Staci-Ann , Barrett David , Papadopoulos Yousef , duynisveld John , Fredeen Alan , Glover Kathleen , Bidarimath Mallikarjun , Wort Jonathan 
Published: September 2024

Abstract
Fatty acids and phytoestrogens have been linked to short- and long-term alterations of reproductive performance in sheep. Red clover (RC) contains phytoestrogens, which have been linked to reduced reproductive performance in sheep. However, rams fed RC have increased omega-3 polyunsaturated fatty acids (n-3 PUFAs) and conjugated linoleic acid (CLA). These beneficial fatty acids may improve reproductive performance in rams. Fish oils (FO) contain significant amounts of n-3 PUFA and these improve reproductive performance. This study aimed to determine the effects of RC pasture and beneficial fatty acid supplementation on ram lamb seminiferous tubule histology. Crossbred ram lambs (n =32; 2 to 3 mo of age) were randomly divided into four groups (n = 8 per group) and balanced by body weight (BW) and dam parity. Two groups grazed tall fescue (TF)/RC, and two grazed TF pasture for 10 wk. These groups were then further randomly subdivided to receive a fat supplement [soybean oil (SBO; n = 8), SBO + CLA (n = 8), or FO (n = 8)] or no fat supplementation (CON; n = 8) during a 5-wk finishing diet. Then rams were slaughtered, and their testes were collected, fixed, and processed for histology. Testes cross sections were viewed under light microscopy and photos were taken for image analysis. Seminiferous tubule diameter, luminal diameter, cell count, and the average cell nuclear area: tubule area were determined using Image-Pro 10 software (Media Cybernetics). No significant differences were noted in tubular diameter or luminal diameter between any treatment groups. Those on TF had significantly greater cell counts (371.3 ± 39.6 vs. 305.9 ± 44.2; P &lt; 0.05) than rams on TF/RC pasture. Soybean oil produced a significantly lower ratio than SBO + CLA (0.000324 ± 0.000190 vs. 0.000408 ± 0.000300, P &lt; 0.05) but a greater cell count (498.2 ± 36.2) than CON, SBO + CLA, or FO (289.7 ± 52.9 vs. 282.2 ± 50.3 vs. 284.3 ± 50.9; P &lt; 0.001). No statistical difference was noted in ratios between the two pastures. Rams on TF/RC, with no supplementation had the least cell counts (227.2 ± 58.2) of all treatment groups, with significantly fewer counts than TF/RC + SBO rams (412.4 ± 62.0 P &lt; 0.05) and TF + SBO rams (583.9 ± 37.3; P &lt; 0.001); the latter had the greatest cell count of all treatment groups. Results suggest that RC and oil supplementation impact cell count, and oil supplementation impacts ratios but neither factor had an impact on tubule or luminal diameter.
PSX-15 Effect of starch supplementation on rumen bacterial abundance in Bos taurus indicus steers consuming low-quality forage
Authors: Fontenot Alyson B , McCann Joshua C , Cox Jodi R , Linder Haley F , Wickersham Tryon A 
Published: September 2024

Abstract
Deficient ruminally available nitrogen caused by a basal diet of low-quality forage can limit microbial growth in the rumen and decrease forage utilization. Protein supplementation is well-documented to improve forage digestibility and performance. Additionally, starch has been evaluated to increase energy supply to grazing cattle when the forage cannot support adequate levels of production. However, most research in this area has been conducted in Bos taurus taurus, especially the response of the rumen microbiome to supplementation. Accordingly, the objective of this study was to evaluate the effects of increasing starch supplementation on rumen bacterial populations in Bos taurus indicus steers supplemented protein and consuming low-quality forage. Ruminal samples were collected from five ruminally-cannulated Brahman steers (BW 420 ± 55 kg) used in a 4×4 Latin square fed a basal diet of King Ranch Bluestem Hay (3.5% CP and 73% NDF) provided ad libitum, and one of four isonitrogenous (130 mg N/kg BW) supplements with increasing levels of starch (2% starch= 100% soybean meal; 20% starch= 73% soybean meal, 26.2% corn, 0.8% urea; 38% starch = 47% soybean meal, 51.6% corn, 1.4% urea; 56% starch= 19% soybean meal, 78.6% corn, 2.4% urea). Rumen content samples were collected via rumen cannula at 4h post-feeding. Microbial DNA was extracted; full length 16S rRNA amplicon libraries were prepared using Kinnex kits and then sequenced on the PacBio Revio platform. Reads were analyzed using DADA2 and QIIME2. Statistical analysis was performed with the GLIMMIX procedure of SAS 9.4 (SAS Inst. Inc., Cary, NC). Firmicutes, Bacteroidata, Actinobacteriota, Verrucomicrobiota, and Euryarchaeota were the most abundant phyla in all treatments (83, 10, 3, 0.4, and 1%, respectively), and were not affected by treatment (P ≥ 0.10). Christensenellaceae R-7 group, Rikenellaceae RC9 gut group, Lachnospiraceae-XPB1014-group, Butyrvibrio, Lachnospiraceae-NK3A20-group, and Prevotella represented the most abundant genera for all treatments (7, 5, 11, 9, 7, and 3%, respectively). Lachnospiraceae-XPB1014-group and Lachnospiraceae-NK3A20-group responded quadratically (P ≤ 0.02) to increasing starch with decreased abundance for the 20% and 38% starch supplement. Comparatively, relative abundance of Butyrvibrio responded quadratically (P &lt; 0.01) with increased abundance in the 20% and 38% starch supplement. Pseudobutyrvibrio increased with supplementation of 20% starch and then decreased as starch supplementation increased (quadratic, P = 0.04). In conclusion, supplementation of starch elicited changes in microbial relative abundance at the genus level with the response in Butyrivibrio suggesting greater fibrolytic activity. Forage and total digestible NDF intake in these steers decreased with increased starch supplementation; however, TDOMI was not affected by starch provision.
PSX-16 The effect of short-term heat stress on physiological, hematological, and immunological parameters of Florida Cracker Sheep
Authors: Mills-Widemon Anijia , Harrison Makenzie , Ikuejamoye-Omotore Sola , Reyes Zaira M Estrada , Terrill Thomas H , Cervantes Andres Pech 
Published: September 2024

Abstract
Florida Cracker sheep are a heritage sheep breed that was developed under natural selection in Florida, US. The objective of this study was to evaluate the effect of short-term heat stress on rectal temperature, respiration rate, hematological parameters, and IgA concentrations of Florida Cracker ewes (2 yr of age). A total of fourteen ewes were allocated to heat stress (HT, n = 7) or cooling (CTL, n = 7) conditions for 6 wk during the summer season. Treatment groups were grouped in covered concrete floor pens with similar dimensions and characteristics and had access to shelter, feed, and freshwater ad libitum. The HT pen was exposed to regular ambient temperatures, and for the cooling pen, an evaporative cooling fan was used. Data for ambient temperature and relative humidity of HT and CTL pens were recorded every week to estimate the temperature humidity index (THI). Blood samples were collected from each experimental ewe 1 wk before the start of the experiment (baseline) and at wk 1, wk 2, wk 3, wk 4, wk 5, and wk 6 post-treatment. Blood samples were analyzed using a hematology analyzer (Vetscan HM5, Zoetis). Plasma was extracted from the blood and was used to evaluate IgA concentrations with a commercial kit. For the statistical analysis of the physiological, hematological, and immunological parameters, a mixed model with repeated measures was used. Fixed effects included treatment (HT or CTL), wk (1 to 6), and the treatment by week interaction. Animal was fitted as a random effect and the baseline data was used as a covariate. The THI for the HT and CTL groups ranged from 81.3 to 89.5 and from 73.5 to 75.6, respectively. The HT group presented a significant (P &lt; 0.05) increase in respiratory rate when compared with the CTL group. No significant changes were observed for rectal temperature and IgA concentrations in the experimental groups. However, for wk 3, a significant (P &lt; 0.05) increase of neutrophils and a decrease in lymphocyte % was observed for the HT group. In conclusion, short-term heat stress increased respiratory rate and neutrophil % and decreased the lymphocyte % in Florida Cracker ewes. It is possible that heat stress could have a detrimental impact on immune mechanisms in Florida Cracker ewes. Further studies are required to investigate the effects of long-term heat stress.
PSX-19 Variation in nutritive value of whole cottonseed from the Regional Breeding Testing Network
Authors: Rigney Diva N , Rockwell Macy , Underwood Anna Grace G , Koebernick Jenny , Mullenix Kimberly , Smith W Brandon 
Published: September 2024

Abstract
Whole cottonseed serves as a readily accessible, nutritional, and cost-effective supplementary feed for beef cattle. Standard estimates indicate that whole cottonseed contains approximately 52% neutral detergent fiber (NDF), 24% crude protein (CP), and 18% crude fat. For more than 15 yr, the Regional Breeders Testing Network (RBTN) has conducted a multi-environment trial (MET) for breeders to evaluate germplasm to include whole cottonseed. The trial presents opportunities to analyze variations among cultivars concerning their nutritional value. Therefore, the purpose of this study was to assess the variability in nutritive value of whole cottonseed from the 2023 RBTN MET. Samples from 20 RBTN cotton varieties were obtained and assayed for NDF, ADF, ADL, and CP. Samples were also subjected for batch culture in vitro true digestibility (IVTD) and crude fat. In our study, NDF (total cell wall content) was less than previously reported book values (45.8% vs. 51.6%). Crude protein was consistent with book values (25.0% vs. 24.4%) and had the least degree of variability among the nutrients tested. However, crude fat (the primary energy source in whole cottonseed) in our samples was greater than values previously reported (20.2% vs. 17.5%) and had a greater degree of variability. Our findings indicate that the nutritional value of whole cottonseed may differ depending on the variety acquired. This research lays the groundwork for pinpointing the genetic factors responsible for regulating its nutritional value.
PSX-20 The inclusion of a tannin-based product evaluated in a typical feedlot diet under tropical conditions increases the molar proportion of propionate in a dual-flow continuous-culture system
Authors: Paula Eduardo , Dourado Stephanie , Magnani Elaine , Amancio Bruna , Loregian Kalista , Silva Thiago , Silva Melaine , Manella Marcelo Q , Arnandes Renata Branco 
Published: September 2024

Abstract
The objective of the present study was to evaluate increasing levels of a tannin-based product and a monensin (positive control; unique dose) using a dual-flow continuous-culture system. Diets were randomly assigned to ten fermenters in a replicated 5 x 5 Latin square with three, 10-d experimental periods consisting of 7 d for adaptation and 3 d for sample collection. Four different levels were tested independently, resulting in 5 treatments: tannin at levels of 0 (negative control), 0.07, 0.14, and 0.21 (% of DM of the total diet) and monensin as positive control at 28 mg/kg DM. The tannin-based product was a specific blend of tannin and saponins, composed of quebracho and chestnut tannin extracts, SilvaFeed-BX). Diets were prepared as concentrate mixes that were combined with sugarcane bagasse, corn grain, dry distillers grain, citrus pulp, peanut meal, and urea. Liquid and solid flow rates were adjusted to 10 and 5.0%/h, respectively. Samples were collected for digestibility, ruminal fermentation, and microbial growth. The basal diet consisted of a typical finishing diet for beef cattle (16:84 roughage:concentrate ratio). All results were assessed for residual normality and variance homogeneity. All variables were fitted through generalized mixed models (GLIMMIX procedure) and compared by using Tukey test (multiple comparison) and polynomial regressions (tannin concentrations, which were analyzed for linear and quadratic responses. Partial data were presented in the table below. Total VFA concentration, molar proportion of butyrate, and total Branched-chain VFA were not affected by treatments (P &gt; 0.05). Molar proportion of acetate of the tannin-based product at 0.07 % of DM tended to be decreased compared with all other treatments. Molar proportion of propionate increased quadratically (P = 0.05) reaching the peak at the level of 0.07 % of DM, which were greater than monensin treatment. In conclusion, our results indicate that a smaller dose of a tannin-based product (0.07 g/kg of DM) might manipulate ruminal fermentation by increasing molar proportion of propionate in typical feedlot diet fed under tropical conditions. This is important from an energetic standpoint for the animal host, since propionate is the precursor of glucose synthesis in ruminants.