bluuebunny/crossref_metadata_2025 huggingface dataset:
236 Assessment of Early-Stage Thermal Manipulation on Broiler Chicken Muscle Satellite Cell Populations at Transfer and Hatch
Authors: Rogers John W , Hutson Brittany , Rueda Martha , Davis Jeremiah D , Purswell Joseph , Starkey Charles , Starkey Jessica D
Published: November 2023

Multi-stage hatching egg incubators are challenging to manage but still common throughout the US broiler industry. It is difficult to satisfy all embryonic temperature requirements in systems where late-stage embryos must be kept from overheating while ensuring early-stage embryos are not at sub-optimal temperatures. Our previous work showed improvements in performance and meat yield when incubation temperature was increased to 38.6 °C from embryonic day (ED) 4 to 11 as opposed to lowering it to 36.4 °C compared with a 37.5 °C control. The objective of this work was to assess the effect of thermal variation (TV) during early-stage incubation (ESI) on muscle satellite cell (SC) heterogeneity in broiler chicks at transfer and hatch to explore the mechanism responsible for increased meat yield in our previous study. Broiler breeder eggs (n = 2,160) were incubated at 37.5 °C from embryonic day (ED) 0 to 3. On ED 4, COLD incubator set points decreased to 36.4 °C, HOT incubator set points increased to 38.6 °C, and control incubators remained 37.5 °C (n = 2 incubators per treatment). On ED 11, all incubators were set to 37.5 °C until ED 18 when eggs were transferred to hatchers. At transfer (ED 18) and hatch (ED 21), pectoralis major (PM) and biceps femoris (BF) muscle samples were collected from 6 chicks per treatment. Samples were immunofluorescence stained to facilitate taxonomy of SC populations expressing the myogenic regulatory factors and SC markers, MyoD, MRF4, and Myf5, by fluorescence microscopy. Data were analyzed as a 1-way ANOVA with the GLIMMIX procedure of SAS. Means were separated at P ≤ 0.05 with the PDIFF option. Tendencies were declared when 0.0501 ≤ P ≤ 0.10. Chicks from COLD incubators had the greatest density of MyoD+:Myf5+ SC in their BF (P = 0.0261) and tended to have a greater density of MyoD+:MRF4+ SC in their PM muscle (P = 0.0562) compared with chicks from HOT incubators. On ED 21, chicks from HOT incubators had the greatest density of MyoD+:MRF4+:Myf5+ SC in their PM muscle (P = 0.0406). Temperature gradients as small as 1.1 °C during ESI altered BF SC populations in chicks at transfer and PM SC populations at both transfer and hatch. Overall, these results indicate that TV during ESI can influence SC population kinetics in both PM and BF muscles of modern, fast-growing, high-yielding broiler chicks at ED 18 and 21. Further investigation is needed to understand the longer-term effects on SC populations and the cell signaling pathways involved over time during the post-hatch grow out period to explain the meat yield responses observed in our previous work.
414 Awardee Talk: Current Status and Future Opportunities for Fresh Pork Quality
Authors: Dilger Anna
Published: November 2023

Pork is often viewed as a “middle-of-the-road” option. It is typically less expensive than beef, but more expensive than chicken. While beef cuts, especially steaks, are viewed as luxury items or high-end dining experiences, pork is more of a staple food featured as a variety of fresh and processed products at breakfast, lunch, and dinner. To increase demand for pork and capture more of the high-end market, improving fresh pork loin quality has been a focus of the industry for many years. There is evidence that these efforts have been successful. Compared with pork of the past, fresh pork loins have increased pH and darker color. Additionally, the incidence of tough pork has been reduced and overall pork tenderness improved. However, per capita consumption of pork by the consumers of the United States has not changed. This suggests that consumer acceptance and demand for fresh pork may not depend on intrinsic characteristics such as pH, color, and tenderness. Extrinsic factors like endpoint cooking temperature may have a larger influence on consumer acceptability of fresh pork loin chops. It is possible that, in terms of pork quality, we have been successful in eliminating the problems of the pork industry like pale, soft and exudative pork, but this is not sufficient to reach a consistently excellent eating experience in pork loins.
268 Copper Methionine Hydroxy Analogue Chelate in a Reduce and Replace Copper Strategy Improves Nutrient Availability in Growing Pigs
Authors: Lawrence Bradley V , Foran Chelsie K , Hintz Alex , Torres David , Acosta Camargo Jesus A , Provin Ashley
Published: November 2023

Research has shown that methionine hydroxy analogue chelated minerals [MHAC; MINTREX Trace Minerals (Novus International Inc., St. Charles, MO)] are more available than inorganic trace minerals. In growing pigs, 50 mg/kg of Cu as Cu-MHAC has been shown to reduce feed conversion compared with feeding 125 mg/kg Cu as CuSO4 and 150 mg/kg Cu as tri-basic copper chloride (TBCC). A metabolism study was conducted using 2 groups of 10 barrows (average BW of 33.2 + 3.03 kg) fed either 50 mg/kg Cu as Cu-MHAC or 150 mg/kg Cu as TBCC. There was a 14-d acclimation period followed by 3-d of total fecal and 5-d of total urine collection. Corn-soybean meal diets with 15% distillers dried grains and < 1% fat as soy oil were formulated to 0.98% SID lysine with 0.65% Ca and 0.49% P. Phytase was included at 1,500 FTU/kg. A common basal trace mineral premix supplying 120 mg/kg Zn, 10 mg/kg Cu and 20 mg/kg Mn in the SO4 form was used. Diets were provided in meal form twice daily at 5% of body weight per day. The total trial period was 21-d with BW measured at d 0 and 21. Feed disappearance was recorded throughout. Data were analyzed using the PROC MIXED procedure of SAS with treatment and initial BW as fixed effects and group as a random effect. Pigs fed Cu-MHAC gained 816 g/d compared with 787 g/d for those fed TBCC (P = 0.55). Feed conversion was 2.07 for TBCC pigs and 1.98 for Cu-MHAC pigs (P = 0.48). Dry matter digestibility was 90.9% and 89.9% (P = 0.18) for Cu-MHAC and TBCC pigs respectively. Dry matter fecal output was 9% less for Cu-MHAC pigs (P = 0.24). Cu retention percent was not different between Cu sources (64.4% Cu-MHAC vs 62.4% TBCC; P = 0.63). Cu excretion was less for Cu-MHAC pigs (41.3 mg/d Cu-MHAC vs. 103.9 mg/d TBCC; P < 0.001) as a result of reduced Cu intake. Cu-MHAC increased Zn (P < 0.05) and Mn (P < 0.01) retention by 8.9 and 11.1 percentage points, respectively. Iron absorption (P = 0.86) and retention (P = 0.81) were not affected by Cu source. Calcium absorption and retention were 3.8 percentage points greater (P = 0.12) for Cu-MHAC pigs. Absorption and retention of P was 3.4% (P = 0.25) and 2.7% greater (P = 0.49) for pigs fed Cu-MHAC. Cu-MHAC resulted in 1.9% greater N absorption (P = 0.06) and 8.7% greater N retention (P = 0.06%) than when 150 mg/kg Cu in the TBCC form was fed. These results indicate a reduce and replace Cu strategy with Cu-MHAC can reduce Cu excretion by 60% and improved overall mineral and N retention with the exception of Fe. These nutrient availability improvements may contribute to the improved feed conversion observed in performance trials with Cu-MHAC vs inorganic sources.
32 Feeding Gilts and Sows to Maximize Their Mammary Development
Authors: Farmer Chantal
Published: November 2023

The task of feeding growing replacement gilts, gestating gilts and sows to maximize their future milk yield is not easy. Yet, this is particularly important when considering the great demands made by the large litters of our current hyperprolific sow genetic lines. One aspect that needs to be considered is the effect of feeding on mammary development taking place before the onset of lactation, which is a major determinant of potential milk yield. One can only attempt to stimulate mammogenesis during periods with rapid mammary development. In swine, these periods are from three months of age until puberty, from 90 days of gestation until farrowing, and throughout lactation. Early studies showed that a 20% or 26% feed restriction from 90 days of age until puberty drastically reduces mammary parenchymal tissue mass. However, in a more recent study, sow milk yield was not altered following a 10% or 20% feed restriction, or a 25% dietary fiber addition (diluting dietary energy by 5%) from 90 days of age to breeding. This absence of effect may be due to the greater feed intake of control gilts in that recent study compared with the older studies. Such a difference in feed intake was likely brought about by genetic selection for faster growing pigs, and it appeared that feed intake of growing gilts can be reduced to 2.7 kg/day without detrimental effects on their future milk yield. During prepuberty, inclusion of the phytoestrogen genistein (2.3 g/day) in the diet increases the number of mammary parenchymal cells. During late gestation, feeding very high energy levels (10.5 Mcal ME/day) may have detrimental effects on mammary development and subsequent milk production. Furthermore, feed intake throughout gestation is important because of its effect on body condition. Gilts that are too thin (< 16 mm backfat thickness) in late gestation have reduced mammary development. A 40% increase in SID Lys via inclusion of additional soybean meal to the diet of gilts from days 90 to 110 of gestation increased mammary parenchymal mass by 44%. On the other hand, providing the same 40% increase in dietary SID Lys to multiparous sows during late gestation had no significant effect on mammary parenchymal mass. These findings therefore support the use of phase-feeding during gestation of gilts only. Increasing circulating concentrations of the growth factor IGF-1 during late gestation also increased mammary parenchymal mass by 22%. Current data clearly demonstrate that feeding management before lactation can be used to improve sow milk yield.
436 A Strategy for a Climate-Resilient Sustainable Feed System
Authors: Adamchick Julie
Published: November 2023

Implementing sustainable practices within the livestock and poultry feed industry and throughout the value chain is essential to reaching global climate targets. Explore what is defined as four critical components of a sustainable feed strategy: circularity, innovation, regenerative agriculture, and responsible sourcing for a climate-resilient global feed system.
290 Ewe Undernutrition Alters Cotyledon Development and Function
Authors: Welter Francesca , Marques Rodrigo S , Bradbery Amanda N , Posbergh Christian , McCoski Sarah
Published: November 2023

Undernutrition is common for animals maintained in a range setting, particularly during periods of drought, and during gestation can be detrimental to offspring development. The placenta is a known mediator for maternal-fetal nutrient exchange, and developmental impacts to the placenta during times of nutritional stress contribute to poor offspring outcomes. The objective of this study was to determine the impacts of maternal nutrient restriction on the development and function of placental cotyledons. Targhee ewes were allocated into two dietary treatment groups for the entirety of gestation. The control group (CON; n = 10) was fed to meet 100% of NRC requirements and the nutrient restricted group (NR; n = 11) was fed to meet 60% of NRC requirements, to mimic the nutritional stress experienced by range ewes during drought. At the time of lambing total placental weight, total cotyledon number, and lamb birth weight were recorded. Cotyledons (n = 3 / placenta) were removed from multiple locations, weighed, and processed for RNA-sequencing. Total placental weight, total cotyledon number, and lamb birth weight were not affected by maternal diet restriction (P > 0.05). Average cotyledon weight was greater in the CON group compared with the NR group (P < 0.05). Gene ontology (GO) and Kyoto encyclopedia of genes and genomes pathways (KEGG) analyses were performed to identify biological pathways involved in placental function and nutrient transfer. Cotyledons from NR singletons vs CON singletons expressed 470 differentially expressed genes (DEGs; P < 0.05; 187 up-regulated, 283 down-regulated). Gene ontology terms represented by DEGs include hormone activity (P = 0.0003) and antigen processing and presentation (P = 0.0004). KEGG pathways of interest include pyruvate metabolism, estrogen signaling, extracellular matrix receptor interaction, and antigen processing and presentation. There were also 426 DEGs (P < 0.05; 195 up-regulated, 231 down-regulated) in cotyledons of NR twins vs CON twins. Represented GO categories include heme binding (P = 0.003) and oxidoreductase activity (P = 0.03). These data show that prolonged nutrient restriction alters cotyledon development and gene expression indicating modifications in placental function. These changes in placental function likely mediate poor offspring developmental outcomes observed following gestational under nutrition.
28 Melanocortin 3 Receptor in Neural Circuits Linking Metabolic State with Reproduction and Growth
Authors: Bedenbaugh Michelle N , Sweet Serena , Mendoza-Romero Haley , Brener Samantha , Hawkins Sydney , Yu Gina , Zimmermann Jessie , Sweeney Patrick , Cone Roger , Simerly Richard
Published: November 2023

Metabolic state must be communicated to the brain to regulate behavior, growth, nutrient partitioning and development to meet energetic demands. While it is clearly evident that reproduction and energy balance are closely intertwined, the neural circuits integrating these two processes are poorly understood. Recent functional data suggests the melanocortin 3 receptor (MC3R) mediates the exchange of information between reproductive and metabolic state. Additionally, females exhibit uniquely aberrant metabolic and reproductive phenotypes after deletion of MC3R. In this work, we aimed to characterize the role of MC3R neural circuits in linking metabolic state with reproduction and growth in females. We found that MC3R is expressed in brain regions known to have a role in the control of reproductive and metabolic state, including the anteroventral periventricular nucleus (AVPV) and arcuate nucleus (ARH). In the ARH of female mice, significant differences in overall levels of Mc3r mRNA were not observed at postnatal day 16 (P16), P28 or P48, nor did the percentage of ARH Kiss1, Esr1, Sst, Pomc or Agrp neurons doubly-labeled for Mc3r appear to change during postnatal development. However, the percentage of ARH Ghrh neurons labeled for Mc3r significantly increased from P16 to P48. Thus, MC3R in the ARH may play a potential role in conveying metabolic signals critical for growth during development. In the AVPV of female mice, overall abundance of Mc3r mRNA was low at P16, but increased significantly by P28, and was further elevated in mature mice (P48). Additionally, the percentage of Kiss1- and Esr1-expressing neurons in the AVPV labeled for Mc3r increased significantly between P16 and P48, suggesting that Mc3r may have an important role in the timing of sexual maturation. In addition to the direct regulatory action of MC3R expressed in KISS1 neurons in the AVPV, the impact of MC3R signaling may also be transmitted transynaptically via direct neural projections from MC3R neurons to KISS1 neurons in the AVPV, or to GnRH neurons in the rostral preoptic area. Clearly labeled MC3R terminals were observed in close apposition to both KISS1 neurons in the AVPV, and GnRH neurons in the rostral medial preoptic area. Although both the GnRH and KISS1 neuronal populations appeared heavily innervated by MC3R neurons, the density of MC3R terminals onto KISS1 neurons appeared to be substantially greater than that onto GnRH neurons, suggesting that inputs to AVPV neurons may be particularly impactful on reproduction. Thus, MC3R may not only regulate the activity of KISS1 neurons in the AVPV directly, but may also function transynaptically as an important neurobiological substrate for coordination of metabolic state with sexual maturation and reproductive function.
312 Emissions Intensity of Growing Cattle with Contrasting Residual Methane Production, Average Daily Gain, Feed Conversion Ratio, Residual Feed Intake, and Feed Intake
Authors: Gonzalez Luciano A , Shirvan Milad Bagheri , Molfino Juan
Published: November 2023

Various options exist to produce beef from growing cattle with low environmental footprint normally linked to the genetic merit of animals for traits such as residual feed intake (RFI), residual methane production (RMP), residual CO2e production (RCeP), average daily gain (ADG), feed conversion ratio (FCR), and dry matter intake (DMI; % of BW). The ultimate environmental footprint can be measured through the intensity of methane emissions (IME) in g CH4/kg ADG or the intensity of CO2e (ICDE) adding up both CH4 and CO2 production in g CO2e/kg ADG. The objective of the present study was to compare the IME and ICDE of animals with low, medium, and high traits for RMP, RCDE, ADG, FCR, RFI, and DMI. Five cohorts of 77 steers composite steers and heifers (Angus, Charolais, and Shorthorn) were tested for RFI for 70 d using electronic feeders and CH4 and CO2 production measured using two GreenFeed units in the pens. Only animals with more than 25 visits longer than 3 min were used for the analysis and the final dataset contained 202 animals. Animals within each RFI test were divided into equal groups with low, medium, and high values for each variable RFI, RMP, ADG, FCR, and DMI. Data were averaged for each animal and trial, and analyzed using ANOVA with the fixed effects of group, trial, and their interaction. The IME were different for animals with contrasting RMP, ADG, and FCR (P < 0.05) but not between animals with contrasting DMI and RFI (P > 0.05). The largest difference on IME was found between animals with low and high RMP, ADG, and FCR, and least for RFI and DMI with values being 33.9, 28.1, 22.3, 6.2, and 1.5 g CH4/kg ADG, respectively (Table 1). Results were similar when emissions intensity were expressed as ICDE (Table 1), except animals with low RFI produced less ICDE compared with those with high FI (P = 0.02). Results indicate that the environmental footprint of growing cattle can be reduced with animals with low RMP and high ADG at similar extents, whereas RFI and DMI have lesser impact.
308 Effect of Thermal Variation During Late-Stage Incubation and Sex on Broiler Chicken Body Weight and Carcass Parts Uniformity
Authors: Banegas Jorge E , Hutson Brittany , Gregg Caroline R , Rueda Martha , Davis Jeremiah D , Purswell Joseph , Starkey Charles , Starkey Jessica D
Published: November 2023

Low uniformity of broiler live body weight, carcass, and parts weights can reduce overall processing yields and profitability. The objective of this study was to evaluate the effects of thermal manipulation (TM) during late-stage incubation (LSI) and sex on the uniformity and coefficient of variation (CV) in high yielding broilers. Yield Plus ′ Ross 708 broiler breeder eggs (n = 2,160) were incubated at 37.5 °C from embryonic day (ED) 0 to 10. From ED 11 to 18, eggs were incubated at 1 of 3 air temperature set points: 37.5 °C (CTL), 36.4 °C (COLD), or 38.6 °C (HOT; n = 2 incubators per treatment). On ED 18, all eggs were transferred to baskets in hatchers set to 36.7 °C. Chicks were vent sexed, placed in floor pens blocked by incubation treatment and sex (n = 6 replicate pens of 30 birds per treatment), and fed a common diet. Broilers were individually weighed at d 9, 23, and 32, then, the 15 birds from each pen closest to the pen median BW were processed on d 33. The distance of each bird BW from the pen mean and median, TM treatment, sex, and whole flock BW over time, uniformity of BW (within 10% of the mean), and intra-pen CV were calculated. Data were analyzed as a 2-way ANOVA using the GLIMMIX procedure of SAS ver. 9.4 with TM treatment and broiler sex serving as the main effects. Means were separated at P ≤ 0.05 with the PDIFF option. On d 9, a TM by sex interaction was observed, and the BW of female CTL chicks was less variable from the pen mean compared with broilers hatched from COLD and females from HOT incubators (P ≤ 0.026). On d 9, sub-optimal incubation temperatures (HOT and COLD) during LSI resulted in higher individual female bird BW variation from the pen mean and median (P = 0.013). Incubating chicks in COLD incubators during LSI increased d-9 individual bird BW distance from the treatment, sex, and flock mean and median BW compared with CTL and HOT (P ≤ 0.037). In addition, BW uniformity within a pen was less in broilers hatched from COLD incubators than both CTL and HOT on d 9 (P = 0.033) and tended to be less on d 32 (P = 0.099). The inverse was observed for CV (P ≤ 0.040). Broilers hatched from COLD and HOT incubators had greater CV for carcass (P = 0.049) and wing (P = 0.028) as well as drumstick (P = 0.079) weights. These results indicate that sub-optimal LSI conditions can negatively influence uniformity of broiler live BW, carcass and parts weights and highlights the importance of achieving optimal incubation conditions.
354 Effect of Finishing System on Growth, Efficiency, and Carcass Quality of Dairy × Beef Hybrids
Authors: Grote Ally J , Wommack Addie , Robison Colton A , Farran Garrett , Wilson Blake K , Beck Paul A , Genther Schroeder Olivia N , Wistuba Troy
Published: November 2023

Our objective was to determine how calf-fed or yearling finishing systems affect the performance and efficiency of dairy-beef crossbred steers. Dairy-beef hybrid steers were acquired from Land O’ Lakes Calf Milk Research Facility at Grey Summit, Missouri at 12-wk (BW /SD) of age and transported to Willard Sparks Beef Research Center (WSBRC). Upon arrival at WSBRC, steers were weighed, vaccinated, treated for parasites, and implanted with 36 mg of zeranol (Ralgro). Alternating groups of steers were placed either directly on finishing diets (FIN) or on high-quality pasture and supplementation for 5 to 6 mo before returning to WSBRC for finishing (GRW/FIN). Steers in FIN were grown on successively higher energy growing diets through d 112, stepping up to a 20% roughage growing diet from d 28 to 112. On d 112, FIN steers were transitioned to a 12% roughage finishing diet. A final 8% roughage finishing was fed to FIN steers from d 224 to slaughter. Steers in FIN were reimplanted with Ralgro on d 56, Component TE-IS (80 mg trenbolone acetate, 16 mg estradiol, and 29 mg tylosin tartrate; Elanco US, Greenfield, IN) on d 112, and Component TE-S (200 mg progesterone, 20 mg estradiol benzoate, 29 mg tylosin tartrate; Elanco) on d 224. Steers in GRW/FIN were returned to WSBRC, weighed, and processed when they reached 312 ± 7.0 kg. Steers in GRW/FIN were implanted with Component TE-IS at the start of finishing, and Component TE-S on d 120. Steers in GRW/FIN were stepped up to the finishing diet when they reached 407 ± 6.0 kg. Finishing diets for the final 28 d for FIN and GRW/FIN included ractopamine hydrochloride at a rate of 300 mg·steer-1·d-1. At WSBRC, steers within each finishing system were sorted by BW into 4 to 5 head pens. Initial and terminal BW were greater (P < 0.01) in steers in the GRW/FIN finishing system. Body weight at reimplant was greater (P < 0.01) for FIN. Steers in the GRW/FIN system were on feed for fewer (P < 0.01) days compared with FIN steers. Average daily gain (ADG) and DMI (kg·steer-1·d-1) were greater (P < 0.01) for GRW/FIN. Steers in GRW/FIN had a greater (P < 0.02) feed:gain ratio than those placed directly into a finishing system. There were no differences (P < 0.10) in USDA Yield Grade, marbling, ribeye area (REA), or back-fat thickness (BFT) between finishing systems. Steers in FIN had a greater (P < 0.01) dressing percentage (DP) and lighter (P < 0.01) hot carcass weight than those for GRW/FIN. Finishing system has an impact on performance and efficiency of dairy-beef hybrid steers, but minimal impact on carcass quality.
348 The Influence of Previous Nitrogen Levels on Nitrogen Metabolism and Rumen Gene Expression of Grain Or Forage-Fed Finished Steers
Authors: Silva Aghata , Franco Arturo Macias , Mazza Pedro , Brody Tio , Rockwell Macy , Ferguson Bradley S , Fonseca Mozart A
Published: November 2023

The objective of this study was to evaluate how the previous nitrogen levels (PNL) in the diet might affect nitrogen balance and nitrogen-related genes in the rumen of either forage-fed or grain-fed steers during finishing. Twenty-four crossbred Angus steers were randomly distributed into one of two backgrounding nutritional plans: moderate (MP; crude protein (CP): 9.10%) or high (HP; CP:12.6%). After 85 d, animals were blocked by PNL, transitioned, and fed a finishing diet for 105 d, which consisted of either alfalfa only (forage-fed; CP: 21.3%) or predominantly whole grain (grain-fed; CP: 10.8%). Feed, orts, feces, and urine samples were collected in both phases. By the end of the finishing phase, animals were slaughtered, and ventral sac rumen tissue was collected. Gene expression of Aquaporins (AQP) -3 and -7, and UT-B from rumen tissue were assayed via real-time qPCR; 18S rRNA was used as an endogenous control. Animals on MP diets excreted less N through urine (P < 0.01) and feces (P < 0.01), while retaining more N (P < 0.01), which resulted in an increased N efficiency (P < 0.01) compared with HP animals. No differences were observed for microbial N production (P > 0.05). Grain-fed animals consumed less N (P < 0.01), but still had a greater amount of N being digested compared with forage-fed animals (P < 0.01), as well as the least excretion of N through feces (P < 0.01) and urine (P < 0.01), and consequently a greater rate of N being retained (P < 0.01) and a greater efficiency on utilizing the ingested N (P < 0.05). Further, an interaction was also observed between treatment and PNL, where animals coming from a MP had the least dry matter intake, greatest amount of N being digested and least N excretion, fecal output, and excretion of N through the feces (P < 0.05) when finished on a grain-based diet. In the rumen, steers coming from a low PNL that were finished as forage-fed, had the greatest expression of AQP7, with no statistically significant differences observed for the other groups. When comparing only animals backgrounded on MP, AQP7 (P < 0.01) expression was greater in forage-fed animals, with a trend for greater expression of UT-B in grain-fed animals (P < 0.1). Overall, these results indicate that animals receiving MP will reduce their excretion of N while producing the same amount of microbial N due to more efficient N recycling. Further, carried-over effects were also observed after these animals were transitioned to grain-fed finishing systems. In the rumen, PNL affects expression of AQP7 and UT-B, which may ultimately impact nitrogen metabolism, since both genes are also related with urea transport.
344 Incorporation of Hemp Hulls and Screenings as Alternative Feed Sources for Ruminants
Authors: Terry Stephanie A , McAllister Tim A
Published: November 2023

Currently there are no legal markets for feeding hempseed hulls or screenings to ruminants in Canada. This represents a significant wastage of high-quality feed that could be utilized in ruminant production. Therefore, the objectives of this project were to 1) evaluate the in situ rumen digestibility of hemp hulls and screenings; 2) evaluate the effect of including hemp hulls and screenings on the growth performance of feedlot lambs, and 3) assess if there are cannabinoids within the carcasses of growing lambs, and the milk of lactating ewes. Three ruminally cannulated Angus × Hereford heifers were used to determine the in situ degradability of hemp hulls and screenings. Wheat screenings, hemp hulls, and hemp screenings were weighed into polyester bags and incubated in the rumen for 0, 2, 4, 8, 12, 24, 48, 96, 120, and 240 h. The kinetics of in situ DM disappearance were estimated using a non-linear regression procedure of SAS. Wheat screenings had a similar soluble fraction to hemp hulls and screenings; however, hemp screenings had a greater (P < 0.01) soluble fraction than hemp hulls. The rapidly degradable fraction, total potentially degradable fraction, and ruminal degradability were greatest (P < 0.01) for wheat screenings, followed by hemp screenings, and then hemp hulls. Study 2 was conducted using twelve Canadian Arcott x Suffolk ram lambs randomly allocated to one of three treatments: control (Wheat screenings), hemp hulls, and hemp screenings. By-products were included at 20% dietary dry matter, and lambs were fed ab libitum until they reached 50 kg. To test for cannabinoid residues, samples of muscle, adipose tissue, liver, and kidney were taken post-mortem. Study 3 was conducted using fifteen lactating Canadian Arcott x Suffolk ewes with twins, fed the same treatments as in Objective 2. Hulls and screenings were included at 15% DM, and ewes were fed dietary treatments for 30 d, with dry matter intake and body weight recorded weekly. On d 15 and 30, ewes were hand milked to obtain samples for cannabinoid analysis. This research will have an important role in supporting Canadian approval for feeding industrial hemp by-products to ruminant livestock.
343 Combination of Feed Additives to Reduce Methane Emissions and Increase Performance By Feedlot Cattle
Authors: de Carvalho Victor Valério , Souza William L L , Perdigão Alexandre , Niehues Maria B , de Matos Isabelle Errobidarte , Ribeiro Maryana M , Acedo Tiago S , Tamassia Luis , Walker Nicola , Kindermann Maik , Da Cardoso Abmael Silva , Reis Ricardo
Published: November 2023

Our objective was to evaluate the effects of 3-Nitrooxypropanol (3-NOP) associated with different feed additives on performance, carcass characteristics and enteric methane (CH4) emissions. Twenty-seven Nellore bulls (initial BW, 410 ± 6 kg) were randomly allocated to three treatments with nine replicates per treatment (animal as experimental unit). The animals were fed a high-concentrate feedlot diet (R:C, 10:90) for 102 days, according with the following three treatments: 1) Control (CTRL): Sodium Monensin (26 mg/kg DM); 2) BOV: Control + 3-NOP (Bovaer;100 mg/kg DM); 3) BOVPERF (Bovaer Performance pack): Control + 3-NOP (100 mg/kg DM) + Essential oils (Crina Ruminants, 100 mg/kg DM) + 25-OH-Vitamin D3 (Hy-D, 0.10 mg/kg DM) + carbo-amino-phospho-chelate of chromium and zinc (0.4 and 60 mg/kg of DM, respectively). The gases emissions (CH4 and H2) and DMI variables were assessed individually, by using the GreenFeed and Intergado electronic system placed in the feedlot pen, respectively. The BW of Yearling bulls were recorded at the beginning and final of the experiment after 16-h fasting (Table). Data were analyzed by ANOVA using the PROC MIXED of SAS 9.4, in which means comparison were evaluated by Tukey test at P < 0.05. Feeding BOVPERF increased DM intake during adaptation period (P = 0.04), and over the total period (P < 0.01) compared with control with no difference on feed efficiency (P =0.61). There was no difference (P > 0.05) on DMI between CTRL and BOV. Animals fed BOVPERF had greater HCW (+13 kg, P = 0.04) and greater carcass ADG (+120 g/d, P = 0.04) compared with CTRL. Animals fed BOV and BOVPERF emitted 39% less CH4 (P < 0.01) and produced 292% more H2 (P < 0.01) compared with CTRL. In addition, there were significant reductions in methane intensity, as measured by the ratios CH4/kg DM (-42%; P < 0.01), and CH4/kg carcass ADG (-41.13%; P < 0.01) for animals fed with BOV and BOVPERF compared with CTRL. We conclude that feeding Bovaer performance pack reduces methane emissions and increases carcass production in feedlot beef cattle.
358 The Effects of Varying Levels of Cotton Gin Byproduct and Wet brewers’ Grains on Growth Performance of Growing and Finishing Steers
Authors: Newsome Madeline , Poore Matt H , Harmon Deidre D , Shaeffer April D , Talbott Charlotte L , Fellner Vivek , Griffith Emily H
Published: November 2023

The abundance of craft breweries provides widespread availability of wet brewers grains (WBG) to be used by beef cattle producers as a potential feedstuff. Cotton gin byproduct (CGB) is a feedstuff typically reserved for mature beef cows due to its low and variable feed value. Both WBG and CGB have high cost of transportation but are sometimes used by producers near supply centers due to their low price. The objective of this study was to analyze animal performance of growing Angus steers fed total mixed rations with varying amounts of CGB and WBG. Sixty-four Angus steers (365 ± 26 kg) were allotted and blocked by initial body weight (BW) in a randomized complete block design to 8 dietary treatments and fed in 2 phases, growing phase (GP) and finishing phase (FP) (84-d and 69-d, respectively). Dietary treatments were arranged in a 2 x 4 factorial with two levels of CGB (0 or 25% of DM) and 4 levels of WBG (0, 10, 20 or 30% of DM). The control and base of all treatments were corn, corn silage and soybean meal. Body weights were recorded on two consecutive days at the beginning and end of GP and FP. Feed samples were collected, and refusals were weighed weekly. Data were analyzed using the MIXED procedure of SAS 9.4 with main effects of CGB, WBG, and the interaction. The linear, quadratic, and cubic effects of increasing levels of WBG and CGB were tested with polynomial contrasts. Average daily gain (ADG) did not differ among dietary treatments (0, 25% CGB and 0, 10, 20, 30% WBG) for GP, (1.67, 1.61, and 1.67, 1.57, 1.74, and 1.60 kg/d, respectively) (P > 0.3031), FP (1.53, 1.61 and 1.56, 1.53, 1.61, and 1.58 kg/d) or the overall trial (1.61, 1.62 and 1.62, 1.55, 1.68, and 1.60 kg/d). The addition of CGB increased GP dry matter intake (DMI; 11.06 vs 11.99 kg/d; P = 0.0011), while the addition of WBG linearly decreased GP DMI (11.81, 11.69. 11.81, and 10.81 kg/d; P = 0.0292). There was an interaction between CGB and WBG (P = 0.0206), with increasing levels of WBG at 0% CGB exhibiting a cubic effect (P = 0.0127), but no effect at 25% CGB. Inclusion of CGB decreased feed efficiency (FE) in the GP (6.77 vs. 7.69; P = 0.0008) but had no carry-over effect in the FP. There was no effect of WBG on FE in GP or FP. In conclusion, CGB increased DMI, reduced FE, and maintained ADG. Increasing quantities of WBG did not reduce ADG or FE, but decreased DMI with increasing feeding level. Therefore, WBG and CGB can be considered viable options for cattle producers seeking to lower input costs.
359 Investigation of Supplementation Rates for Extruded 100% Ddgs Cubes on Mixed Grass Prairie in Western Oklahoma
Authors: Grigsby Zane N , Worthington Charles , New Marty G , Beck Paul A
Published: November 2023

This experiment was conducted at the Marvin Klemme Research Station near Bessie, OK in the summers of 2021 and 2022 to test the effects of increased supplementation rates with extruded DDGS cubes on animal performance and supplemental efficiency of steers grazing mixed grass prairie in Western Oklahoma. Steers (n = 133 BW = 247 ± 24 kg and n = 96 BW = 264 ± 16 kg) in 2021 and 2022, respectively, were allocated to 3 supplementation treatments; 1) Negative Control (NC), ad lib free choice mineral only, 2) Low Supplement (LS), 0.91 kg of supplemental DDGS cubes animal-1·d-1, and 3) Medium Supplement (MS), 1.81 kg of supplemental DDGS cubes/animal/d. Pastures were stocked at 2.02 ha/steer in 2021 but the stocking density in 2022 was decreased to 2.83 ha/steer due to drought causing poor range condition and limited forage biomass availability. Data were analyzed as a randomized complete block design using PROC MIXED in SAS 9.4. In 2021, early season ADG of LS and MS were 0.43 and 0.58 ± 0.033 kg greater (P < 0.0001) than NC, respectively. Late season ADG was increased by 0.21 and 0.29 ± 0.033 kg (P < 0.0001) by LS and MS, respectively. Overall, ADG was 0.34 and 0.46 ± 0.29 kg greater (P < 0.0001) than NC for LS and MS, respectively. Supplemental efficiency in the early summer was 0.16 ± 0.03 kg of added gain/kg of supplement greater (P < 0.0001) for LS than MS. Late season efficiency was 0.07 ± 0.02 greater (P < 0.0001) for LS than MS. Season long supplemental efficiency was 0.12 ± 0.02 greater (P < 0.0001) for LS than MS. Gain per hectare was greatest for MS, 30.5 and 8.0 ± 1.92 kg greater (P ≤ 0.0003) than NC and LS, respectively. In 2022, early season ADG was increased by 0.2 ± 0.054 kg (P ≤ 0.0003) for both LS and MS. Late season ADG was 0.27 and 0.52 ± 0.043 kg greater (P < 0.0001) than NC for LS and MS, respectively, while overall ADG was 0.24 and 0.37 ± 0.04 kg greater (P < 0.0001) for LS and MS, respectively. Early season supplemental efficiency was 0.11 ± 0.04 greater (P ≤ 0.005) for LS than MS, late season efficiency did not differ (P ≥ 0.89). Overall efficiency was 0.05 ± 0.03 greater (P ≤ 0.05) for LS than MS. Gain per hectare of MS was 17.8 and 6.5 ± 1.92 kg greater (P ≤ 0.001) than NC and LS, respectively. These data suggest that increased supplementation rates with extruded DDGS cube is a viable option to increase performance of steers grazing mixed grass prairie, especially when forage quality is deficient in nutritive value or availability, but, in most cases the efficiency of the supplement decreases.
356 Dietary Fenugreek Seed Extract Improves Dry Matter Intake, Apparent Total Tract Nutrient Digestibility, and Alters Whole Blood Transcriptome of Holstein Dairy Heifers
Authors: Taiwo Godstime A , Sidney Taylor S , Idowu Modoluwamu , Eichie Francisca , Morenikeji Lanre , Ogunade Ibukun M
Published: November 2023

This study was conducted to evaluate the effects of dietary supplementation of a fenugreek seed extract (SAP) as a source of saponins on dry matter intake, blood metabolites, apparent total tract nutrient digestibility, and whole blood transcriptome of Holstein dairy heifers. Eight heifers (BW = 477 ± 23.8 kg) were stratified by BW and then randomly assigned to one of two treatments in a cross-over design with two 35-d experimental periods and a 14-d wash-out between the two periods. The heifers were housed individually in eight dry lot pens. Each pen was equipped with one GrowSafe intake node. Treatments were 1) corn silage-based diet with no additive (CON) and 2) corn silage-based diet plus 2 g ·animal-1·day-1 of SAP. Variables such as DMI and apparent total tract nutrient digestibility were analyzed as a randomized block design using the GLIMMIX model of SAS (SAS 9.4, SAS Inst. Inc., Cary, NC) using animal as the experimental unit. Blood metabolites that were measured repeatedly over time were analyzed using repeated measures and tested for the effect of treatment (CON vs. SAP), period, day of collection, and the day × treatment interaction. Dairy heifers fed supplemental SAP had greater (P ≤ 0.05). DMI and apparent total tract digestibility of dry matter, crude protein, and neutral detergent fiber compared with CON. Dairy heifers fed supplemental SAP had decreased (P = 0.03) blood urea nitrogen and greater (P = 0.01) blood glucose concentration compared with CON. Pathway analysis via gene set enrichment analysis revealed increased (FDR ≤ 0.05) transcript levels for gene sets belonging to ISG15 antiviral mechanism, metabolism of proteins, citric acid cycle and respiratory electron transport, ATP synthesis by chemiosmotic coupling, and complex I biogenesis in dairy heifers fed supplemental SAP compared with CON. Decreased (FDR ≤ 0.05) transcript levels for gene sets associated with erythrocytes take up/release carbon dioxide, release/take up oxygen, and O2/CO2 exchange in erythrocytes were also observed with SAP supplemental group. Taken together, our results revealed that fenugreek seed extract can be used as an effective dietary supplement for dairy heifers to improve intake and digestibility, and alter the host transcriptome toward improved energy and amino acid metabolism, improved antiviral immune status, and reduced oxidative stress damage.
379 Impacts of Serecia Lespedeza and Black Seed Meal Dietary Supplementation on Sperm Quality and Fertilityvariables of Male Goats
Authors: Namani Sharath Chandra , Kolikapongu Ramya Sri , Chelkapally Sai Chandan , Heikal Rania , Neha Ayesha , Shaik Arshad , Pech Cervantes Andres A , Whitley Niki C , Kouakou Brou , Terrill Thomas H , Moawad Adel R R
Published: November 2023

Infertility is a significant issue in the livestock industry. Parasitic infestation is a significant cause of infertility in small ruminants. Sericea Lespedeza (SL) and Black seed meals (BSM) have been reported to improve sperm quality and fertility in rodents; however, little is known about their effects on livestock. Our aim was to evaluate the effects of feeding male goats with SL and BSM on their sperm quality and fertility. We conducted an 8-week pen study involving 60 mature, intact Spanish bucks divided into four groups. The animals were randomly assigned to four groups and fed diets of 60% pellets and 40% concentrate. The treatment groups were SL (n = 15), SL+ BSM (n = 15), alpha-alpha with deworming (n = 15), and alpha-alpha without deworming (naturally parasitized n = 15). At the end of the trial, scrotum circumferences (SC) were measured, and the animals were transported to a processing facility for slaughter. Testicles and epididymides were collected after slaughter for measuring their weights and lengths. Epididymal spermatozoa were retrieved and evaluated for their motility, concentration, viability, abnormalities, and membrane integrities. No significant differences were observed in SC and sperm motility between the 4 groups (ranged 56.7% to 67.3%). However, sperm cell concentrations, viable sperm, and the percentage of sperm with intact acrosome were greater (P < 0.05) in SL and SL+BSM groups than in the other 2 groups. Furthermore, the sperm abnormalities were less (P < 0.05) in SL and SL+BSM groups. In conclusion, dietary supplementation with SL and BSM significantly improved sperm viability and reduced sperm abnormalities in goats. This study assures the potential benefits of SL and BSM on the fertility of male goats.
39 Developing Precision Agriculture Tools to Capture Behavior and Performance in Extensively Managed Sheep
Authors: Hess Andrew , Huber Scott , Bergeron John H , McCuin Gary , Hess Melanie , Shane Tracy , Karl Jason , Cox Mike , Washington-Allen Robert
Published: November 2023

Rangeland livestock provide a great opportunity to capture resilience traits due to the significant amount of the year spent grazing a resource-limited environment where they are exposed to extreme weather, predators, and varied terrain. Capturing the ability of an individual to cope with these stressors has the potential to improve animal welfare and productivity in the face of climate change. These measurements need to occur over the course of time of an animal in such an environment or capture the sum of the ability of the animal to cope with the environment. To do this, measurements of resilience and efficiency will be a useful tool to make continued improvement in rangeland livestock through genetic selection. However, the high-throughput phenotyping typically required to capture resilience traits is challenged by the remote location, limited or no access to power and internet, and limited manpower for data collection. Therefore, such tools need to be self-sustaining, automated, and cost-effective to be able to capture data on a large number of individuals in a rangeland setting. To this end, we have been exploring the use of precision livestock tools to capture sheep performance in a rangeland environment. We are currently working on developing a portable walk-over-weighing system to automatically capture an individual’s weight that uses a combination of solar powered portable batteries and an RFID system with the aim to make a compact weighing system that can easily be transported in rough mountainous terrain. This system can be used to capture longitudinal weights in challenging environments, which can be used to develop indicators of resilience, such as the variability in weight over time or changes in weight due to chronic environmental stressors such as a heat wave. Because it is RFID-based, the data can also be used to take stock inventory to track possible predation events or other stock losses. We are also using low-cost commercial-off-the-shelf GPS units to capture animal behavior in these environments. These data can be used to derive a multitude of traits relating to land-use behavior, including water usage and daily distance traveled. The data can also be used to capture social interactions, such as ewe-lamb relationships. While the information content is high for these datatypes, there are also challenges associated with missing or unreliable data. We are currently exploring methods to combat these challenges to provide robust measurements of performance. Through these data, we aim to develop traits that integrate animal performance and behavior to identify animals that are better suited to a rangeland environment. We expect that breeding of such animals will result in a positive impact on productivity, a reduced impact on the ecosystem, and lower mortality rates, thereby improving the sustainability of livestock production systems.
392 Evaluation of Assessment Strategy on Student Retention of Knowledge in Sequential Animal Science Courses
Authors: Kuderka Alison M , Vautier Allison N , Speidel Scott E , Mark Enns R , Cadaret Caitlin N
Published: November 2023

As students progress through their undergraduate education, information from previous classes culminate to lay a foundation for academic success in upper-level courses. However, there is a lack of evidence and implementation for formative assessment methods in undergraduate education. Traditional summative assessments are often cited as being high stress by students and are studied for by cramming material. Both high stress and cramming can reduce long-term knowledge retention in the average student, which is problematic when students need to retrieve this knowledge for future classes. Thus, our objective was to evaluate student knowledge retention coming from a prerequisite course divergent in assessment strategy and/or environment. The prerequisite course, ANEQ 328: Foundations of Animal Genetics, used either 4-unit exams or 16 weekly quizzes with identical questions to assess learning of course material. The course was either delivered in person or online, covered the same material, and all students received the same post-test at the end of the semester. Furthermore, in the quiz-based courses students were surveyed at the end of the semester to gather perceptions of learning with varying course formats. In the subsequent course, ANEQ 330: Principles of Animal Breeding, the same post-test from ANEQ 328 was given as a pre-test. On the pre-test, students were asked to indicate in which year and semester they completed ANEQ 328 so an assessment type and environment could be identified. Scores on the pre-test were analyzed as a measurement of retention across courses, and effects of time elapsed between courses, the type of assessment strategy used, and the physical environment in which the class was delivered were considered. Time between courses impacted retention, as students who took ANEQ 330 within two semesters of ANEQ 328 had higher scores (P < 0.05) than all other timepoints. Student retention was not different between students who took the prerequisite course online or in-person (7.65 ± 0.19 and 7.61 ± 0.23, respectively). Additionally, student retention was not impacted by whether the prerequisite course used quiz or exam-based assessment strategies (7.58 ± 0.16 and 7.89 ± 0.33, respectively). These data indicate that both assessment strategies are interchangeable when considering impacts on long-term retention; however, survey data showed that formative assessments, such as quizzes, are better received than summative assessments, as they help to ease testing anxiety, better pace student learning, and provide consistent feedback. Therefore, instructors may choose to use formative assessments to improve student perceptions of learning without impacting knowledge retention.