bluuebunny/crossref_metadata_2025_split huggingface dataset:
347 Enteric Methane: Current Measurement and Assessment Techniques
Authors: Hristov Alexander N 
Published: October 2021

Abstract
Enteric methane (ECH4) emissions from ruminants can be measured directly or indirectly using various techniques and recent reviews have discussed advantages and disadvantages of these techniques. The GLOBAL NETWORK project (GN; an international consortium of animal scientists) examined techniques for measuring ECH4, including respiration chambers, the sulfur hexafluoride tracer (SF6) technique, and techniques based on short-term measurements of gas concentrations in samples of exhaled air. The latter category includes automated head chambers (i.e., the GreenFeed system; GF), use of carbon dioxide as a marker, and (handheld) laser methane detection. The conclusion from this analysis was that “there is no ‘one size fits all’ method for measuring ECH4 emission by individual animals” and appropriate and frequent calibrations and recovery tests are necessary with all methods. The team also concluded that the need for screening large numbers of animals (for example, for genomic studies), does not justify the use of measurement methods that are inaccurate. Timing of sampling/data collection is critical for the spot-sampling techniques, such as GF. It is a well-established fact that ECH4 emission is closely related to animal’s dry matter intake (DMI) and feeding patterns. Therefore, data collection using GF has to be sufficiently long and frequent, during both day and night hours, to fully represent the diurnal patter of ECH4 emission. The in vitro gas production and analysis technique can be used to screen feed additives or other ECH4 mitigation treatments, but data must be always confirmed/supported by animal (preferably long-term) studies. ECH4 emission can be also predicted based on dietary or animal variables. Large databases developed by the GN project have confirmed that DMI is driving ECH4, but other factors, such as dietary neutral detergent fiber, milk yield and composition (dairy cows), or dietary forage inclusion and animal’s body weight (beef cattle) can improve prediction accuracy.
356 Anomalies of Carbohydrate Digestion and Metabolism by Ruminants
Authors: Owens Fredric N 
Published: October 2021

Abstract
Carbohydrate, derived either from plant cell walls (neutral detergent fiber; NDF) from fresh or conserved forages consumed by cows and growing cattle or from starch of grains and concentrates in commercial feedlot diets, provides most of the dietary energy for ruminant growth and production. The ruminants’ ability to harvest forage from remote, inaccessible locations, to scavenge energy from NDF of feeds and byproducts of grain largely indigestible by non-ruminants, and to employ non-protein N to form protein-rich, nutrient-dense foods for humans are key ecological advantages over non-ruminants. Outlined below are some topics needing research attention. First, feed composition tables invariably indicate that the digested energy (DE) of carbohydrates is 4.4 kilocalories per gram, yet the gross energy (GE) of purified carbohydrate polymers (starch; cellulose, glycogen) averages 4.18; monomers (hexoses, pentoses) average 3.74. Having DE exceed GE violates the first Law of Thermodynamics! Might this 5 percent discrepancy reflect underestimations of fecal lignin or of protein digestibility due to metabolic fecal N? Favoring feeds rich in carbohydrate, this discrepancy confounds formulation of least-cost diets. Secondly, site of digestion of carbohydrate alters its metabolizable energy (ME). Fermentation, though required to yield ME from NDF, generates methane and heat. In contrast, starches and sugars that escape ruminal fermentation, if digested in the small intestine, circumvent these losses increasing their relative ME. Unfortunately, when ruminally fermented, starch, either directly or via pH depression, reduces NDF fermentation; might ruminal NDF digestion be increased by feeding NDF plus buffer versus concentrate diet components asynchronously? Third, carbohydrate metabolites lost in urine (lactate, pentoses, hippuric acid) need further quantification. Finally, ruminally-formed metabolites (methylglyoxal, methane) adversely affect animal health and energetics. Ruminal modification (site- or time-targeted enzymes or inhibitors; altering the ruminal microbiome with pre- or probiotics, inoculants, nutraceuticals) should help enhance ruminant productivity and sustainability.
355 Mineral Metabolism
Authors: Spears Jerry W 
Published: October 2021

Abstract
This presentation will highlight historic discoveries in mineral metabolism in ruminants. At least 15 minerals can be classified as essential based on their involvement in one or more metabolic functions in mammals. Deficiencies of all essential minerals have occurred naturally or have been induced experimentally in ruminants. Cobalt was shown to be essential for ruminants in 1935 based on its ability to correct naturally occurring deficiency signs in Australia. This discovery occurred 13 years before cobalt was shown to a component of vitamin B12. Low serum magnesium concentrations also were associated with grass tetany in cattle before magnesium was found to be essential for the rat in 1931. The value of supplemental salt for cattle was demonstrated in the 1800’s and a salt deficiency was experimentally induced in dairy cows in 1905. Over 50 years later sodium was identified as the mineral primarily responsible for salt deficiency. Naturally occurring deficiencies of phosphorus and copper were observed in grazing ruminants shortly after they were reported to be essential for rats. Copper toxicosis also became recognized as a practical problem, especially in some breeds of sheep. Selenium was shown to prevent white muscle disease in 1958. Because of its known toxicity and lack of a specific metabolic function, it was not until 1979 that Food and Drug Administration approved the addition of 0.1 mg Se/kg DM (later increased to 0.3 mg/kg) from inorganic sources to ruminant diets. This approval occurred after the identification of glutathione peroxidase as a selenium metalloenzyme in 1972. In 2009, the Food and Drug Administration approved the use of chromium propionate as a source of supplemental chromium for cattle at levels up to 0.5 mg Cr/kg DM. The approval of chromium propionate was based on its safety and ability to enhance insulin sensitivity in cattle.
358 Effect of Molasses Type on Pre-weaning Lamb and Ewe Performance
Authors: Harrelson Patricia L , Harrelson Flint W , Runnels Montana , Reed Audrey 
Published: October 2021

Abstract
The objective of this study was to investigate the effects of form of molasses on lamb and ewe performance. Creep feeding of lambs is essential to lamb growth, rumen development, and reduction of milk production from dams. Molasses is often added for increased palatability and energy. Crossbred lambs (n = 47; average age = 30 d) and their accompanying dams (n= 35) were assigned to one of two treatments using a completely randomized design with similar distributions of single and twin-born lambs and sexes. Treatment diets were formulated to be isonitrogenous and contained either wet (WMOL) or dry (DMOL) molasses. Dry molasses was added at 10% of the diet DM, whereas, wet molasses was added at 14.3% of the diet DM. Lambs were fed creep rations for 42 d prior to weaning. Creep feed was provided ad libitum and mixed grass hay was offered free-choice. Lamb weights were recorded weekly until weaning (d 42) and ewe BCS was measured at d 0 and d 42 (weaning). Overall lamb ADG was comparable (DMOL = 0.268 kg/hd, WMOL = 0.293 kg/hd; P = 0.30). Lamb weaning weights were similar between DMOL and WMOL (DMOL = 27.9 kg; WMOL = 27.5; P = 0.79). Ewe BCS was similar (P = 0.88) between DMOL and WMOL at 1.4 and 1.4, respectively. Estimated creep intake was calculated based upon total consumption following the end of the project and was found to be similar between treatments (DMOL = 0.54 kg/hd/d; WMOL = 0.59 kg/hd/d). Lamb pre-weaning growth and ewe performance was similar between DMOL and WMOL. Further research is needed to further explore the economic impact and use post-weaning.
362 Summary of North Carolina Small Ruminant Producer Performance Record Collection Questionnaire
Authors: Weaver Andrew R , Shaeffer April D 
Published: October 2021

Abstract
Growing interest and demand for small ruminant production in the Southeastern United States has garnered the need for improved productivity and greater Extension education programs. To better understand North Carolina small ruminant producer performance record collection, a needs assessment questionnaire was conducted. An online questionnaire was sent to sheep and goat producers via Extension email lists and state producer organizations. Producers were given nine weeks to respond to the survey and provided three email reminders. All responses were anonymous. The survey reached approximately 1200 producers. Of those, 131 agreed to the consent form, indicated they owned sheep and/or goats, and completed subsequent questions. A portion of respondents did not answer all questions. Of the 76 goat producers, 75.0% had 25 or less mature breeding females. Of the 75 sheep producers, 58.7% had 25 or less mature breeding females. Twenty producers had both sheep and goats. The portion of producers recording birth (62.6%) and rear (42.7%) type data on their entire flock was numerically greater than those recording birth (29.0%) and weaning (16.8%) weights on their entire flock. In terms of FAMACHA scores, 19.8% record data on their entire flock compared to 41.2% that record some data and 22.1% with no records. 45.8% of producers indicated no fecal egg count (FEC) records with 27.5% recording some FEC data. In terms of genetic selection tools, 41.2% of producers had not heard of estimated breeding values (EBVs) compared to 39.7% that indicated a basic understanding and 3.8% that use EBVs. This aligns with the 44.3% of producers that have not heard of the National Sheep Improvement Program and 38.2% that have a basic understanding. These data indicate the need for greater collection of performance records and participation in genetic evaluation programs among small ruminant producers in North Carolina.
360 Body Temperature of Hair Sheep Ewes During the Postpartum Period and Around the Time of Mating in an Accelerated Lambing System in the Tropics
Authors: Godfrey Robert , Lakos Sue A 
Published: October 2021

Abstract
The study was conducted to evaluate body temperature of hair sheep ewes at various stages of the production cycle in an accelerated lambing system in the tropics. Multiparous St. Croix White (STX: n = 7) and Dorper x STX (DRPX; n = 7) ewes lambing in October and raising single lambs weaned at 120 d were used. Synchronized breeding began at 96 d postpartum. Vaginal temperature (VT) was measured at 10-min intervals for 96 h at 38 and 66 d post-partum (PP1, PP2) and at 2 days after mating (PM) using data loggers. Daily minimum, maximum and range of VT were determined for ewes within PP1, PP2 and PB. Data were analyzed using GLM procedures of SAS with breed, day and time (PP1, PP2, PM) in the model. Mean ambient temperature, temperature-humidity index and solar radiation at PP1, PP2 and PM were 24.8 °C, 25.2 °C, 23.8 °C, and 74.7, 74.9, 73.3, and 180 W/m2, 160 W/m2 and 155 W/m2, respectively. Minimum VT was lower (P &lt; 0.002) in STX than DRPX ewes at PP1, PP2 but not PM (38.27 ± 0.04 vs 38.44 ± 0.04 °C, 38.16 ± 0.04 vs 38.33 ± 0.04 °C, 38.47 ± 0.04 vs 38.58 ± 0.04 °C, respectively). There was no difference in maximum VT between breed or time (P &gt; 01.0). There was no breed difference (P &gt; 0.10) in range of VT, but the range of VT was lower (P &lt; 0.0001) at PM compared to PP1 and PP2 (1.22 ± 0.04 vs 1.77 ± 0.04 vs 1.63 ± 0.04 °C, respectively). These results show that tropically adapted STX ewes have lower body temperatures, as shown by the lower minimal VT which indicates a degree of nighttime cooling, during the postpartum period compared to DRPX ewes in a tropical environment.
513 Late-Breaking: Effects of Dietary Protein Content and Crystalline Amino Acid Supplementation Patterns on Gut Health of Weaned Pigs Raised Under Different Sanitary Conditions
Authors: Lee Jinyoung , Vega Caroline Gonzalez , Htoo John K , Yang Chengbo , Nyachoti Martin 
Published: October 2021

Abstract
The objective of this experiment was to investigate the effects of dietary crude protein (CP) content and crystalline amino acids (CAA) supplementation patterns on the histomorphology, immune response, and microbial metabolites in weaned pigs under clean (CSC) or unclean sanitary conditions (USC). One hundred forty-four piglets (6.35 ± 0.63 kg BW) were assigned to 1 of 3 diets: a high CP (HCP; 21%) and two low CP (LCP; 18%) diets supplemented with 10 crystalline indispensable amino acids (IAA) to meet all IAA requirements or only 6 IAA (Lys, Met, Thr, Trp, Val, and Ile) to meet IAA requirements except for Leu, His, and Phe. Each treatment had 8 replicates per sanitary condition with 3 pigs per pen. The CSC room was cleaned and washed weekly, whereas the USC room remained unwashed throughout the experiment and had sow manure spread in the pens. Data were analyzed using the MIXED procedure of SAS with orthogonal contrasts. Pigs fed the LCP diets had longer (P &lt; 0.05) jejunal villi and higher villus height to crypt depth ratios than those fed the HCP diet. No significant difference is found in histomorphology between pigs fed LCP diets with different CAA supplementation patterns. Pigs raised under USC had greater (P &lt; 0.05) plasma interleukin (IL)-10 and IL-6 concentrations and reduced (P &lt; 0.05) plasma tumor necrosis factor-alpha concentration. Also, the LCP diets resulted in a greater (P &lt; 0.05) plasma IL-10 concentration. Interactions (P &lt; 0.05) between sanitation and dietary CP content were observed for goblet cell density and acetate and total volatile fatty acids contents in the jejunum. In conclusion, CAA supplementation patterns did not affect gut morphology in weaned pigs. Feeding LCP diets to weaned pigs improved gut morphology and microbial metabolites in jejunum under USC and ameliorated systemic inflammation induced by USC.
507 Late-Breaking: Heat Stress and Mitoq Supplementation Impact Skeletal Muscle Mitochondrial Capacities in Pigs
Authors: Wesolowski Lauren T , Guy Chloey P , Mayorga Edith J , Rudolph Tori E , Freestone Alyssa D , Rhoads Robert P , Baumgard Lance H , Selsby Joshua T , White-Springer Sarah H 
Published: October 2021

Abstract
Heat stress can negatively impact pig health and performance but the effects of heat stress on skeletal muscle mitochondrial function are largely unknown. We hypothesized that mitochondrial function and capacity would be impaired in heat stressed (HS) compared to thermoneutral (TN) pigs but mitochondrially-targeted coenzyme Q (MitoQ) supplementation would rescue the impairment. Oxidative portions of the semitendinosus muscle were evaluated from TN and HS gilts receiving no supplementation (CON) or MitoQ for 2 d prior to and during the 24h environmental heat treatment (n = 8 per group). Mitochondrial oxidative phosphorylation (P) and electron transfer (E) capacities were determined via high resolution respirometry and mitochondrial volume density and function were quantified by citrate synthase (CS) and cytochrome c oxidase activities, respectively. Data were analyzed using linear models in SAS v9.4 with fixed effects of heat, MitoQ treatment (trt), and heat×trt interaction. There were trends for the interaction of trt and heat (P≤0.1) on integrative (per mg tissue) and intrinsic (relative to CS) P with complexes I and II (PCI+II), maximum noncoupled E (ECI+II), and E with complex II only (ECII), in which all measures were greater in HS-MitoQ than TN-MitoQ (P≤0.03), but measures did not differ due to HS in CON pigs. The contribution of leak to total E (flux control ratio, FCRLeak) was lesser in HS-MitoQ than HS-CON, TN-CON, and TN-MitoQ (P≤0.02). The FCRPCI was greater (P≤0.05) while the FCRPCI+II was lesser (P=0.01) in TN compared to HS pigs. Finally, the FCRPCI+II was greater (P=0.02) while the FCRECII tended to be lesser (P=0.09) for CON than MitoQ pigs. Neither mitochondrial volume density nor function were affected by HS or MitoQ supplementation. In total, these data indicate improved mitochondrial capacities following heat stress in pigs receiving MitoQ but no difference in mitochondrial capacities in unsupplemented, HS pigs.
516 Late-Breaking: Iturin a Protects the Intestinal Mucosal Integrity Against E. coli Containing the Gene Coding for Heat-stable Enterotoxin B
Authors: Zhou Jia-yi , Liu Zhen-hua , Gao Chunqi , Yan Huichao , Wang Xiu-qi 
Published: October 2021

Abstract
Enterotoxigenic E. coli causes severe infectious diarrhea with high morbidity and mortality in weanling pigs mainly through the production of heat-stable enterotoxins. Iturin A, originally isolated from the insect Hyalophora cecropia, exerts strong antibiotic activity against Gram-positive and Gram-negative bacteria. Thus, our study investigated whether iturin A could protect the intestinal epithelium from the insults of E. coli Rosetta containing the gene coding for heat-stable enterotoxin b (STb-Rosetta). Twenty-eight piglets were divided into four groups and were orally administered PBS (control), 0.16 g/kg BW iturin A, 2 × 109 CFU STb-Rosetta, and 0.16 g/kg BW iturin A + 2 × 109 CFU STb-Rosetta respectively for 8 days. The intestinal epithelial morphology and barrier function were assessed by H&E staining and Ussing chamber, and the growth advantage in enteroids derived from jejunal crypts of piglets in each group was used to evaluate the intestinal stem cell (ISC) activity. The results showed that iturin A increased the average daily gain (ADG) and average daily feed intake (ADFI) of piglets exposed to STb-Rosetta (P &lt; 0.05). Meanwhile, STb-Rosetta-induced decrease in jejunum weight and damage to jejunal morphology and barrier function were significantly improved after iturin A supplementation (P &lt; 0.05). Furthermore, the jejunal crypt cells from piglets in the iturin A + STb-Rosetta group had greater growth advantages of ISCs compared with the STb-Rosetta group, including enteroid forming efficiency, surface area, budding efficiency, and branching coefficient (P &lt; 0.05). Our results indicate that iturin A protects against STb-Rosetta-induced intestinal mucosal injury, which provides an intervention strategy that regulates the function of ISCs in the high turnover-rate crypt-villous axis under ETEC infection. This study was supported by the National Natural Science Foundation of China (31872389, 32072777) and Basic and Applied Basic Research Foundation of Guangdong Province (2019B1515210021).
509 Late-Breaking: Effect of a Sensory Additive on Sow Reproductive Performance
Authors: Davis Nathan , Tsia Tsungcheng , Bass Benjamin , Tedo Gemma , Morais Sofia , Maxwell Charles 
Published: October 2021

Abstract
The addition of a sensory additive to sow diets during the summer improved feed intake during lactation, and litter performance. The aim of this study was to evaluate the impact of the sensory additive on sow lactation performance during cooler temperatures. Three consecutive groups (n = 61 total) of sows were farrowed during winter (October, December and January). Sows were weighed, and back fat depth was measured, at 110 d of gestation prior to entering the lactation room, and again at weaning. The sows were sorted by parity, and then allotted by BW at d 110 to Control or 0.075% sensory additive (Luctamax® SowVive, Lucta S.A., Spain). Experimental diets were offered upon entry to the lactation room and fed through weaning. Feed disappearance was recorded every three days. Sows were fed 2.72 kg/head/day until farrowing, and then allowed to eat ad libitum from 24 hours post-farrowing until weaning. Data were analyzed using the PROC MIXED procedure of SAS as an RCBD with treatment as the fixed effect and group as a random effect. No differences were observed on sows feed intake (P &gt; 0.4), 10th rib backfat thickness change (P = 0.632) and body weight change from d 110 of gestation to weaning (P = 0.65, Table 1). Sows fed the sensory additive lowered preweaning mortality by 4.9% (P = 0.051), and weaned an additional 1.42 piglets (P = 0.026) with similar weaning weights (P = 0.86) when compared to control. In conclusion, in the current study, lactation diets supplemented with a sensory additive improved litter performance and helped maintain sow body condition.
475 The Effect of Increasing Total Sulfur Amino Acids to Lysine Level and Methionine Source on Growth Performance and Oxidative Parameters of Nursery Pigs Fed Oxidized Soybean Oil
Authors: Acosta Jesus A , Chen Ju Xing , Hancock Deana , Vásquez-Añón Mercedes 
Published: October 2021

Abstract
Total sulfur amino acids (TSAA): Lys level and Met source effects on growth performance and oxidative status were evaluated in nursery pigs fed oxidized soybean-oil. A total of 240 weaned pigs (BW=5.84± 0.96kg) were blocked by BW and randomly allotted to 60 pens. Treatments included a positive control containing fresh soybean-oil (PC) and 4 peroxidized soybean-oil treatments in a 2×2 factorial of 2 Met sources (DL-Met vs. 2-hydroxy-4-(methylthio)butanoate [HMTBa]) and 2 standardized ileal digestible TSAA: Lys levels (L1=0.58 vs. L2=0.65). Diets were fed for 42d. One pig per pen was euthanized at d42 for tissue analyses. Data were analyzed using PROC MIXED procedure of SAS. TSAA: Lys ratio did not affect ADG and ADFI. Met source did not affect ADG. HMTBa tended to increase ADFI compared to DL-Met (P = 0.08). There was a tendency for interaction between TSAA: Lys level and Met source for G: F (P = 0.07); pigs fed HMTBa-L1 tended to have decreased G: F compared to HMTBa-L2 and DL-Met-L1-L2. HMTBa had increased liver total antioxidant status (TAS) compared to DL-Met (P = 0.02). There was no TSAA:Lys level effect on TAS. Comparing PC to peroxidized treatments: pigs fed HMTBa-L1 and DL-Met-L1 tended to have decreased ADG (P ≤ 0.10) and DL-Met-L2 had decreased ADG (P &lt; 0.05) than PC. HMTBa-L2 was similar to PC. Pigs fed DL-Met-L1 had decreased (P &lt; 0.05) and DL-Met-L2 tended to have decreased ADFI (P ≤ 0.10) than PC. HMTBa-L1-L2 were similar to PC. All peroxidized treatments had similar G:F compared to PC. Pigs fed DL-Met-L2 tended to have decreased TAS compared to PC (P ≤ 0.10), but PC was similar to pigs fed DL-Met-L1 and HMTBa-L1-L2. In conclusion, under an oxidative challenge, HMTBa, at a TSAA: Lys ratio of 0.65, maintained nursery pigs’ growth performance and oxidative status.