bluuebunny/crossref_metadata_2025 huggingface dataset:
437 Fetal Programming in Sheep: Epigenetic modifications in offspring from poorly nourished dams
Authors: Tillquist Nicole M , Reed Sarah A , Zinn Steven A , Govoni Kristen E
Published: September 2024

Poor maternal nutrition (restricted- and over-feeding) during gestation can negatively impact the efficiency of livestock production by generating offspring with decreased muscle mass, increased adiposity, and impaired metabolism. The mechanisms behind these altered phenotypes are not well-characterized. The effects of poor maternal nutrition during gestation on offspring growth and development begin in utero and contribute to metabolic dysregulation of offspring into maturity and across subsequent generations, demonstrating long-term negative effects on the livestock. Fetal programming results in epigenetic modifications that can involve changes in offspring gene expression and downstream function, with no alteration on the DNA sequence. Using a sheep model of poor maternal nutrition, we have previously shown that F1 offspring from restricted- and over-fed dams are smaller at 10 mo of age relative to offspring from control-fed dams. Additionally, we observed that this phenotype persisted in the F2 offspring from restricted-fed granddams, while F2 offspring from over- and control-fed granddams were of similar body weight. We have recently demonstrated that F1 offspring from poorly nourished ewes have differential methylation patterns and altered gene expression in liver tissue demonstrating a potential mechanism that contributes to persistent altered growth. We have also begun evaluating the effects of maternal nutrient restriction on the development of fetal small intestine, a key facilitator of nutrient transport. Poor maternal nutrition during gestation alters development of offspring small intestine and further understanding of developmental programming in key metabolic tissues can aid in the development of nutritional strategies to improve efficiency of livestock production.
294 The use of dried bakery products as an alternative ingredient in dog food
Authors: Koulicoff Larissa A Alves , Aldrich Greg G , Pezzali Julia Guazzelli
Published: September 2024

Utilizing upcycling food materials that otherwise go to waste, such as dried bakery products (DPB), in pet food offers an opportunity to promote sustainability within the pet food industry. However, utilization of DBP as an ingredient in dog food has yet to be evaluated. This study aimed to assess the canine response to including DBP on extruded diets. Four diets were extruded containing 0% (control), 8.5%, 17% or 22.5% of DBP, replacing brown rice, lentil and sorghum (Table 1). Palatability was assessed using 20 dogs in a split-plate test with control presented against each other diet to determine intake ratio (IR) and first choice (FC). In a second study, experimental diets were fed to 12 adult Beagle dogs enrolled in replicated 4 x 4 Latin square design (9 d of diet adaptation and 5 d of sample collection) to evaluate apparent total tract digestibility (ATTD) of energy and macronutrients, and fecal characteristics. Statistical analyses were conducted using the GLIMMIX procedure in SAS with diet as a fixed effect, and square, dog nested within square and period as random effects. For palatability, IR was analyzed in a 1-way ANOVA and FC using a Chi2 test. Dogs did not (P > 0.05) have a preference when the control and 8.5% DBP diets were compared. However, they preferred (P < 0.05) the control over the diets with greater inclusion of DBP based on both IR and FC. In the second study, food intake was similar (P > 0.05) among all treatments. Dogs fed diets containing DBP had greater (P < 0.05) dry fecal outputs compared with those fed the control diet, but fecal quality scores remain within acceptable range. Inclusion of DBP quadratically decrease (P < 0.05) ATTD of dry matter, organic matter, protein, fat and gross energy, but coefficients were still within acceptable ranges (> 80%). No effect (P > 0.05) of dietary treatment was observed on fecal pH. Concentrations of fecal volatile fatty acids, however, were greater (P < 0.05) in dogs fed control compared with those fed 17% and 22.5% DBP, with dogs fed 8.5% DBP not differing (P > 0.05) from those fed the other dietary treatments. Nonetheless, there was no effect (P > 0.05) of diet on the relative proportion of each short chain fatty acid (acetate, butyrate, propionate) or branched chain fatty acid (valerate, isobutyrate and isovalerate). The findings of this study suggest that at 8.5% DBP can replace certain grains and legumes in extruded dog diets without affecting palatability and digestibility. Although greater inclusion of DPB reduced ATTD of macronutrients and energy, additional research is needed to determine the optimal amount of DBP to be used in combinations with other grains and legumes.
295 Synthesis of glycine from trans-4-hydroxy-L-proline in tissues of juvenile hybrid striped bass (Morone chrysops x M. Saxatilis)
Authors: Connolly Erin D , Suehs Blaine , Hissen Karina , Criscitiello Michael , Gatlin Delbert , Wu Guoyao
Published: September 2024

Trans-4-Hydroxy-L-Proline (Hyp) is a major amino acid in the collagen of fish. The turnover of collagen in various tissues releases a large amount of Hyp, which has traditionally been considered as a metabolic waste. However, results of recent studies have identified the conversion of Hyp into glycine in piglets. The present study tests this hypothesis that hybrid striped bass (HSB, a carnivorous fish species) can form glycine from Hyp. Fish were fed a standard diet containing 60% fishmeal for 10 wk and grew from 5.5 to 45 g during a 9-wk period. Slices (~75 mg) of skeletal muscle, liver, proximal intestine, gills, and brain were obtained from 45-g HSB (n = 6) and incubated at 26 °C for 2 h in 1 mL of oxygenated (95% O2/5% CO2) Krebs-Henseleit bicarbonate buffer (pH 7.4, with 5 mM D-glucose) containing 0, 0.2, or 2 mM Hyp. After a period of 2 h incubation, 200 μL of 1.5 M HClO4 was added into the incubation medium to stop the reaction. The acidified medium plus tissue together was homogenized and the homogenizer was rinsed with 1 mL of water, followed by the addition of 100 μL of 2 M K2CO3. The neutralized extract was analyzed for amino acids using HPLC involving o-phthaldialdehyde derivatization. Tissues without incubation were also determined for amino acids. Data were statistically analyzed by a paired t-test. Glycine was produced from 0.2 and 2 mM Hyp by the liver and skeletal muscle, and 2 mM Hyp by the intestine (Table 1). Glycine was further converted into serine in the liver, but not skeletal muscle or intestine. The production of glycine or serine from Hyp was not due to net protein breakdown in tissues. Tyrosine was measured as an indicator of protein degradation. There was no detectable generation of glycine from 0.2 or 2 mM Hyp by the gills or brain of HSB. These results indicate the synthesis of glycine from Hyp by juvenile HSB in a tissue-specific manner. Because skeletal muscle accounts for ~45% of the body weight, this organ is the major site for this metabolic pathway in the fish. (Supported by USDA/NIFA grant No. 2022-67015-36200)
303 Diets of Neolithic dogs
Authors: Bosch Guido , Cheung Lianne
Published: September 2024

The history of our modern-day pet dogs started around 40,000 yr ago in the Paleolithic era when humans had a hunter-gatherer lifestyle. During the period that humans became more sedentary agriculturalists, the Neolithic era, the food sources available for the early (proto) dogs living with humans also changed. The profound shift in the diet of dogs with increased amounts of cereal grains throughout this era is reflected in the genome of the dog, suggesting an enhanced digestive capacity to digest starch. The foraging strategies these dogs developed to meet energy and nutrient requirements are, however, still understudied. We therefore aimed to advance our understanding of the diets of Neolithic dogs. Data from various publications that included stable isotope, coprolite and observational analyses were retrieved and used to define hypothetical foraging strategies (scenarios). These strategies included commonly reported starch and protein sources and it was investigated how dogs met their dietary needs in terms of metabolizable energy (ME), nitrogen and indispensable amino acids. The ME contents were estimated based on the chemical composition using modified Atwater factors. Stable isotope and coprolite analyses suggest that Neolithic dogs had a highly variable diet, with a large variety in food items and differing ratios of plant-based food sources (e.g., millet, maize) to animal-based food sources (e.g., livestock, rodents). Observations support these findings with e.g. plant-based sources contributing 24 to 66% of the biomass and animal-based sources contributing 17 to 54%. Moreover, human feces are often noted in the literature as a food source for dogs with estimates 17 to 24% of the dietary biomass consumed. The ME requirement is shown to be easily met with the addition of animal-based feedstuffs and nitrogen requirements were always met if the dietary intake was sufficient to cover for minimum ME. However, several amino acids (e.g., Met and Cys) were limiting, if diet contained too little quantities of animal-based feedstuffs. Data from various publications and such scenarios provide context for the nutrition of present-day dogs and coprophagy commonly observed. In conclusion, Neolithic dogs developed an opportunistic foraging strategy resulting in diverse omnivorous diets. To support indispensable amino acids, dogs could not thrive solely on cereal-based diets but required to supplement these with animal-based food sources including human feces.
306 Oral therapy with specific bioactive collagen peptide (BCP) improves gait and quality of life in canine osteoarthritis patients
Authors: Dobenecker Britta , Böswald Linda , Reese Sven , Steigmeier-Raith Stephanie , Trillig Lukas , Oesser Steffen , Meyer-Lindenberg Andrea , Schunck Michael , Hugenberg Jutta
Published: September 2024

Conservative therapy options in canine osteoarthritis (OA) are largely limited to pain relief, which can be associated with undesirable effects. Beneficial effects of a specific BCP have been demonstrated in equine OA patients and in in-vitro studies with canine chondrocytes based on an increase in cartilage matrix molecules and downregulating of inflammatory cytokines and degenerative matrix metalloproteases1,2. A positive impact of specific BCP on joint cartilage was also detected by magnetic resonance imaging3. In a double blinded, placebo-controlled field study, effects of a 12 wk supplementation with this specific BCP vs. n3-fatty acids plus vitamin E (n3FA) on the gait were investigated in dogs with OA. The assessment of pet owners on the quality of life (QoL) was evaluated using the validated Canine Brief Pain Inventory4 Score. Privately owned adult dogs (n = 31) previously diagnosed with OA were randomly allocated to group BCP (PETAGILE, GELITA, Germany), n3FA, or placebo (PLA). The supplements were dosed according to body weight (BW; ≥ 200 mg BCP or PLA/kg BW; ≥ 550mg n3FA + 2mg vitamin E/kg BW). Inclusion criteria were a BW between 10 and 60 kg and restricted use of anti-inflammatory medication or nutraceuticals. Initially and after 12 wk, the dogs were examined on a custom-made treadmill equipped with 4 modified Kistler pressure plates. Differences between the groups, time points as well as the affected and contralateral limbs were evaluated using a generalized linear model. The improvement in QoL was greater in BCP than n3FA and PLA. The treadmill, as more objective method5, showed a significant difference of vertical force (PVF), vertical impact and standing phase between affected and contralateral limbs in group BCP. The improvement of the applied pressure, measured as relative difference of PVF, was significantly better in BCP as in PLA. In the placebo group, all measured parameters tended to worsen whereas in group n3FA no systematic differences between both time points were detected. The results of this study demonstrate that oral administration of a specific BCP can slow down the progression and improve clinical signs after only 12 wk in canine OA patients. Therefore, this safe nutritional therapy option should be considered in dogs with OA. References:[1] Dobenecker, B., Reese, S., Jahn, W. et al. (2018). J Anim Physiol Anim Nutr, 102, 16-23. [2] Schunck, M., Louton, H., & Oesser, S. (2017). J Anim Sci, 7, 254 [3] McAlindon, T. E., Nuite, M., Krishnan, N. et al. (2011). 19(4), 399-405. [4] Brown et al. (2008). J Am Vet Med Assoc, 233(8), 1278-1283. [5] Brown et al. (2013) J Vet Int Med, 27(1), 22-30.
35 Beneficial role of 1.3,.1.6 yeast beta glucan in pet health
Authors: Schulthess Julie , Leseaux Achraf A , Rabot Rodolphe
Published: September 2024

In recent years, 1.3, 1.6 yeast beta-glucans (BG) have gained increasing attention for their diverse health-promoting properties in both humans and animals. Yeast beta-glucans are polysaccharides known for their immunomodulatory effects, which have been extensively studied in various animal models. Especially when they are coming from yeasts, these polysaccharides exhibit the ability to train the innate immune system in particular monocytes and macrophages, enhancing phagocytosis, cytokine production, and overall immune response. A number of studies have already shown that 1.3, 1.6 yeast beta glucans can address several pet health specific concerns, such as periodontal disease, atopy, osteoarthritis, diabetes. At Phileo, we conducted a trial where canine monocytes and macrophages were trained with a proprietary 1.3, 1.6 yeast beta glucan to identify whether those canine phagocytes could benefit from the training by 1.3, 1.6 yeast BG. Our results show that canine phagocytes cultured in presence of 1.3, 1.6 yeast BG display a greater cytokines production of tumor necrosis factor (TNF)α and interleukin (IL)-12. Those data are really encouraging as IL12 is essential to initiate T cell responses against pathogens. These benefits against pathogens have shown reduced incidences of infections, subsequently reducing the reliance on antibiotics and enhancing sustainability. Several examples will be given on species close to dogs. Taking these results all together, the inclusion of 1.3, 1.6 yeast BG in pet diets or supplements offer a promising avenue for enhancing their health. Their multifaceted benefits, including immunomodulation or inflammatory control, make them valuable purified actives in the pet care industry.
34 The influence and interaction of nutrition with the immune system in companion animal models
Authors: Bobeck Elizabeth A
Published: September 2024

Understanding the impacts of nutrients in a species-specific manner has both practical and academic benefits for improving animal health. Therefore, species-specific animal models and research reagents are crucial to understanding molecular and physiological pathways. However, limitations in repeatable, descriptive models, sample size, and the ethics of companion animal research result in often needing to make inferences from human, murine, and other related immunology and nutrition research models. Recent companion animal work has focused on the impact of key nutrients in animal diets, including fat-soluble vitamins D, and E, omega-3 polyunsaturated fatty acids (PUFA), overall amino acid and energy balance over the lifespan, minerals including zinc and selenium, and feed additives such as probiotics and beta glucans. The selected research model, samples able to be collected, and available reagents for sample analysis will impact potential outcomes and inferences made from the data, including both acute to chronic impacts. From a theoretical standpoint, the balance between nutrient supplementation and impact includes understanding nutrients and responses of a model system in both deficiency and therapeutic level settings. For example, when supplementing Vitamin D, Vitamin E, or omega-3 polyunsaturated fatty acids, inclusion above currently recommended levels may optimize immune function, such as pathogen clearance, improved vaccine titer responses, or reduce inflammation. For other nutrients associated with immunomodulation such as zinc, additional chronic pharmacological supplementation may inhibit certain aspects of immune function, much like a deficiency scenario. Overstimulation of the immune system through nutrient supplementation may also impact the necessary modulation and repair roles that immune cells such as macrophages play in wound healing and anti-inflammatory responses. Continued work in nutritional immunology will further enhance our understanding of the power of nutrition and diet to improve health in companion animals.
496 Effects of sodium metabisulfite (SMBS) and SMBS-containing lipid microparticles on the performance and intestinal barrier functions of weanling piglets challenged by deoxynivalenol-contaminated diets
Authors: Yu Changning , Xu Haoxiang , Zhao Xiaoya , Yin Fugui , Yu Hai , Gong Joshua , Yang Chengbo , Liu Song
Published: September 2024

This study aimed to investigate the effects of sodium metabisulfite (SMBS) and SMBS-containing hydrogenated palm oil (HS) microparticles on the growth performance and intestinal barrier functions of weanling piglets challenged by deoxynivalenol (DON)-contaminated diets. Four corn-soybean-meal based diets were used: 1) negative control (NC, 0.00 mg/kg of DON); 2) positive control (PC, 3.3 mg/kg of DON); 3) SMBS (PST, 3.3 mg/kg of DON and 0.2% of SMBS); and 4) HS microparticles (HST, 3.3 mg/kg of DON and 0.45% of HS microparticles). Weaned piglets (n = 40) with similar body weights (BW; 8.22 ± 0.39 kg, 10 pigs/treatment) were fed for 28 d, including a 1-wk adjustment and 3 wk for exposure. Piglets subjected to the PC diet exhibited a noteworthy reduction in final BW by 13.3%, average daily gain (ADG) by 21.4%, and average daily feed intake (ADFI) by 20.1% compared with those on the NC diet (P < 0.05). Compared with the PC diet, the PST and HST diets increased by 6.76% and 4.31% in final BW (P < 0.05), 13.6% and 8.60% in ADG (P < 0.05), and 9.15% and 9.71% in ADFI (P < 0.05), respectively. No significant differences were detected in these values between the NC, PST, and HST diets (P > 0.05). There were no significant variations observed in the feed conversion ratio (FCR) among the four dietary treatments (P > 0.05). Feeding the PC diet to piglets led to a significant increase in the fecal score compared with the NC and HST diets (P < 0.05). No significant differences were detected in the mRNA expression levels of nutrient transporters and tight junction proteins among these four diets (P > 0.05). Additionally, compared with the NC diet, the PC diet significantly increased the mRNA abundance of Interleukin (IL)-6, IL-8, tumor necrosis factor (TNF)-α, and toll-like receptor 4 (TLR4; P < 0.05); however, a decreased mRNA abundance of IL-8 and TNF-α was observed in the pigs fed the HST diet (P < 0.05), indicating that the encapsulated SMBS from the HS microparticles could have the potential to mitigate the effects of DON. Overall, adding 0.45% of HS microparticles to a 3.3 mg/kg DON-contaminated diet in piglets could maintain the growth performance, and using the HS microparticles revealed some potential in DON detoxification by reducing the gene expressions of pro-inflammatory cytokines.
498 Feeding hydroxychloride or organic sources of zinc, copper, and manganese to broiler breeders on growth performance of offsprings when fed hydroxychloride or inorganic sources of the same minerals
Authors: Bakhshalinejad Reza , Torrey Stephanie , Kiarie Elijah
Published: September 2024

The study investigated the effect of feeding different sources of trace minerals (TM) such as zinc (Zn), copper (Cu), and manganese (Mn) in broiler breeders (BB) and their offspring on the growth performance of offspring. Ross 708 BB were housed in 24 pens (17 ♀ and 2 ♂) and allocated to two diets (12 replicate pen/diet): 1) HO, a blend of 80% hydroxychloride (HC) and 20% organic (OR) sources, and 2) OR, 100% OR sources (Table 1-4). Hatching eggs were collected from BB pens at 46, 54 and 62 wk of age, and incubated. Upon hatching, chicks were sexed, weighed, and placed in 24 sex-segregated pens (40 birds/pen), maintaining BB diet identification. One-half of chicks from BB fed HO or OR were fed HC and the other one-half were fed inorganic (InO) sources of Zn, Cu and Mn, effectively creating 4 treatments for offspring phase (n = 6; 3 pens per sex). Body weight (BW), average daily feed intake (ADFI), average daily gain (ADG), and feed conversion ratio (FCR) were calculated. Results showed that parental diets did not significantly affect chicken BW, ADFI, ADG, or FCR. However, parental age had significant effects (Tables 5-8). Offspring from 46-wk BB had greater BW on d 10, 21, and 42, increased ADFI on all diets, greater ADG on starter and grower diets, and improved FCR on starter and grower diets. Chicks fed HC diets displayed greater BW, ADFI, and ADG in certain phases. Overall, the study highlights the importance of TM sources and parental age in influencing broiler performance.
479 Pain control for the castration of newborn bull calves by elastration
Authors: Crevier Mariah , Haley Derek B , Rau Jeffrey , Gordon Jessica
Published: September 2024

All methods of castration are known to cause pain regardless of the method, or age of the animal. Our objective was to explore providing pain control for bull calves castrated by elastration prior to 1 wk of age. Singleton, bull calves (n = 85) born at the Ontario Beef Research Centre were enrolled and randomly assigned to 1 of 5 treatment groups at birth: a single dose of oral meloxicam at castration (1ORAL), a dose of oral meloxicam at castration and a second oral dose 1 wk later (2ORAL), a dose of injectable meloxicam at castration (1INJECT), not castrated (SHAM), or castrated without pain control (PAINFUL). Calves were treated within 48 h of birth and followed until weaning. All calves were observed 2 h/d for 13 different pain-associated behaviors (e.g., tail flicks, kicking, licking the scrotum) on the day of castration (d 0), as well as d 1, 2, 7, 8, and 9. To record general activity, from d -1 to d 14 each calf wore an Onset HOBO Pendant G Data Logger attached to one of their hind legs. Calves were weighed weekly until they were turned-out to pasture and thereafter weighed bi-weekly until weaning. Five behaviors were statistically significant between treatment groups. PAINFUL calves had roughly three times the rate of licking (P > 0.05) compared with calves in 1ORAL, 2ORAL, and 1INJECT groups, and four times the rate of licking compared with SHAM calves. Additionally, PAINFUL calves had two times the rate of tail flicks (P < 0.05) compared with meloxicam-treated calves, and five times the rate of tail flicks compared with SHAM calves. A treatment effect (P < 0.05) was observed for standing time, with PAINFUL calves spending the least amount of time standing on average in a 24-h period. No statistical time differences were seen between the remaining treatment groups. No treatment or treatment*time interaction effects were observed for lying time. A tendency was seen for treatment effect on lying time (P = 0.0581), with PAINFUL calves spending the most time lying on average and having a significance difference compared with all other treatment groups (LSM > 0.05). No treatment effect was seen for average daily gain up to wk 8, and for final weaning weights. Weight at time of castration was significant (P < 0.05); however, calves were not blocked by BW when assigned to treatment. In conclusion, meloxicam-treated calves expressed decreased rates of pain-associated behaviors compared with PAINFUL calves, and BW did not differ at time of weaning. Our results provide evidence that calves castrated by elastration before 1 wk of age and received meloxicam, experience less pain.
435 Use of plant bioactives to improve the efficiency of rumen function
Authors: Durunna Obioha N , Gonzalez Emmanuel , Gzyl Katherine E , Oyedeji Oluwatobi , Cheang Iris , Kommadath Arun , Block Hushton , McAllister Tim A , Fong Leonard , Lardner H (Bart) A , Holman Devin B
Published: September 2024

Plant bioactives, also known as phytogenics or phytobiotics, are secondary metabolites of plant origin that are deployed as host-defense mechanisms against predators or to enable them to be more competitive in their environment. These metabolites also regulate growth and reproductive functions in the plant. They can be grouped into three major classes: terpenoids, phenolic compounds, and alkaloids. Various studies have shown their worth in improving livestock production and health via insectifugal, organoleptic and enhanced rumen functions. Ruminants are critical to food security because they are able to convert poor-quality feed materials into nutritious products like meat. The rumen provides temporary storage of feed but serves the main function of digesting those complex materials through symbiotic relationships among prokaryotic and eukaryotic organisms within the rumen vat. Antimicrobial resistance and other health or social license challenges have led researchers to find acceptable replacements that will not exacerbate the health and social issues in animals and humans. Plant bioactives appeal to producers because of the ‘natural’ brand and because they are usually certified as generally recognized as safe (GRAS). Anecdotal reports from input companies show an increased demand for mineral supplements infused with phytogenics. The complex chemical compositions of these products appear to make them less prone to developing resistance by microorganisms. Phytogenics research has been further catalyzed by government legislation that has banned the use of medically important antibiotics to prevent the spread of antibiotic resistance. Potential improvements in livestock productivity are associated with mechanisms such as enhanced nutrient utilization, increased digestibility, modified digestive secretions or altered microbial communities. These benefits contribute to the increasing use of these phytogenics by livestock producers to keep their animals healthy and productive while enhancing the profitability of their operations. We will examine the different bioactives and their applications in improving the efficiency of the rumen function. Some commercial products in the Canadian market will be presented. Other research trials showcasing their potential benefits to rumen health and general animal productivity will also be discussed.
432 Genomic strategies to improve the efficiency of rumen function
Authors: Guan Leluo
Published: September 2024

The rumen harbors a complex symbiotic microbiome (bacteria, archaea, protozoa, fungi and viruses), which degrades plant cell walls and ferments sugars to the volatile fatty acids that provide energy to host. Extensive recent research has revealed that variation in rumen microbiome composition and function can directly and in directly influence many phenotypes in cattle such as feed efficiency, methane emission, metabolic health, milk and meat quality. Such findings highlight the opportunity to intervene rumen microbiome for improved productivity, health and reduced environmental footprint. More and more evidence revealed the individualized rumen microbiome and host genetics could be one of the factors in colonizing of selective rumen microbiome. This presentation will focus on to date knowledge on “heritability” of rumen microbes and explore the opportunities to breed cattle with a desired rumen microbiome for improved feed efficiency and lower emission of greenhouse gases.
222 Validation of Brix for predicting sugar concentration of alfalfa and orchardgrass
Authors: Soder Kathy J , Billman Eric D , Horst Jeff , Hafla Aimee , Balk Kristi
Published: September 2024

The objective of this study was to evaluate the accuracy of Brix in predicting sugar concentrations in fresh alfalfa (Medicago sativa L.; ALF) and orchardgrass (Dactylis glomerata L.; OG) forages to be used as an inexpensive and rapid field-level assessment of relative energy in forages. In a 2-yr study, fresh forages samples from ALF and OG monoculture pastures in central Pennsylvania, U.S. were collected once monthly from May to September. Samples were immediately evaluated for Brix values with a hand-held digital refractometer, and the remaining biomass was frozen immediately with liquid N to halt cellular respiration. Samples were lyophilized and analyzed for individual sugars and wet chemistry nutritive analyses. Brix values were correlated with wet chemistry analyses using the PROC CORR procedure in SAS, with significance established at P < 0.05. Brix was positively correlated (P < 0.05) with total and individual sugars in ALF during late spring and late summer (0.49 to 0.93), but correlations were non-existent (P > 0.05) or negative (-0.55 to -0.73; P < 0.05) in mid-summer. Brix values had moderate to strong negative correlations (P < 0.05) to NDF and ADF in ALF (-0.57 to -0.71). Conversely, Brix values did not correlate (P > 0.05) to any notable sugar parameters in OG beyond the first sampling date (0.60 to 0.74; P < 0.05). Brix was not correlated (P > 0.05) to NDF and ADF in OG. In summary, Brix values did not consistently predict sugar concentrations in fresh ALF and OG forages. Because Brix measures dissolved solids in solution (not just sugars), Brix readings collected from crushed ALF or OG samples may be confounded by fibrous fractions found in the solution as well as decreased sugar concentrations compared with fruit crops. Brix accuracy may also be dependent on seasonal temperature patterns, plant growth stage, and daily weather patterns. Other solutions should be investigated that rapidly assess sugar profiles and nutritive values of fresh forages.
280 AntagomiR-22-3p Injection alters miRNA expression and muscle fiber type of intrauterine growth restricted lambs
Authors: Duckett Susan K , Greene Maslyn A , Udoka-Johnson Aliute N S , Worley Grayson , Klotz James L
Published: September 2024

microRNAs (miRNA) are small non-coding RNAs that modulate muscle satellite cell proliferation. Previous research identified miR-22-3p as differentially expressed during ovine muscle development and in vitro experiments showed that antagomir-22-3p treatment enhanced satellite cell proliferation. The objective of this study was to test in vivo vascular injection of antagomir-22-3p in lateral saphenous vein on miRNA and HDAC family mRNA expression in intrauterine growth restricted lambs. Pregnant ewes (n = 18) with twins were either fed at 100% of NRC (CON) or nutrient restricted (60% NRC; NR) from gestational d 85 to parturition. On d 12 of age, NR lambs (n = 8) were randomly selected and given a systemic injection of antagomir-22-3p in the lateral saphenous vein of the right leg (MIR-NR). CON lambs (n = 8) were also randomly selected and given a sham injection of PBS in the lateral saphenous vein of the right leg (SHAM-CON). Antagomir-22-3p was reconstituted in phosphate buffered saline (PBS). Injections were given for 3 consecutive days and lambs harvested 24 d later. Blood samples were collected from each lamb weekly to monitor miR-22-3p expression. Lambs were slaughtered 24 d after the first injection and muscle mass measured. Muscle samples were removed for miR-22-3p and mRNA expression of potential targets. Cell-free circulating RNA was isolated from blood samples and miR-22-3p expression examined over time. Cell-free circulating miR-22-3p expression was downregulated (P < 0.05) for MIR-NR compared with SHAM-CON on d 14 after injection. On d 21 after injection, miR-22-3p expression in plasma tended (P = 0.08) to be down-regulated in MIR-NR compared with SHAM-CON. Lamb body weight and muscle weights at harvest were similar between MIR-NR and SHAM-CON treatments. In heart and semimembranosus (SM) muscles, expression of miR-22-3p was down-regulated (P < 0.05) in MIR-NR compared with SHAM-CON. In the gastrocnemius and semitendinosus muscle, miR-22-3p expression was unchanged (P > 0.05). The number of type I and IIa muscle fibers were greater (P < 0.05) for MIR-NR than SHAM-CON. Muscle fiber area of Type I, IIa or IIx fibers did not differ (P > 0.05) by treatment. The number of type IIx fibers did not differ (P > 0.05) between treatments. MIR-NR treatment appears to shift muscle fibers towards more oxidative metabolism and down-regulate HDAC-1, 3, and 11 and SIRT6 in SM. The systemic injection of antagomir-22-3P down-regulated miR-22-3p expression in circulation and in muscle tissues, which altered expression of HDAC/SIRT genes involved in muscle fiber type conversion and hypertrophy.
58 Awardee Talk: A decade of discovery in horse pasture utilization
Authors: Martinson Krishona
Published: September 2024

Perennial cool-season grasses are the foundation of horse pastures in the North Central U.S. A majority of U.S. horses graze pastures as a way to encourage exercise and socialization, and to reduce feeding costs. However, other forages must be evaluated to help extend the grazing season and respond to emerging issues (e.g., floods and winter kill). This abstract summarizes the results of six individual grazing trials that aimed to evaluate forage yield, horse preference, forage nutritive value, and horse health parameters of perennial cool season grasses and alternative forages. Over 10 yr, multiple adult horses in good health grazed monocultures of perennial cool season grasses, annual cool season grasses, legumes, annual warm season grasses, and cover crops in replicated small plots designed in a randomized complete block. Yield was mechanically harvested, samples for forage nutritive value were hand harvested, and preference was visually assessed. Horses were allowed to rotationally graze forages using best management practices throughout multiple Minnesota growing seasons (May through October). Blood glucose and insulin concentrations were collected to determine the impact of certain forage species on horse health parameters. Data were analyzed using various procedures in SAS with P values ≤ 0.05. Forage yields varied greatly between forage types (P ≤ 0.05) and ranged from 13 to 2 Mgּ ha-1. Many forages that were higher yielding, were among the least preferred by horses, including orchardgrass, oat, alfalfa, sudangrass, radish, and turnip. The most preferred forages included Kentucky bluegrass, timothy, meadow fescue, annual ryegrass, winter wheat, red clover, white clover, teff, and berseem clover (P ≤ 0.05). Almost all forages had greater forage nutritive values that met or exceeded the nutritional needs of horses in maintenance. Many warm season grasses had inverted calcium to phosphorus ratios and increased nitrate-nitrogen content. While no consistent relationship was found, horse preference tended to be positively associated with crude protein and nonstructural carbohydrates. When evaluating health parameters, horses grazing teff, an annual warm season grass, had reduced average glucose, average insulin, and peak insulin compared with horses grazing perennial cool season grasses in the late fall (P ≤ 0.05). Collectively, these results suggest that strategic use of pasture forages can be used to help manage common horse health concerns (e.g., obesity and Equine Metabolic Syndrome). While perennial cool-season grasses will remain the foundation of horse pastures in the North Central U.S., this research identified other suitable forage alternatives. Placing a priority on the balance of forage yield and horse preference, annual ryegrass, alfalfa, teff, and berseem clover can be used as horse pasture forage alternatives to extend the grazing season, maximize yield, increase pasture nutritive value, help manage common horse health concerns, and when responding to emerging issues.
147 The ‘horse-side’ of host-microbe interactions and gastrointestinal homeostasis in the equine hindgut
Authors: Coleman Stephen J , Moss Cameron , Wilson Amber , Reed Kailee , Jennings Kaysie , Kunz Isabelle
Published: September 2024

Homeostasis is a complex physiological process that enables biological systems to maintain balanced internal environments in response to internal and external stimuli. In the equine gastrointestinal (GI) tract, homeostasis involves a network of factors that regulate gene expression, maintain the integrity of the mucosal barrier, and modulate immune responses to pathogenic microorganisms while supporting commensal bacteria that provide benefits to the host (Figure 1). These factors work together and respond to changes in diet, environment, external stress, and challenges by infectious agents or toxins. Proper gastrointestinal function is dependent on maintaining homeostasis in the system, and the dynamic interactions between the microbial population (the microbiota) and the equine host are central to this equilibrium. The regulation and interplay between the equine host and GI microbiota are evident in the distribution of distinct microbial communities within the various compartments of the equine hindgut. The contributions of each compartment to digestive physiology and the overlap with various stages of microbial fermentation in the equine hindgut are well-researched. What remains to be documented is gene expression in tissues of the equine GI and the underlying role this might play in the processes of digestion, physiology, and homeostasis in the GI. To better understand the roles that host gene expression plays in the interactions with the microbiota, it is critical that we investigate gene expression in the different tissues along the intestinal tract. Protein-coding genes are crucial in maintaining the health of the gastrointestinal tract. They direct the synthesis of various structural elements, molecular transporters, and digestive enzymes, which support digestion, nutrient absorption, and gut integrity. Non-coding genes also play an important role in regulating protein-coding gene expression, modulating immune responses, and maintaining gut barrier function. Moreover, there is evidence that non-coding transcripts regulate the composition of microbial communities in the GI tract. The presentation will focus on the current research and future directions for investigating protein-coding and non-coding gene expression to understand the mechanisms involved in the host-microbe interaction in the equine hindgut and their potential role in maintaining GI homeostasis.
77 Differences in carcass quality and meat quality between cattle of different breed types
Authors: Roholt Bryce W , Crump Zachary C , Stafford Chandler , Okamoto Lillian , Alberto Anthony F , Spurling Ryan A , Matarneh Sulaiman , Thornton-Kurth Kara J
Published: September 2024

Crossbreeding cattle in the beef industry is a common practice to improve production and increase profitability. Introducing Bos indicus (BI) genetics into cattle herds is one potential method to improve production, as they are able to withstand higher temperatures, are better adapted to nutritional stress, and consume less water than Bos taurus (BT) cattle. However, introduction of BI genetics is known to decrease both carcass and meat quality compared with those from BT cattle. As such, the objective of this study was to determine how crossbreeding commercial Angus cows with Santa Gertrudis bulls to incorporate BI genetics impacts carcass and meat quality of the resultant offspring. This study utilized 38 steers of two different breeds: Angus (AN; n = 29; 100% BT) or Santa Gertrudis influenced (SG; n = 9; 19% BI, 81% BT). All steers were fed the same typical ration and harvested at a commercial facility once industry average body weight and backfat standards were met. Hot carcass weight (HCW), ribeye area (REA), yield grade (YG), and marbling scores were collected at harvest. Individual loins were collected for meat quality analysis. Meat quality data were collected after 14 d of wet aging at 4˚C. Meat color data was collected on d 0, 3, and 7. Statistical analysis was done using the MIXED procedure of SAS to assess the main effect of breed. Color analysis was conducted with day as a repeated measure. Least squares means were separated using Tukey-Kramer adjustments. Angus cattle had an increased (P = 0.009) REA and tended to have a reduced (P = 0.06) YG than SG cattle. However, no differences (P ≥ 0.13) between breeds were observed in HCW or marbling score. Additionally, no differences (P ≥ 0.08) were observed in meat quality (pH, drip loss, cook loss, Warner-Bratzler Shear Force, or Texture Profile Analysis) between breeds. There was not a day x breed (P > 0.65) or breed (P ≥ 0.57) effect for L*, a*, or b* color values. Day affected (P = 0.008) L*, a*, and b*, such that a* and b* both increased on d 3, then decreased on d 7, while L* increased on d 3 and remained consistent until d 7. These results are promising as they indicate there may not be differences in carcass quality and meat quality when utilizing this method to introduce BI genetics into a traditional BT production system. As such, this could be a useful tool in managing production systems in our beef herds. However, future research with a larger sample size will be necessary to gain more conclusive results.
78 Prolonged heat stress impact on molecular responses of skeletal muscle and growth performance in finishing beef steers
Authors: Eckhardt Erika P , Kim Jongkyoo
Published: September 2024

Rising temperatures significantly impact cattle production economically, reducing feed intake, efficiency, and growth, leading to substantial losses. Despite these known effects, there remains a paucity of data on the specific responses of skeletal muscle and adipose tissue to heat stress conditions. Therefore, this study aimed to elucidate the effects of prolonged heat stress on the molecular mechanisms of skeletal muscle growth and adipose tissue deposition and physiological response. Thirty-two predominantly Angus beef steers [initial average body weight (BW) = 364 ± 4.60 kg] were subject to a 28-d heat stress period. Steers were randomly allotted to one of two treatment groups (n = 16 steers/treatment) 1) Control (CON), exposed to outdoor environmental temperature-humidity index (THI) of 60; or 2) Heat Stress (HS), subject to THI of 70 to 80 for 8 h then returned to control treatment THI to simulate typical cooldown periods exhibited in instances of HS. Feed intakes were recorded daily, while BW was measured weekly prior to feed delivery. Biopsies of the skeletal muscle from the Longissimus muscle (LM) at the area of the 13th rib and adipose tissue from the subcutaneous fat of the flank region were performed on d 1, 14, and 28 for each individual steer and used for molecular analysis. For gene expression, a repeated measures ANOVA was utilized, acknowledging the individual animal as the experimental unit. The analysis of both gene expression over time and growth performance indicators was conducted using repeated measures ANOVA, with post-hoc analysis via Tukey’s test for specific comparisons. Data presentation includes the standard error of means, with an alpha (α) level set at 0.05 for determining statistical significance. Behavioral signs of heat stress, elevated respiratory rates, were observed with HS steers exhibiting a respiratory rate of 92.92 ± 24.79 breaths per minute (bpm) compared with 60.48 ± 14.94 bpm in CON steers (P < 0.01). Heat stress decreased average daily gain (ADG) during d 0 to 7 (49.11%) and d 15 to 21 (59.14%) compared with the control group (P < 0.01). Dry Matter Intake (DMI; P > 0.1) and feed efficiency (P > 0.1) were not altered in CON vs. HS steers. In skeletal muscle, on d 28 of exposure to heat stress, there was a significant overexpression of Heat Shock Protein (HSP) isoforms 20, 27, and 90 (P < 0.05) relative to the control group, accompanied by increased Myf5 (P < 0.05) gene expression. In adipose tissue, there was upregulation of PPARγ and SCD (P < 0.05), both of which are implicated with adipose tissue differentiation and lipid deposition process. Our findings indicated that HS modifies the expression of genes associated with skeletal muscle growth and adipose tissue deposition, concurrently impairing overall animal growth predominantly through reduced feed intake.
242 Awardee Talk: Dietary supplementation of blends of organic acids and monoglycerides alleviated diarrhea and systemic inflammation of weaned pigs experimentally infected with enterotoxigenic Escherichia coli F18
Authors: Park Sangwoo , Chen YIng , Wolfenden Ross , Liu Yanhong
Published: September 2024

This study aimed to investigate the effects of dietary supplementation of organic acids, monoglycerides, and combination of both on growth performance, diarrhea, and immune responses of weaned pigs experimentally infected with a pathogenic Escherichia coli (E. coli) F18. Pigs (n = 40; body weight = 7.81 ± 0.84 kg) were individually housed and randomly assigned to one of four treatment groups (10 replicates/treatment): basal diet (control), basal diet supplemented with organic acids blend (formic acid, lactic acid, and sodium formate) at 0.3%, monoglycerides blend at 0.3%, or combination of both the organic acids blend at 0.2% and the monoglycerides blend at 0.2%. The experiment lasted 28 d, with 7 d before and 21 d after the first inoculation (d 0). All pigs were orally inoculated with E. coli F18 (1010 CFU/3 mL) for 3 consecutive days from d 0. Growth performance was measured weekly and daily fecal score was recorded throughout the experiment. Fecal samples were collected on d 0, 2, 5, 7, 10, 14, and 21 post-inoculation (PI) to confirm the presence of β-hemolytic coliforms in the feces. Whole blood samples were collected on d 0, 5, and 14 PI to perform complete blood count analysis. Porcine Cytokine/Chemokine13-Plex Discovery Assay (Eve Technology, Canada) was also conducted with serum samples from d 0, 5, and 14 PI. All data were analyzed by ANOVA using the PROC MIXED of SAS with a pig as the experimental unit. The frequency of diarrhea was calculated and analyzed by Chi-square test. Supplementation of organic acids, monoglycerides, or the combination of both significantly reduced (P < 0.05) the frequency of diarrhea (25.5 to 29.8%) compared with control (39.3%). E. coli F18 infection increased (P < 0.05) counts of total white blood cells, neutrophils, and lymphocytes on d 5 and 14 PI, compared with d 0. Supplementation of the combination of organic acids and monoglycerides reduced (P < 0.05) the counts of total white blood cells, lymphocytes, and the ratio of neutrophils to lymphocytes, and tended (P < 0.10) to reduce neutrophil count on d 5 PI, compared with control. Pigs fed with monoglycerides had greater (P < 0.05) neutrophil counts than pigs in the control group on d 14 PI. Pigs fed with monoglycerides tended (P < 0.10) to have decreased serum granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-1 alpha (IL-1α), and tumor necrosis factor (TNF) -alpha concentrations on d 0, 5, or 14 PI compared with control. However, supplementation of organic acids, monoglycerides, or the combination of both had limited impacts on growth performance throughout the experiment. In conclusion, dietary supplementation of organic acids, monoglycerides, and the combination of both may alleviate diarrhea or systemic inflammation of weaned pigs during E. coli F18 infection by modulating related cytokines.