bluuebunny/crossref_metadata_2025 huggingface dataset:
346 Substitution of Modified Distillers Grains with Soybean Meal with Or Without Hulls Had Negligible Effect on Growth Performance, Efficiency and Carcass Traits in Yearling Steers
Authors: Ross Cassidy , Bird Scott , Smith Zachary K , Rusche Warren C
Published: November 2023

Changes to the fuel landscape in the United States have resulted in changes in long-held supplemental protein price relationships. The objective of this study was to evaluate substituting oilseed meal for corn processing co-products. Predominately Angus steers [initial shrunk body weight (BW) = 435 ± 23.6 kg] were used in a 118-d experiment using three treatments: modified distillers grains (MDGS)fed at 15% diet DM (MDGS) replaced by either soybean meal and corn (9 and 6% of DM, respectively; SBM), or soybean meal and soyhull pellets (9 and 6% of DM, respectively; SBM-SBH). Steers (n = 240) were individually weighed and allotted to one of 24 pens (n = 10 steers per pen; 8 pens per treatment) at the Southeast Research Farm located near Beresford, SD. Dietary concentrations of crude protein and neutral detergent fiber based on tabular values and weekly batching records were 12.3 and 17.6%, 12.8 and 14.5%, and 12.8 and 17.8% for MDGS, SBM, and SBM-SBH, respectively. Data were analyzed as a randomized complete block design using the GLIMMIX procedure of SAS 9.4 with treatment and block as fixed effects; pen was the experimental unit. Pen conditions were wet and muddy during the final weeks of this experiment; consequently, final BW was calculated by dividing hot carcass weight (HCW) by a common dressing percentage of 62.5. No differences amongst treatments (P ≥ 0.11) were found for carcass-adjusted final BW, dry matter intake (DMI), average daily gain (ADG), or feed efficiency. Dietary treatment had no effect (P ≥ 0.11) on HCW, dressing percentage, ribeye area, rib fat, marbling score, USDA Yield Grade, percent empty body fat (EBF), or final BW adjusted to 28% EBF. Distribution of USDA Quality and Yield grades were unaffected by treatment (P ≥ 0.39). Dietary treatment did not affect liver abscess incidence and severity (P = 11). Net energy values calculated from animal performance agreed closely with tabular estimates with observed to expected ratios for net energy equaling one. In this experiment, feeding supplemental protein sources with enhanced diet conditioning attributes and greater concentrations of ruminally undegradable protein provided no advantage to cattle performance. These results indicate that protein source decisions can be based upon price per unit of delivered crude protein.
364 The Effects of Replacing Dried Distillers Grains with Solubles with a Heat-Treated Soybean Meal in Forage-Based Growing Cattle Diets
Authors: Gullickson Grady J , Nichols Madeliene , Entzie Yssi L , Hansen Lydia E , Underdahl Sarah R , Tobin Colin T , Swanson Kendall C , Carlson Zachary E
Published: November 2023

This study aimed to evaluate the effects of increased concentrations of metabolizable protein and lysine from heat-treated soybean meal (TSBM) in forage-based growing cattle diets predicted to have positive metabolizable protein balance. Seventy Angus-based steers (298 ± 16 kg initial BW) were utilized in an 85-d randomized generalized block design with animal as the experimental unit. Dietary treatments were arranged to replace a proportion of the basal protein source, DDGS included at 16% dietary dry matter (DM), with TSBM at rates of 0% (TSBM0), 4% (TSBM4), 8% (TSBM8), and 12% (TSBM12) dietary DM. Steers were provided with ad libitum access to feed and water in a monoslope barn with dry-lot access. The basal diets contained (DM basis) 44% corn silage, 37% oat hay, and 3% supplement. Steers were blocked by BW into light, medium, and heavy blocks. Daily feed disappearance was measured using an automated feed system (Insentec Roughage Intake Control, Hokofarm B.V., Marknesse, The Netherlands), with disappearance assumed to be intake. Steers were individually weighed every 28 d to calculate average daily gain (ADG) throughout the experiment. Growth performance and feed intake were analyzed utilizing the MIXED procedure of SAS with fixed effects of body weight block and TSBM inclusion level. Treatments were evaluated when the F test was significant (P ≤ 0.05). There were no differences (P ≥ 0.16) for ending BW, ADG, dry matter intake (DMI), or gain:feed (G:F) among treatments (Table 1). Therefore, in growing diets predicted to be sufficient in metabolizable protein, replacing distillers grains with a source of metabolizable protein and amino acids provided by heat-treated soybean meal did not affect growth performance.
366 Effects of Acidosis Bout Events on Animal Growth and Development, and the Effectiveness of Liver Abscess-Controlling Antibiotic on Diminishing Its Incidence
Authors: Batista Luiz Fernando Dias , Rivera Madeline E , Tedeschi Luis O
Published: November 2023

Ruminal acidosis is a common metabolic disorder that affects feedlot and dairy cattle and occurs when the supply of organic acids from fermentation exceeds its absorption, accumulating acid content in the rumen. Virginiamycin (VM) has inhibitory effects on primary liver abscess-causing bacteria. In feedlot animals, dietary VM has been shown to reduce rumen acidosis and improve feed conversion actively. This study evaluated ruminal pH over 150 days on feed (DOF) of growing and finishing beef cattle and investigated the relationships between ruminal pH and growth and development outcomes and the effectiveness of the continuous or intermittent provision of VM in 120 Angus-crossbred steers. Steers received VM (240 mg/d) as follows: no VM (T000); VM in the last 50 d (T001); VM for the last 100 d (T011); VM in the first 50 d (T100); VM in the first 100 d (T110); and VM for 150 d (T111). Animals were fed a grower-type diet (metabolizable energy [ME]: 2.45 Mcal/kg; crude protein [CP]: 12.2 % dry matter basis [DM]) for 50 d before the adaptation of a finisher-type diet (ME: 2.60 Mcal/kg; CP: 10.6% DM) over a 17-d period. The finisher-type diet was fed for the remaining 84 days. On d -1 and d 82 each animal received an indwelling pH bolus to record ruminal pH at 10-min intervals. Acidosis bout event was categorized as if the pH stayed below 5.6 for 3 hours. Data were analyzed using a random coefficient statistical model, binary data was analyzed using the logit link function and correlations were analyzed using PROC CORR in SAS (Table 1). Duration under pH 5.8 and 5.6 tended to have a negative correlation with gain to feed (G/F; P ≤ 0.080), and % of the time that pH remained below 5.6 when under 5.8 was negatively correlated with G/F (P = 0.007) and tended to have a negative correlation with average daily gain (ADG; P = 0.081). Similarly, acidosis bouts event and duration of bout event (DURB) tended (P ≤ 0.074) to have a negative correlation with G/F, while ADG was negatively correlated (P = 0.035). The number of acidosis bout events and probability of acidosis bout events to occur increase linearly (R2 = 0.89, P < 0.001, and R2 = 0.77; P < 0.001, respectively) as DOF progressed. The probability of an acidosis bout event decreased by 46% for the T111 treatment compared with T000 (35.43% vs. 18.82%; P = 0.049). Acidosis bout event seems to affect the growth and development of beef steers negatively, and it appears to be more critical as DOF progress. Administration of VM at 240 mg/d throughout the whole feeding period seems to reduce the incidence of acidosis bout events.
377 Evaluation of Feed Intake, Feed Efficiency and Days on Trial in Growing Goats Fed a Total Mixed Diets Using Growsafe Feeding Technology
Authors: Kidane Negusse F , Irvin Merrick E , Foxworth William B , Carstens Gordon E , Horner Scott , O'Reilly Keara
Published: November 2023

The objectives of this study were to evaluate the effects of breed and days on trial (DOT) on feed intake, growth rate, and feed efficiency of growing goats. Nineteen female goats (10 Alpine and 9 Spanish) with an initial BW of 38.8 ± 2.8 and 35.5 ±3.1 kg, respectively, were randomly assigned within breed to one of two pens (5 goats/pen), each equipped with GrowSafe feed bunks. A pelletized total mixed diet (TMD) was fed twice per day and goats had ad libitum access to feed and water throughout the 84-d trial. Daily feed intake (DMI) was collected with GrowSafe automated feeding system, and BW was measured biweekly. Linear regression of 14-d BW on DOT was used to derive ADG, mid-test metabolic BW (MBW) and expected DMI of individual goats at 42, 56, 70, and 84 DOT. Expected DMI was predicted by linear regression of DMI on MBW and ADG, with RFI calculated as a difference between actual and expected DMI for each DOT. Data were analyzed using a repeated-measures model with a fixed effect of breed, DOT as a repeated measure, and breed x DOT interaction with a pen as a random effect. The interaction was not significant for either of the response variables. Alpine goats had greater (P < 0.05) initial and final BW (37.6 kg and 51.7 kg, respectively) than Spanish goats (34.7 kg and 46.5 kg, respectively) although ADG (0.233 kg/d vs 0.191 kg/d) did not differ. DMI (P = 0.10) and RFI (P = 0.09) tended to be greater in Alpine than in Spanish goats (0.57 kg vs -0.64 kg). However, G:F was not affected (P > 0.70) by breed. As DOT increased from 42 to 84, MBW increased, while ADG, DMI, and G:F decreased. Further research is warranted to determine changes in phenotypic variances of ADG and DMI to determine the minimal DOT needed to accurately measure feed efficiency in growing goats. Our results suggest that Spanish goats tended to consume less feed and tended to be more efficient (negative RFI) than their counterpart Alpine goats. Further research is needed to compare the life-cycle efficiency of Alpine and Spanish goats.
374 Birth Season and Production System Effects on Post-Weaning Growth and Gastrointestinal Nematode Infection of Katahdin Lambs
Authors: Murphy Tom W , Hess Andrew , Miller Jim E , Burke Joan M
Published: November 2023

The objective was to estimate birth season (F = fall, W = winter) and production system (C = conventional, O = organic) effects on Katahdin lamb growth and gastrointestinal nematode (GIN) infection. Lambs were weighed and weaned at ~60 d of age and body weight (BW, n = 5,089), fecal egg count (FEC, n = 4,772), and packed cell volume (PCV, n = 4,962) were recorded at ~90, 120, and 150 d of age. Records were analyzed from 599, 142, 1,113, and 126 F-C, F-O, W-C, and W-O lambs, respectively. Lambs were not dewormed and FEC was transformed as: LFEC = log10(FEC + 25). Traits were analyzed as repeated measures with fixed effects of time, sex, birth/rear type, and season-system, the linear covariate of actual age at 90 d, and random effects of sire, birth year, and contemporary group. The time x season-system interaction was significant for all traits (P < 0.001; Figure 1). At 90 d, BW was greater for W-C and W-O than F-C and F-O (P ≤ 0.05). By 150 d, W-O lambs had greater BW (P ≤ 0.04) than all other season-systems which weren’t different from each other. Lamb LFEC was greatest for F-C (P < 0.001), intermediate for F-O, and least for W-C and W-O at 90 d. All season-systems had similar LFEC at 120 d, but W-C lambs had greater LFEC at 150 d than all others (P < 0.01). At 90 d, PCV was less for F-C than all others (P ≤ 0.02) except W-O. Both F-C and F-O had greater PCV (P < 0.001) than W-C and W-O at 120 d and, at 150 d, PCV was less for W-C than all others (P < 0.001). To investigate production impacts of GIN infection in different season-systems, average daily gain from weaning to 90 d (ADG60-90, n = 1,842) was analyzed in a similar model with the additional linear covariate of LFEC at 90 d (LFEC90). The season-system x LFEC90 interaction was significant (P < 0.01), indicating differing impacts of GIN infection. A one-unit increase in LFEC90 (e.g., ~500 vs. 5000 eggs/g) had negative impacts on ADG60-90 for W-O, F-C, and W-C (-27.1, -22.4, and -12.5 g/d, respectively) and solutions were not different from one another. However, LFEC90 did not affect F-O ADG60-90 potentially due to decreased performance (158.4 g/d) than other season-systems (171.5 – 204.3 g/d). Overall, BW was less for F than W lambs and FEC decreased with age for F with the opposite for W lambs. Slight advantages in performance were observed for W-O compared with W-C lambs. Season-system differences could be attributed to varied forage quality and breeding objectives and results utilized in precision sheep management. USDA is an equal opportunity provider and employer.
399 Methionine and Guanidinoacetic Acid Supplementation Throughout the Periconceptual Period of Gestation Alters Metabolite Concentrations and Fetal Development
Authors: Hauxwell Kathlyn , Cushman Robert A , Caton Joel S , Ward Alison , Lindholm-Perry Amanda , Snider Alexandria P , Freetly Harvey C , Dahlen Carl R , Amat Samat , Neville Bryan W , Thorson Jennifer , Oliver William T , Miles Jeremy R , Crouse Matthew S
Published: November 2023

Recent research reported changes in fetal growth due to increased methyl donor availability through periconceptual supplementation of the dam. We hypothesized that maternal supplementation of methionine (MET) or guanidinoacetic acid (GAA) during the periconceptual period will result in a methyl donor surplus or deficiency in maternal serum and ultimately influence fetal body and organ weight at d +63 gestation. The objectives of this study were to evaluate effects of methyl donor surplus or deficiency during the periconceptual period of gestation on metabolite concentrations in the heifer and the effects on early fetal development. Eighty MARC II heifers (n = 20 per treatment, initial BW = 346 ± 8 kg) were stratified by age and weight to one of four treatment groups to receive 100 g of supplement: ground corn carrier as control (CON), MET (10 g/d) in ground corn, GAA (40 g/d) in ground corn, and MET + GAA (10 g/d MET + 40 g/d GAA) in ground corn. Supplementation began 63 d before breeding (d –63) until d 63 of gestation (d +63), and serum samples were collected before feeding on d -63, at breeding, and d +63. Heifers were bred using male sexed semen from the same sire, and 35 heifers were confirmed pregnant (CON, n = 10; MET, n = 8; GAA, n = 7; MET + GAA, n =10) and harvested at d +63 of gestation to collect maternal and fetal samples. Data were analyzed as a 2 × 2 factorial design with 2 levels of MET and 2 levels of GAA. Methionine concentrations in maternal serum were greater (P = 0.05) in MET and MET + GAA supplemented heifers at d 0 and d +63 compared with CON and GAA at d -63, d 0, and d +63. There were no differences (P ≥ 0.15) in the concentration of GAA or creatine due to supplementation; however, both were decreased at breeding (P < 0.01) compared with d -63 and d +63. Fetuses from MET supplemented heifers had greater (P = 0.01) brain weight and Longissimus muscle than dams not receiving MET. We conclude that MET supplementation during the periconceptual period can alter methyl donor availability and increase fetal muscle development. USDA is an equal opportunity provider and employer.
PSXII-8 Effects of Pre-Synchronization with Short-Term Melengesterol Acetate in Nulliparous Beef Heifers
Authors: Nicholls Griffin T , Funnell Bethany J , Lemenager Ron , Stewart Kara R
Published: November 2023

Conception rates in nulliparous beef heifers can be greatly influenced by their ability to reach puberty at or prior to the initiation of a breeding season. Previous research has analyzed the efficacy of utilizing both long and short-term exposure to a source of progesterone via a controlled internal drug release insert (CIDR) prior to estrous synchronization with timed artificial insemination (TAI) and found improved conception rates. The purpose of this study was to evaluate the effects of feeding melengesterol acetate (MGA) immediately and 10 days before estrous synchronization. Ninety-three crossbred heifers (395.67 ± 5.37 kg) were blocked by BW, genetics, and reproductive tract scores and allotted to 3 treatments. The 3 treatment groups were: 7-day Co-synch + CIDR without presynchronization (CON, n = 31); 2cc PGF2α (Lutalyse) followed by melengesterol acetate feeding for 7 d before the start of the 7-day Co-synch + CIDR program (PRE, n = 31); and 2 mL Lutalyse followed by MGA feeding for 7 d followed 10 d later by the start of the 7-day Co-synch + CIDR program (PRE+10, n = 31). The 7-day Co-synch + CIDR protocol was initiated on d 0 by administering a 2 mL IM injection of GnRH and placing a CIDR into the vagina. The CIDRs were removed 7 days later and accompanied by 2 ml IM injection of PGF2α. An injection of GnRH occurred 60 to 66 hours following PGF2α at TAI with frozen semen from a single bull. Ten days after TAI, heifers were exposed to a bull. Estrotect patches were applied throughout the study to assess estrous behavior. Ovaries were visualized 24 hours post TAI to determine whether ovulation occurred. Pregnancy was determined on days 40, 64, and 109 post TAI via transrectal ultrasonography. Blood was collected via jugular venipuncture (d -19, MGA initiation and termination, d 0, d 7, and d 9) and serum progesterone determined. Performance data were analyzed using the MIXED procedure and conception data were analyzed using the GLIMMIX procedure of SAS. Heifers in the PRE+10 treatment group had higher levels of progesterone (P = 0.04) at d 0 than PRE heifers. At d7 there was a tendency (P = 0.07) for PRE+10 heifers to have greater concentrations of progesterone than PRE, but did not differ by d 9 (TAI, P = 0.36). TAI conception rates in heifers in the PRE treatment group (63%) tended (P = 0.09) to be greater compared with the controls (35%) and not different from PRE+10 (43%), with no differences in season-long pregnancy rates (P > 0.15). Presynchronization with MGA immediately before TAI synchronization can increase conception rates early in the breeding season in beef heifers.
PSIV-27 Effect of Different Ratios of Phytogenic Feed Additives in Weaned Pigs Challenged with a Pathogenic Escherichia Coli
Authors: Chang Seyeon , An Jaewoo , Song Dongcheol , Cho Hyunah , Park Sehyun , Jeon Kyeongho , Kim Hyuck , Cho Jinho
Published: November 2023

This study was conducted to investigate the effects of supplementing different ratios of phytogenic feed additive (PFA) to weaned pigs challenged with pathogenic Escherichia coli (E. coli) on growth performance, nutrient digestibility, intestinal barrier integrity, and immune response, and to determine the optimal mixing ratio for PWD prevention. A total of 48 four-week-old weaned pigs with initial body weight of 8.01 ± 0.39 kg were placed in individual metabolic cages, and then randomly assigned to eight treatment groups. The eight treatments were as follows: a basal diet without E. coli challenge (negative control, NC), a basal diet with E. coli challenge (positive control, PC), PC with supplementing 0.1% mixture of 20 % bitter citrus extract (BCE), 10% microencapsulated blend of thymol and carvacrol (MEO), and 70% excipient (T1), PC with supplementing 0.1% mixture of 10% MEO, 20% premixture of grape seed and grape marc extract, green tea, and hops (PGE), and 60% excipient (T2), PC with supplementing 0.1% mixture of 10% BCE, 10% MEO, 10% PGE, and 70% excipient (T3), PC with supplementing 0.1% mixture of 20% BCE, 20% MEO, and 60% excipient (T4), PC with supplementing 0.1 % mixture of 20% MEO, 20% PGE, and 60% excipient (T5), and PC with supplementing 0.1 % mixture of 10% BCE, 20% MEO, 10% PGE, and 60% excipient (T6; Table 1). The experiments were progressed in 16 days, including 5 days before and 11 days after the first E. coli challenge (d 0). In the E. coli challenge treatments, all pigs were orally inoculated by dividing a total of 10 mL of E. coli F 18 for 3 consecutive days from d 0 post-inoculation (PI). Compared with the PC group, the PFA2 and PFA6 groups significantly increased (P < 0.05) feed efficiency and decreased (P < 0.05; Table 2) diarrhea during the entire period (Table 3). At d 11 PI, the PFA6 group significantly improved (P < 0.05) gross energy digestibility compared with the PFA1 group (Table 4). The PFA6 group significantly decreased (P < 0.05) tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6) in serum (Table 5) and increased (P < 0.05) the villus height to crypt depth ratio (VH:CD; Table 6; Figure 1). The PFA2 significantly decreased (P < 0.05) the relative protein expression of calprotectin in the ileum (Table 7). In conclusion, improvements in growth performance, diarrhea reduction, and immunity enhancement are demonstrated when 10% BCE, 20% MEO, 10% PGE, and 60% excipient are mixed.
PSIV-29 Performance and Resiliency Against Gastrointestinal Parasites of Pregnant Does and Ewes Raised Indoor and Outdoor During the Winter Season
Authors: Lamsal Sadikshya , Karki Uma , Chaudhary Santoshi , Dhakal Durga
Published: November 2023

Small ruminants in the southeast USA are mostly raised on pastures (outdoor) irrespective of seasons and associated weather conditions. During the extreme weather conditions, such as that occur in winter, animals may perform better while kept indoors. However, literature is scant on the benefits of keeping animals indoors during winter. The objective of this study was to assess the performance and resiliency against gastrointestinal (GI) parasites of pregnant does and ewes raised indoor and outdoor in winter. The experiment was conducted for 45 days from late January to mid-March 2023. Sixteen pregnant Kiko does, and eighteen pregnant Katahdin-St. Croix cross ewes were divided into two uniform groups. Group-1 animals (8 does and 9 ewes) were kept outdoors in a grazing plot that consisted of mobile shelters, mineral feeders, hay feeders, and watering troughs. Group-2 animals (8 does and 9 ewes) were kept indoors in individual pens with consisting of containers for providing water, minerals, hay, and grain. Both groups were given ad libitum hay, minerals, and water as well as corn-soybean mixed in 3:2 ratio at the rate of 0.8% of animal live weight. Ambient temperature and relative humidity (RH) were measured for both systems. Animal performance data [body weight, body condition score (BCS), and FAMACHA score] and fecal samples were collected on Day 1, weekly during the study, and at the end of the study. Fecal samples were analyzed for the type and quantity of GI parasites using the McMaster technique, and parasite eggs per gram of animal feces (EPG) was calculated. Weather data and animal performance data were analyzed using the GLM procedure and EPG data using the Wilcoxon Rank-Sum test in SAS 9.4. Temperature was higher (13.3%, P < 0.01) while RH was lower (6.25%, P < 0.01) in the indoor system. Ewes showed greater BCS (4.86%, P < 0.01) and does showed better FAMACHA score (8.5%, P < 0.01) in indoor system compared with outdoor ewes and does, respectively. Haemonchus contortus was found to be the major GI parasite affecting animals kept in both systems. Indoor ewes showed greater EPG than outdoor ewes (89.8%, P < 0.05). Results suggest that indoor rearing of pregnant does and ewes during winter can enhance their performance. Further research is needed to determine the possible reasons for greater EPG in pregnant ewes raised indoor vs. outdoor.
PSI-14 Weaning Stress Increases Bile Cysteine and Cysteinylglycine Concentrations in Pigs
Authors: Outlaw Alex , Gachman Alexandra M , Bartosh Julia , Rudar Marko
Published: November 2023

Weaning is a critical time for pigs that is associated with nutritional, social, and environmental stressors that lead to reduced feed intake and poor nutrient utilization. Cysteine is a sulfur amino acid and a key constituent of glutathione (GSH), a major intracellular antioxidant and potential regulator of intestinal redox status. Glutathione is present in biliary secretions and may be an important source of cysteine to intestine in newly weaned pigs. The objective of this study was to determine amino thiol and amino acid concentrations in bile. Piglets (initial BW = 7,233 ± 683 g) were either weaned on day 21 of age (W; n = 9) and euthanized after 2 d or remained on the sow until day 23 of age (NW; n = 9) and were euthanized. Weaned pigs were fasted and allowed free access to water. After euthanasia, bile (directly from the gallbladder), jejunum, and ileum samples were collected. Bile amino acids and bile amino thiols were analyzed by reversed phase HPLC following precolumn derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate and 4-fluoro-7-aminosulfonylbenzofurazan, respectively. Reverse transcription quantitative real-time PCR was performed to measure cysteine transporter expression in jejunum and ileum. Cysteine concentration was greater in W than NW pigs (1,203 versus 324 ± 99 µmol/L; P < 0.0001). Both γ-glutamylcysteine (7.1 versus 2.2 ± 2.1 µmol/L), the direct precursor for GSH synthesis, and cysteinylglycine (203 versus 110 ± 30 µmol/L, the direct product of GSH degradation, were greater in W pigs than in NW pigs (P < 0.05). Bile GSH concentration tended to be greater in W than NW pigs (9.1 versus 5.3 ± 2.8 µmol/L; P = 0.07). Taurine, derived from cysteine oxidation, was greater in W than NW pigs (180 versus 91 ± 23 µmol/L; P < 0.05), whereas glutamate (11.4 versus 8.8 ± 1.9 µmol/L) and glycine (463 versus 403 ± 62 µmol/L), additional amino acid constituents of GSH, were not different between groups (P > 0.10). Expression of cysteine transporters SLC1A4, SLC1A5, SLC6A14, SLC6A19, SLC7A9, and SLC7A11 in jejunum and ileum were not different between groups (P > 0.10). Despite no feed intake after weaning, cysteine concentrations increase in bile. While this is likely due to bile accumulation in the gallbladder after weaning, high bile cysteine, cysteinylglycine, and glycine concentrations could potentially be a source of these amino acids for enterocytes during weaning stress.
PSV-12 The Influence of Trace Mineral Source on Rumen Trace Mineral Solubility and In-Vitro Fiber Digestion in Steers Fed a Lactating Dairy Diet
Authors: Loh Huey Yi , Mezzomo Rafael , Gomes Daiany I , Tangredi Briana V , Guimaraes Octavio , Gifford Ryan J , Miller Alexandra C , Levenson Jonah R , Thorndyke Meghan P , Spears Jerry W , Engle Terry E
Published: November 2023

Eight individually fed fistulated steers (410 ± 10 kg) were used to investigate the impact of trace mineral source on rumen trace mineral solubility and in vitro fermentation characteristics. Steers were sorted by body weight, into two trace mineral (TM) treatment groups (n = 4/treatment). Treatments consisted of TM supplementation at 10 mg Cu, 40 mg Mn, and 60 mg Zn/kg DM from either sulfate TM (STM) or hydroxy TM (HTM) sources. Steers were fed a diet balanced to meet the nutrient requirements (TMR) for lactation dairy cow. Dietary TM treatments were mixed with dried distillers grains and top dressed daily. Rumen contents were collected at 0, 2, and 4 h post feeding on d 1 and 14 of the experiment. Rumen samples were centrifuged at 1,500 × g for 15 min. The supernatant and the digesta pellet were frozen, separately, at −20°C for TM analysis. On d 15 of the experiment, approximately 500 g (wet weight) of rumen contents were collected from each steer 2 hours post-feeding. Strained ruminal fluid (SRF) was obtained by squeezing the rumen contents through 2 layers of cheese cloth. The retained digesta (150 g wet weight) was washed with 2.2 L pre-warmed McDougall’s buffer to remove particle associated microorganism (PAO). The SRF and the PAO were then filtered through 8 layers of cheesecloth, separately, and mixed at a ratio of 1:2 (SRF:PAO). The SRF:PAO mixture for each steer was incubated with the TMR containing HTM and a separate incubation with the TMR containing STM for 0, 12, and 24 h (3 replicate in vitro tubes/animal/TMR treatment) at 39°C under anaerobic conditions. After each incubation time, samples were centrifuged at 1,500 x g. The supernatant was removed and frozen at -20°C for VFA analysis. The digesta pellet was dried at 60°C and DM, NDF, and ADF digestibility determined. Data were analyzed as a completely randomized block design with individual animal as the experimental unit. There was a treatment x day x sample type interaction for rumen Zn (P < 0.04) and Mn (P < 0.03) concentrations. Zinc and Mn concentrations were greater in digesta and lesser in supernatant in STM compared with HTM supplemented animals. Rumen distribution of Cu was not impacted by TM source. In vitro molar proportions isobutyric acid were greater (P < 0.01) in HTM compared with STM supplemented animals, while the molar proportion of propionic acid were greater (P < 0.01) in STM supplemented animals. Total VFA concentration, molar proportions of acetic and propionic acid, and DM, NDF, and ADF digestibility were not impacted by dietary trace mineral source or rumen fluid source. These data may indicate that the source of trace mineral can influence trace mineral solubility in the rumen.
PSVI-7 Snorna Dysregulated Expression and Potential Roles in Bovine Sub-Clinical Mastitis Due to Staphylococcus Chromogenes
Authors: Omonijo Faith A , Gagné David , Laterrière Mario , Ster Celine , Zhao Xin , Ibeagha-Awemu Eveline M
Published: November 2023

Staphylococcus chromogenes (SC), a frequent non-aureus staphylococcus on Canadian herds causes both clinical and subclinical forms of mastitis and contributes to large economic losses on Canadian farms. However, little research attention has been directed to uncovering the molecular mechanisms underlying SC mastitis pathogenesis, including the roles of small nucleolar RNAs (snoRNAs). SnoRNAs function to regulate host ribosomal RNAs (rRNAs) biogenesis and processing, and are known to have regulatory functions in several human diseases, but no study has examined their regulatory functions in bovine mastitis. To understand the regulatory roles of snoRNAs in cows with SC subclinical mastitis, the snoRNA transcriptome of milk somatic cells from three SC infected cows [positive for SC only, have high somatic cell counts (SCC ≥350,000 cells/mL) for ≥ 3 months consecutively, only one positive udder sampled], and four healthy cows [low SCC (< 100,000 cells/mL) for ≥3 months consecutively, compositive sample of all quarters] was characterized by sequencing and bioinformatics analysis. Among 232 known snoRNAs found in the samples, 33 were differentially expressed (DE; 14 downregulated and 19 upregulated; FDR < 0.05). Out of these, SnoRA3/snoRA45 (upregulated) belongs to H/ACA snoRNA box type while SNORD14 (downregulated) belongs to C/D box snoRNA box type. According to RNAsnoop analysis, SnoRA3/snoRA45 interacted with 18S-1667 rRNA [minimum free energy (MFE) = -36Kcal/Mol] while SNORD14 interacted with 28S-3926 rRNA (MFE = -15.40Kcal/Mol). The observed strong MFE suggests that SnoRA3/snoRA45 and SNORD14 might potentially participate in rRNA modifications which could affect important functional sites of the ribosome with implications on the pathogenesis of bovine SC mastitis. SnoRA3/snoRA45 have been reported to guide site specific pseudouridylation of rRNA by upregulating the ribosomal pathway as well as have important roles in cell cycle progression in human. SNORD14 is expressed from the intron of its host gene RPS13, which is a ribosomal protein involved in protein biosynthesis. Also, SNORD14 has been shown to be potentially involved in intracellular protein transport and positive regulation of MAPK cascade. Our results suggest that the DE snoRNAs could potentially regulate the host rRNA biogenesis and processing in response to mastitis due to SC. To the best of our knowledge, this is the first study to report dysregulated snoRNA expression and potential involvement in bovine SC subclinical mastitis.
PSXII-25 Examining Relationships Between Residual Feed Intake Classification, Enteric Emissions, and Apparent Total Tract Digestibility in Yearling Beef Heifers
Authors: Acton Kortney , Duarte Marcio S , Swanson Kendall C , Ellis Jen L , Wood Katharine M
Published: November 2023

Improving feed efficiency in beef heifers may help reduce enteric emissions and improve economic returns for producers. The objective of this project is to assess the relationship between traditional residual feed intake (RFI) efficiency classification, enteric gas emissions, and apparent total tract nutrient digestibility in growing yearling heifers. Angus crossbred heifers (n = 74, BW = 408 ±27.1 kg) were blocked by BW and randomly assigned to pen groups. All heifers were fed a common haylage-based diet for ad libitum intake. Insentec feeding stations (Insentec B.V., Marknesse, The Netherlands) were used to measure individual feed intake and feeding behavior data. To measure enteric gas emissions of methane (CH4), carbon dioxide (CO2), and oxygen (O2), heifer groups were rotated through pens with GreenFeed trailers (C-Lock Inc., Rapid City, SD, USA) weekly. Apparent total tract digestibility was determined by collecting fecal samples from each heifer every 9 h over three days, composited and dried at 65 °C for 96 h, and analyzed for nutrient values (A&L Canada Laboratories, London, ON, Canada). Nutrient digestibility was determined for each heifer using acid-insoluble ash (AIA) and undigestible neutral detergent fiber (uNDF) as internal markers. RFI was determined using a regression of midpoint BW and ADG and then heifers were ranked by RFI quartile group. Data were analyzed using PROC GLIMMIX in SAS, with efficiency quartile group as the fixed effect and pen as a random effect, comparisons between quartile groups were assessed with a Tukey test. As expected, efficient (least RFI) heifers had decreased dry matter intake (8.5 vs 10.1 ± 0.20 kg/d, P < 0.01), less bunk visits (70 vs 112 ± 6 visits/day, P < 0.01), spent greater time per visit (2.46 vs 1.31 ± 0.249 min/visit, P < 0.01), and consumed more feed per visit (145 vs 104 ± 11.9 g DM/visit, P < 0.03), which resulted in a faster eating rate (65 vs 98 ± 5.0 g DM/min, P < 0.01), and produced decreased enteric CO2 emissions (7,653 vs 8,120 ±122.6 g/d, P = 0.05) compared with inefficient (greatest RFI) heifers. Additionally, when using AIA as the internal marker, efficient heifers showed greater digestibility of organic matter (89.8 vs 91.4 ± 0.49 %, P = 0.02) and NDF (20.2 vs 30.0 ± 2.66 %, P = 0.04) apparent total tract digestibility, while using uNDF as the internal marker showed no difference (P > 0.20) between efficiency groups. These data indicate that more efficient yearling heifers consume less feed, have reduced enteric gas emissions, and have improved organic matter and NDF apparent total tract digestibility.
PSXII-21 Post-Weaning Impacts of Late Gestation Maternal Feed Restriction on the Calf Rumen Microbiome
Authors: Woodruff Kelly L , Williams Jordan D , Hummel Gwendolynn L , Lake Scott L , Cunningham-Hollinger Hannah C
Published: November 2023

Maternal gestational nutrition is known to impact gut physiology and the gut microbiome of offspring early in life; however, it remains unknown if these changes persist later in life. We hypothesized that the impacts of maternal feed restriction in late gestating beef cows on early colonization of the calf gut would impact the rumen microbiome post-weaning. Our objective was to compare the post-weaning rumen microbiome of calves born with feed restricted dams and those born to dams with adequate nutrition. Starting roughly 60 d before expected calving, dams were stratified to either receive 100% of NRC requirements (CON) or 70% intake of NRC requirements (FR) through 28 d post-parturition. Pairs were then moved on to native grass until weaning. Rumen fluid was collected from the calves at the time of weaning (PRE) and after a 70 d backgrounding feed efficiency study (POST). Microbial DNA was isolated and the V4 region of the 16S rRNA was sequenced on the MiSeq platform. Data were analyzed within each time point using QIIME2. Maternal treatment had no impact on alpha diversity (Faith’s phylogeny, Shannon’s diversity, and Evenness) in the PRE group, but CON calves had greater (q = 0.05) evenness than FR calves in the POST samples. There were differences in composition between CON and FR in the PRE samples (unweighted unifrac q = 0.04; bray-curtis q = 0.03). No differences (q ≥ 0.14) in composition were found in the POST samples. These data indicate that at the time of weaning (PRE) differences in composition existed in CON vs. FR calves, specifically in the rare taxa, but the microbial composition converged by the end of the feeding trial. Interestingly, previous findings in our lab reported differences in alpha and beta diversity 28 d after birth in these calves. Together, these data indicate the potential for long-term impacts of maternal nutrition on the gut microbiome. This coupled with the previously published work where feed efficiency tended to differ between CON and FR, suggests that early perturbations during gestation may have had lasting impacts on gut physiology and subsequent performance in the presence of rumen microbial shifts.
PSIX-6 The Effects of Hydrolyzed Protein on Macronutrient Digestibility, Fecal Metabolites, Oxidative Stress and Inflammatory Biomarkers, and Skin and Coat Quality in Adult Dogs
Authors: Hsu Clare , Marx Fabio , Guldenpfennig Ryan , de Godoy Maria R C
Published: November 2023

Research on protein hydrolysates has observed various properties and functionalities of these ingredients depending on the type of hydrolysate. The objective of this study was to evaluate the effects of hydrolyzed chicken protein that was incorporated into diets on digestibility, gut health, skin and coat health, oxidative stress, and inflammation in healthy adult dogs. Five complete and balanced treatment diets were manufactured: 1) CONd: chicken meal diet; 2) 5% CLHd: 5% substitution of chicken liver hydrolysate of chicken meal diet; 3) CLHd: chicken liver hydrolysate diet; 4) 5% CHd: 5% substitution of chicken hydrolysate of chicken meal diet; and 5) CHd: chicken hydrolysate diet. A 5×5 Latin square design was used which included 10 neutered adult beagles. Each of the 5 periods consisted of a 7-d washout time and a 28-d treatment period. All diets were well accepted by the dogs. There was greater (P < 0.05) fecal butyrate (226.8 μmol/g DMB) concentration as well as decreasedr isovalerate (6.8 μmol/g DMB), 4-ethylphenol (1.4 μmol/g DMB), and indole (0.7 μmol/g DMB) in dogs fed CLHd than CONd (149.3, 10.8, 2.5, and 1.5 μmol/g DMB, respectively). Doges fed CHd had greater (P < 0.05) fecal immunoglobulin A concentration (2.86 mg/g) when compared with CLHd (0.91 mg/g); however, both groups were comparable to the control. There was no difference among groups in serum cytokine concentrations, serum oxidative stress biomarkers, or skin and coat health analyses (P > 0.05). In conclusion, chicken protein hydrolysate could be incorporated into canine extruded diets as a comparable source of protein to traditional chicken meal. The test chicken protein hydrolysates may have potential to support gut health by modulating immune response and fermentative activity; however, more research is needed to confirm the effect.
PSVIII-9 Consumer Acceptance of Corn Fermented Protein Compared with Traditional Yeast and Dried Distillers Grain in Extruded Dog Food
Authors: Kim Hee Seong S , Kilburn-Kappeler Logan , Yang Gongshun , Koppel Kadri , Aldrich Charles G G
Published: November 2023

Sustainability is one of the trending keywords in the pet food industry today. Utilizing protein-rich fermented co-products such as corn fermented protein (CFP) can promote sustainable pet food. However, co-product ingredients have been avoided in pet food due to negative consumer perception. Unlike traditional dried distillers grain, corn fermented protein (CFP) contains 50% protein due to a substantial yeast component, which may improve consumer perception. The objective was to evaluate the effect of CFP inclusion in dry dog food on consumer acceptance. Treatments included a control diet (CON, no fermented co-products), a brewer’s dried yeast diet (BDY, 3.5% brewer’s dried yeast), a distillers dried grains with solubles plus brewer’s dried yeast diet (DDGS+BDY, 17.5% DDGS + 2.5% brewer’s dried yeast), and a corn fermented protein diet (CFP, 17.5% corn fermented protein). The consumer acceptance data were collected from 104 dog owners who purchased dry dog food and feed their dogs during a central location test. Data were collected using RedJade software and analyzed by one-way ANOVA (Sensory XLStat package) to determine significant differences among overall appearance, color, aroma, and assumed dog liking. The effects were assessed using Fisher’s Least Significant Difference with significance at P < 0.05. All treatments were equally liked (P > 0.05) based on 9-point scale. More consumers showed liking in aroma for yeast containing treatments (CFP, n = 51; DDGS+BDY, n = 46; BDY, n = 45) than CON (n = 37). Consumer opinion of pet food ingredients were also evaluated. Chicken and salmon were considered most appropriate (> 85%) by consumers, while brewer’s dried yeast, corn meal, yeast, and corn gluten meal were considered appropriate from less than 10% of consumers. The most inappropriate ingredients according to consumers were corn gluten meal (>50%), corn meal, brewer’s yeast, dry yeast, and yeast. In conclusion, consumers liked the kibble that contained BDY, DDGS, or CFP at the same level as the control diet when evaluated based on sensory perceptions. However, there is a need to improve consumer perception of corn and yeast ingredients to promote sustainable pet foods.
PSVIII-15 Saccharomyces Cerevisiae Fermentation Product Influences Indicators of Gut Health and Function in Healthy Adult Cats
Authors: Norton Sharon A , Lin Ching-Yen , Naqvi S Ali , Chakrabarti Anirikh , Sardi Maria I , Franz Nolan
Published: November 2023

Compared with other species, the gastrointestinal influences of dietary Saccharomyces cerevisiae fermentation product (SCFP) in cats are not well-characterized. In this study, SCFP (TruMune, Cargill, Inc.) was added to an extruded cat food to explore gut-related outcomes in healthy adult cats. Sixty-three cats (mean age = 6.3 ± 2.8 yr; mean BW = 4.4 ± 0.1 kg) were used in a randomized complete block design to evaluate a base diet without SCFP (CON) or supplemented with 150 mg/kg BW SCFP (TRUL) or 300 mg/kg BW SCFP (TRUH). All cats were fed CON during a 21-d adaptation period and subsequently fed their respective diet from d 0 to d 42. Fecal samples were collected at d 0, d 21 and d 42 for analysis of fecal characteristics, fermentation end-products and shotgun metagenomics. A 5-d total fecal collection was performed from d 35 to d 39 for analysis of apparent nutrient digestibility. Data were analyzed using R v.4.1.2. Non-metagenomic data were analyzed using linear and generalized linear mixed models with lme4 and emmeans packages and metagenomic data were analyzed using phyloseq, vegan, lme4, LinDA and emmeans packages. Differences P < 0.05 were considered significant and P < 0.10 as trends after FDR correction. Fecal pH was higher (P = 0.01) for SCFP-supplemented cats vs CON and exhibited a positive linear dose response (P < 0.05) at d 21 and d 42. Fecal score was higher (firmer; P = 0.05) for SCFP-supplemented cats vs CON at d 21 consistent with a linear decrease (P = 0.02) in the binary comparison of fecal moisture between CON vs SCFP-supplemented cats (P = 0.01) during total fecal collection. Fecal ammonia demonstrated a quadratic treatment dose response trend at d 21 (P = 0.09). Fecal butyrate decreased linearly with SCFP dose (P < 0.001) and was less (P < 0.05) for SCFP-supplemented than CON cats at d 21 and d 42. Total short-chain fatty acid (SCFA) decreased linearly (P = 0.08) with SCFP dose and was less (P = 0.05) for SCFP-supplemented than CON cats at d 21. Species level alpha diversity decreased for CON (P = 0.04) but did not change in the TRUL and TRUH groups. Shannon diversity tended to increase in TRUH (P = 0.08) among a subset of 25 butyrate producers identified by the presence of butyrate pathway enzymes. Differential abundance of butyrate producers showed Acidaminococcus timonensis; CAG-83 sp900545495 and Megasphaera elsdenii decreased while Butyricicoccus pullicaecorum and Lawsonibacter 1402 linearly increased over time for TRUH cats (P < 0.05). No differences in alpha diversity or abundance were detected for any other butyrate producing taxa in TRUH nor between CON and TRUL cats. These results suggest SCFP influences several gastrointestinal outcomes in adult cats including pathways associated with SCFA production, cross-feeding, and/or absorption.
PSII-19 A Satellite-Based Decision-Support Tool to Optimize Profitability and Environmental Stewardship of Cow-Calf Operations
Authors: Adams Jordan M , Fernandes Jr. Jalme , Fernandes Marcia , Reis Ricardo , Tedeschi Luis O
Published: November 2023

Management strategies implemented in cow-calf operations are essential to capitalize on heavier feeder calves, but field data collection can restrict their practical application. A computer program to optimize weaning weight, profitability, and environmental sustainability of grazing cow-calf operations was developed by combining an existing mechanistic nutrition model with pasture biomass estimated using satellite images. Data from the Texas A&M University McGregor Research Center was used as a testbed for the computer model. Pasture forage data from 2016 to 2022 was collected via satellite imagery, and the predicted pasture biomass was adjusted based on third-party algorithms (Sigfarm Intelligence LLC). Nutrient requirements were estimated using the Ruminant Nutrition System (RNS), and a constant pasture nutritive value was obtained. The potential dry matter intake (DMI) was estimated from the initial herd size (input). Actual average weaning weight was used to predict cow milk yield and total metabolizable energy requirements, which was used to estimate the required DMI (DMR). The actual forage allowance was correlated to DMR, and we simulated the forage allowance to support increased DMI and, consequently, increased milk yield to achieve a targeted average weaning weight. Based on Intergovernmental Panel on Climate Change (IPCC) methodology, environmental impact was evaluated from greenhouse gas emission estimates. Our simulations demonstrated that increasing the target weaning weight of a smaller herd with fewer mature cows (757 cows) would produce heavier calves, resulting in a 6% decrease in calf gain per pasture area. Nevertheless, the net income increased in scenarios with heavier weaned calves. The enhanced productivity with heavier weaned calves and fewer cows resulted in a lower carbon emission per kg of produced weaned calves. Based on our simulation, a herd size between 757 and 812 mature cows yielding calves weaned between 280 and 300 kg would be an optimal management strategy for the studied operation. This computer model provides the fundamental framework for a decision-support tool for producers to optimize their cow-calf operations while producing ideal weaned calves for feedlot operations.