Rumen Undegradable Protein Research Articles

Dietary effects of protected fat, soybean meal, and heat-treated soybean meal on performance, physiological parameters, and behavioral measurements of early-fattening Hanwoo steers under heat stress conditions.

This study evaluated the effects of increased levels of dietary total digestible nutrient (TDN) and crude protein (CP) using protected fat (PF), soybean meal (SB), and heat-treated soybean meal (HSB) on performance, physiological parameters, and behavioral measurements of early-fattening Hanwoo steers under heat stress conditions. Thirty-six steers (480.9 ± 58.6 kg, 15.9 ± 1.4 months) were assigned to 4 treatments: Control (TDN 75%, CP 15%, rumen degradable protein [RDP]:rumen undegradable protein [RUP]=62:48), PF (TDN 82.5%, CP 15%, RDP:RUP=62:48), PF+SB (TDN 82.5%, CP 16.5%, RDP:RUP=62:48), and PF+SB+HSB (TDN 82.5%, CP 16.5%, RDP:RUP=48:52) for a total of 16 weeks with division of 4 weeks. The average temperature-humidity index (THI) was 82.9 (1st; Moderate), 76.9 (2nd; Mild), 70.9 (3rd; Comfort), and 65.8 (4th period; Comfort). Dry matter intake during whole period did not differ among treatments but decreased by 34% and 19%, respectively during 1st and 2nd compared to 4th. Average daily gain (ADG) of PF+SB+HSB was higher (p<0.05) than that of Control during the 1st period, and those of both PF+SB and PF+SB+HSB were higher (p<0.05) than Control during the 2nd. The ADG during whole period was in the order of PF+SB+HSB (1.23), PF+SB (1.18), PF (1.11), Control (0.98 kg/d) (p<0.05). As THI increased, rectal temperature and all blood parameters increased, while blood glucose levels decreased (p<0.05). Behavioral changes during 1st period compared to 3rd included decreases in Lying (24%), Walking (48%), and Eating (40%), and increases in Total standing (50%) and Drinking (43%) (p<0.05). Rumination during standing was 38% higher, and Rumination during lying was 32% lower (p<0.05). This study demonstrates 10% of increased levels of dietary TDN using PF and CP considering RUP can prevent performance reduction in early-fattening of heat-stressed Hanwoo steers and have positive effects on performance recovery from post-heat stress.

Ruminal degradation and intestinal digestion of developed oat (Avena sativa L.) varieties in comparison with barley grain in dairy cows

This study aimed to evaluate the ruminal degradation and intestinal digestion of nutrients of two cultivars of oat grains (CDC Nasser and CDC Seabiscuit) in comparison with a barley grain (CDC Meredith that was considered the control treatment) in dairy cows. Nasser showed higher rumen undegradable protein (RUP; P &lt; 0.01) and intestinal digestible protein ( P &lt; 0.01) than Seabiscuit or control. However, the total digestible protein was not different among grain varieties ( P = 0.25). The in vitro intestinal digestibility of RUP (dIBP) for Nasser was higher than control ( P = 0.02); however, the dIBP in Seabiscuit did not differ from other cultivars. The intestinal digestible rumen bypass starch and total digestible starch were lower in the oat grain varieties than in the control ( P &lt; 0.01). The truly absorbed protein supplied to the small intestine (DVE) was highest for control, intermediate for Seabiscuit, and lowest for Nasser ( P &lt; 0.01). Moreover, control showed a higher estimated feed milk value than oat varieties ( P &lt; 0.01). In conclusion, Seabiscuit shared similar rumen degradation and intestinal digestibility with control suggesting that Seabiscuit oat grain could in some extension replace barley grain in diets for dairy cows.

PSXI-23 Development of sub-models to estimate protein requirements and supply of lactating dairy cows using machine learning algorithms

Abstract The objectives of this study were to develop sub-models for predicting protein requirements and supply, encompassing 1) net protein for maintenance (NPm), 2) lactation (NPl), 3) rumen undegradable protein (RUP), and 4) duodenal microbial nitrogen (MicN) from the feed protein. The dataset used in this study was constructed by integrating in vivo experimental data collected from open databases (the National Animal Nutrition Program) and articles (Journal of Dairy Science), which includes a total of 1,779 observations from 436 publications. In the development of the model, animal information and feed chemical components were used as candidate variables, and two types of machine learning algorithms, Random Forest Regression (RFR) and Support Vector Regression (SVR) were employed. After testing, the following predictors were selected for predicting: 1) NPm: body weight (BW) and dry matter intake (DMI), 2) NPl: BW, DMI, days in milk (DIM), and dietary organic matter (OM) and crude protein (CP) contents, 3) RUP: DIM, DMI, dietary DM content, and CP fraction intake (B and C), and 4) MicN: DIM, DMI, DM, dietary neutral detergent fiber (NDF) content, CP fraction intake (A, B, and C). The selected models were assessed using a cross-validation method with the following statistical metrics including the coefficient of determination (R2), root-mean-square error of prediction (RMSEP), residual analyses, and concordance correlation coefficient (CCC). For the RUP and MicN models, they were compared with the NASEM (2021) model. In predicting NPm, both SVR and RFR algorithms demonstrated increased precision (R2 = 0.965 vs. 0.969) and accuracy (RMSEP = 9.7 vs. 9.2 g/d); however, during residual analysis, the RFR model showed a statistically significant slope bias (P &amp;lt; 0.05). In the NPl prediction, the RFR algorithm showed slightly greater performance compared with SVR (R2 = 0.864 vs. 0.814 and RMSEP = 86.7 vs. 98.5 g/d). However, similar to the NPm prediction, the RFR model displayed a statistically significant slope bias (P &amp;lt; 0.05). In the supply model, the RFR model exhibited the greatest precision and accuracy in predicting RUP (R2 = 0.60, RMSEP = 0.326 kg/d, and CCC = 0.71) without any biases. This model achieved a 2.37-fold increase in R2 and a decrease of 0.111 kg/d in RMSEP compared with the NASEM model. As for MicN prediction, the SVR model performed the best (R2 = 0.76, RMSEP = 42.4 g/d, and CCC = 0.86) without biases. This model attained a 19-times improvement in R2 and a reduction of 38.7 g/d in RMSEP when compared with the NASEM model. In conclusion, the models developed using machine learning algorithms can be helpful for accurately and precisely predicting protein requirements and supply based on animal information and the chemical composition of feed.

PSXII-11 Impact of pre-breeding and breeding supplementation in May-born range heifers on growth rates and reproductive performance

Abstract Our objectives were to determine the impact rumen undegradable protein (RUP) supplementation prior to and during the breeding season had on growth rates and reproductive performance in May-born yearling range heifers. This study was conducted over a 3-yr period at the University of Nebraska, Gudmundsen Sandhills Laboratory (GSL) near Whitman, NE and utilized May-born Red Angus x Simmental crossbred heifers [n = 192; weaning body weight (BW) = 200 kg ± 28 kg]. Heifers were randomly assigned by pre-breeding BW to one of two treatments: 1) received 0.908 kg of a dried distillers grain supplement (DDGS; Supp, n = 66) pre-breeding through the breeding season or 2) received no supplement (NoSupp, n = 138). Each year, treatments were initiated in July and ended in August (55 ± 3 d). Using a C-Lock Smart Feeder (Rapid City, SD) heifers had individual access to their allotted DDGS supplementation. On average, NoSupp heifers consumed 0.09 kg/d (yr 1) and 0.02 kg/d (yr 2 and 3); whereas, Supp heifers averaged 0.59, 0.74, and 0.76 kg/d in yr 1, 2, and 3, respectively. Heifer BW was collected pre-trial (May), pre-breeding (July), breeding (August), pregnancy diagnosis (October), and pre-calving (April). Body condition score (BCS) was collected at pregnancy diagnosis (October) and pre-calving (April; Yr 1 and 2). Before each breeding season, two blood samples were collected 10 d apart to determine pubertal status. Heifers were synchronized with a single 5 mL intramuscular injection of prostaglandin F2 alpha (Lutalyse, Zoetis, Parsippany, NJ) 5 d after bull turnout during a 30 d natural service breeding season. Pregnancy diagnosis was determined via rectal ultrasound in October. No differences (P &amp;gt; 0.12) in BW were noted among treatments for all measurement timepoints. Moreover, SUPP heifers had greater (P &amp;lt; 0.02) average daily gain (ADG) from pre- trial to pregnancy diagnosis compared with NoSUPP heifers. However, there was no differences (P = 0.11) in ADG from pregnancy diagnosis to pre- calving. At pregnancy diagnosis (October), a treatment x year interaction (P = 0.02) for BCS was present where Supp heifers had a greater BCS than NoSupp heifers in yr 3. Heifer BCS pre-calving was not affected (P = 0.12) by treatment. There was a greater percentage (P &amp;lt; 0.01) of SUPP heifers cycling compared with NoSUPP heifers. However, there were no differences (P &amp;gt; 0.24) in pregnancy rates, the percentage that calved in the first 21 d, calf birth BW, or subsequent calving date. Ultimately, this study implies that providing a RUP supplement prior to and during the breeding season will increase the percentage of heifers that are cycling before breeding and have a greater ADG through pregnancy diagnosis; however, supplementation will not impact other reproductive parameters or BW gains.

Effects of supplemental rumen-degradable protein, rumen undegradable protein, and energy on performance of growing beef steers grazing corn residue

Effects of supplemental rumen-degradable protein, rumen undegradable protein, and energy on performance of growing beef steers grazing corn residue

Optimizing protein, energy, and protein degradable ratios to enhance in vitro ruminal fermentation and reduce methane gas emission

Abstract The traditional approach to feeding ruminant is based on the needs of protein and energy to enhance production and productivity. It is crucial to note the protein degradability in feed as microbial rumen needs ammonia from rumen degradable protein (RDP), while ruminant needs bypass protein also known as rumen undegradable protein (RUP) alongside microbial crude protein. Through the use of an in vitro technique, the recent study aimed to determine the optimal level of protein, energy, and RDP:RUP ratio in the diet of beef cattle by observing VFA partial production, protozoa population, and methane gas emissions. Various dietary treatments were formulated (based on dry matter content) comprised three protein levels (12%, 14%, and 16%), two energy levels (65% and 70%), and three RDP:RUP ratio levels(55:45 for low RDP, 60:40 for medium RDP, and 65:35 for high RDP). The study followed 3x3x2 factorial randomized block design with three replications. The dietary treatments were incubated with buffered rumen fluid. This study showed acetic, propionic, and butyric acid production were influenced by protein, energy, RD:RUP ratio (P&lt;0.05). Meanwhile, protozoa population and methane gas emission were reduce by dietary protein, energy, and RDP:RUP ratio. In summary, dietary protein, energy, and RDP:RUP ratio impacts the production of VFA, protozoa population, and methane gas emissions. The diet comprising 14% dietary protein, 70% energy, and 60%:40% of RDP: RUP optimizes the production of VFA, while simultaneously reducing protozoa population and methane gas emissions.

Nutritional Evaluation of Milk Thistle Meal as a Protein Feedstuff for Diets of Dairy Cattle.

The objective of this work is to investigate the chemical and nutritional value of milk thistle meal (MTM) in order to improve it and to provide theoretical support for its application in dairy cattle production. MTM was assessed in comparison with seven conventional protein feed sources, namely, soybean meal (SBM), cottonseed meal (CS), canola meal (CN), palm kernel meal (PK), rice bran meal (RB), corn germ meal (CG), and sesame meal (SS). The chemical composition of these feedstuffs was assessed using wet chemical analysis, the Cornell Net Carbohydrate and Protein System was used to evaluate the carbohydrate and protein fractions, and the in situ nylon bag technique and the modified three-step in vitro method were used to assess the rumen degradation and intestinal digestibility. Additionally, Fourier transform infrared technology was used to determine the feedstuff protein spectral molecular structure and its amino acid profile was also assessed. The result showed that MTM acid detergent fiber, lignin, unavailable nitrogen, and non-degradable carbohydrate content were higher than those of the other feedstuffs. It had a 17% and 36% rumen effective degradation rate of neutral detergent fiber and dry matter, respectively, and had the lowest small intestinal rumen undegradable protein digestibility rate. It was low in leucine, histidine, arginine, and proline, but high in methionine. The total area of amide I and amide II in the protein secondary structure was similar to that of CN and CS, and the amide I and II ratio was not different from that of RB. To sum up, MTM has a poor carbohydrate composition and is high in fiber but, in comparison to most other protein feeds, has a higher crude protein rumen effective degradation rate, similar to that of SBM, and it is a good source of methionine, a limiting amino acid. Hence, its nutritional value can be further improved for application in dairy feeding through processes such as microbial or enzymatic fermentation.

87 Evaluating the effects of an amino acid-formulated diet on ruminal fermentation in vitro

Abstract The objective was to determine the effect of an amino acid-formulated diet on ruminal fermentation in vitro. While most amino acid-formulated diets focus on improving the amino acid composition of rumen undegradable protein, additional benefits to microbial fermentation within the rumen are unknown. The experiment was a completely randomized design with a factorial treatment arrangement (2 donor diets and 2 substrates). Four ruminally cannulated steers were fed one of two donor diets: control (CON; 55% dry rolled corn, 20% corn silage, 15% dry distiller’s grain, and 10% supplement) and amino acid-formulated (AAF; 51% dry rolled corn, 15% corn silage, 14% dry distillers grain, 10% heat-treated soybean meal, and 10% supplement). After a 30-d diet adaptation period, rumen fluid was collected and pooled by donor diet for the in vitro fermentation. Additionally, two different substrates were used to represent each donor diet. Flasks contained 2.5 g dry matter (DM) of substrate and 150 mL of rumen fluid mixture (2 McDougall’s buffer:1 rumen fluid). Treatments were evaluated in triplicate flasks in two replicated runs for a total of six observations per treatment. Four sealed Ankom F57 bags were filled with 0.25 g DM of substrate each to facilitate measuring in vitro DM disappearance (IVDMD). Flasks were incubated at 39°C with sample aliquots collected at h 0, 4, 8, 12, and 24 to determine pH, ammonia, and volatile fatty acids (VFA). Data were analyzed using the MIXED procedure of SAS 9.4 with a repeated measures analysis. Ammonia, pH, and VFA were analyzed with effects of donor diet, substrate, time, and all interactions. A treatment by hour interaction was detected (P &amp;lt; 0.01) for pH; fluid from steers fed CON was greater than AAF at h 4, 8, 12, and 24. A treatment by hour interaction was also detected (P = 0.02) for ammonia; fluid from steers fed CON was greater than AAF at h 24, but was not different at other time points. Total VFA was affected by hour (P &amp;lt; 0.01) as it increased over time, but substrate did not have an effect (P = 0.21). A treatment by hour interaction (P = 0.06) tended to be observed for molar proportions of acetate as AAF and CON were similar at h 0 but AAF was increasing greater than CON over time. A treatment by hour interaction was observed (P = 0.01) for molar proportions of propionate; at h 4 at 8, CON was greater than AAF. No effect (P ≥ 0.32) of donor diet, substrate or their interaction were observed on IVDMD. Overall, an amino acid-formulated diet for cannulated steers did impact ruminal fermentation in vitro, mostly altering molar proportions of volatile fatty acids and ammonia release from protein degradation.

Effect of feeding different levels of rumen undegradable protein on growth and economics of production in female crossbred calves

Effect of feeding different levels of rumen undegradable protein on growth and economics of production in female crossbred calves

Effect of Steam Pressure Toasting Duration on Snowbird Faba Bean Seeds and the Impact on the Intestinal and Metabolic Characteristics in Dairy Cows

The response of feedstuffs to thermal processing depends on the type of feed and the thermal processing methods being applied. Steam pressure toasting (SPT) has been used to modify the nutrient degradability and enhance the nutritional quality of pulses, including faba bean seeds (FBS). Strategic feeding approaches are essential for balancing diets and maintaining adequate nutrition, especially in high-performing ruminants. This research aimed to determine the effects of SPT duration in FBS on the intestinal and metabolic characteristics of dairy cows. Faba Bean seeds (three harvesting years) were processed at 121 °C for 0, 30, 60, 90, and 120 min. Rumen degradation and intestinal digestion were determined using the in situ and modified in vitro three-step techniques. The true protein supplied to the small intestine was also determined using the NRC and DVE systems. Our results showed a reduced total digested DM (TDDM) with longer SPT duration (quadratic, p = 0.02). The intestinally digested crude protein (IADP) increased from 62 to 220 g/kg DM with 0 to 120 min of SPT, respectively (p &lt; 0.01), whereas the total tract digestible starch (TDSt) gradually decreased from 321 to 182 g/kg DM based on SPT time (p &lt; 0.01). On the other hand, the truly digested protein in the small intestine (DVE) and the total metabolizable protein (MP) increased from 138 to 282 g/kg DM and 129 to 282 g/kg DM, respectively, with 0 to 120 min of SPT (quadratic, p &lt; 0.01). The Feed Milk Value (FMV), based on both the DVE/OEB and NRC dairy nutrition systems, also increased with SPT (Quadratic, p &lt; 0.01). The processing of FBS with SPT at 121 °C effectively reduced the highly degradable protein fraction in the rumen, shifting to a higher rumen undegraded protein (RUP) which was able to reach the small intestine. In the current study, the total MP, DVE, and FMV in dairy cows showed an overall increase with SPT in FBS.

Nucleic acid-extracted torula yeast from the paper industry as a protein feed for ruminants: A comparison with soybean meal.

We compared nucleic acid-extracted torula yeast (NTY) with soybean meal (SBM) to evaluate NTY as a potential protein feed for ruminants in a metabolic trial using four castrated male goats. NTY was replaced isonitrogenously with SBM at a 25% crude protein (CP) level on a dry matter (DM) basis. NTY has 55% CP and 74% total digestive nutrients on DM. Absorbed N was lower on the NTY diet, but since the urinary N excretion was lower on the NTY diet, no significant between-diet difference in retained N was observed. The efficiency of N utilization (retained N/absorbed N) was significantly higher on the NTY diet. The Lys and Met contents (presumed limiting amino acids for dairy cattle) were higher in NTY than SBM, which may be why N utilization efficiency was higher for the NTY diet. Ruminal ammonia-N and blood serum N were lower on the NTY diet, suggesting that NTY has more rumen undegradable protein than SBM. There was no significant between-diet difference in the visceral disorder indicators or antioxidant activities. Our results indicate that NTY is a safe protein feed with a high CP ratio and high-quality amino acid profile for ruminants that is equivalent to SBM.

Malic acid-heat treatment of oil cakes enhances rumen undegradable protein for effective protein utilization in buffaloes (Bubalus bubalis)

Malic acid-heat treatment of oil cakes enhances rumen undegradable protein for effective protein utilization in buffaloes (Bubalus bubalis)

Effect of Tannin Inclusion on the Enhancement of Rumen Undegradable Protein of Different Protein Sources

Tannins can be utilized to increase rumen undegradable protein (RUP) by their capacity to form complexes with diverse nutrients present in the feed. In that regard, high-performance ruminants demand elevated RUP levels. The objective of this study was to evaluate the effects of incorporating varying levels of tannin into three protein sources (cottonseed, peanut, and soybean meals) on ruminal kinetic parameters, ruminal fermentation, and intestinal digestibility. Thus, three in situ experiments were conducted to investigate the ruminal degradation kinetics, where Fraction A represents the soluble portion, Fraction B relates to the portion potentially degraded in the rumen, and kd denotes the degradation rate of Fraction B, for both dry matter (DM) and crude protein (CP) in the rumen. Additionally, the study assessed dry matter effective degradability (ED), rumen undegradable protein (RUP), and intestinal digestibility (ID). These experiments utilized three cannulated animals for the in situ incubations. Regarding cottonseed meal in terms of DM degradation kinetics, tannin inclusion had a quadratic effect on fraction A (p &lt; 0.01), B (p = 0.10, trend), kd (p = 0.03), and ED (p &lt; 0.01). Fraction A of CP had a cubic effect (p = 0.03), being greater for the control compared with the other treatments. The inclusion of tannin linearly increased RUP (p &lt; 0.01). The RUP proportion increased 29, 33, and 45% when 20, 40, and 60 g/kg tannin were used, respectively, compared to the control. For peanut meal, the A fraction of protein and RUP responded quadratically as tannin was included in peanut meal (p &lt; 0.01). However, tannin levels did not affect fraction B of protein and ID. Regarding soybean meal, fractions A and B of DM and ED had cubic effects (p &lt; 0.01), being greater for the control compared with the other treatments, and responded quadratically as tannin increased. Also, tannin inclusion had a cubic effect on fractions A and B of protein, RUP, and ID (p &lt; 0.01). The cubic behavior showed greater B fraction and ID and lower A fraction and RUP for the control compared other treatments (p &lt; 0.01). Tannins offer a promising avenue for elevating RUP levels in diets featuring cottonseed and peanut meals. Nevertheless, no advantages were observed when treating soybean meal with tannin.

PSIX-22 Performance, Digestibility, and Blood Parameters in Pregnant Beef Cows Fed Total Mixed Ration Silages

Abstract The aim of this study was to investigate the effects of two total mixed ration (TMR) silages (low and high rumen undegradable protein; RUP) on digestibility, blood parameters, and performance in pregnant beef cows. Thirty-three mid-gestation (~130 d of gestation) Tabapua beef cows were randomly assigned to 1 of 2 treatments: 1) a TMR silage containing Brachiaria grass, soybean hulls, urea, and mineral mix (low RUP; n = 16) or 2) a TMR silage containing Brachiaria grass, DDG, and mineral mix (high RUP; n = 17). The concentration of A1 fraction was, on average, 12.9% and 34.0% of N in low and high RUP silages, respectively. A preservative with a blend of organic acids, surfactants, and activated propionates was applied in both silages. Pressed bag silos were used to conserve silages for 7 wk. Cows were housed in individual pens for 100 d. During a 4-d digestion period (at 50 d of housing), fecal samples were collected for measurement of nutrient digestibility using undigested neutral detergent fiber as a marker. Blood parameters were collected at the last day of housing. Statistical analysis of experimental data was performed using the GLM procedure of SAS 9.4. Diet, calf sex (male or female), and interactions between these factors were considered fixed effects. No differences were obtained for initial BW. High RUP diet showed greater final BW (P = 0.0004) and ADG (P = 0.0003). Cows fed high RUP gained 50 g/d, while cows fed low RUP diet lost 445 g/d. Dry matter intake was greater by 23% (P &amp;lt; 0.0001) in cows consuming high RUP silage. Dry matter, CP, and NDF digestibility did not differ between treatments. Regarding blood parameters, no differences were observed for glucose at 0 h and 4 h post-feeding. Plasma urea at 0 h post-feeding was greater in cows fed low RUP silage (P = 0.0003). However, no differences were observed for plasma urea at 4 h post-feeding. The plasma concentrations of non-esterified fatty acids (P = 0.017) and beta-hydroxy-butyric acid (P = 0.002) were greater in cows consuming low RUP diet. Overall, feeding pregnant cows during mid-gestation with TMR silage containing high RUP promotes greater performance.

PSXI-28 Nitrogen Footprint Assessment of Korean Native Beef Cattle Farms: Uncertainty Analysis and Mitigation Scenarios

Abstract Nitrogen (N) lost during beef cattle production accompanies various environmental impacts and has become an increasing concern among agricultural stakeholders. The objective of this study was to quantify the N footprint (NF) of Hanwoo beef cattle production in Korea at the farm gate through a life cycle assessment methodology. Field surveys were conducted on 106 farms across nine provinces to evaluate the NF of Hanwoo beef farms. N losses were calculated using emission factors using the refined Intergovernmental Panel on Climate Change (IPCC) guideline and expressed as NF [g N lost/kg of live body weight (LBW)]. Uncertainty and sensitivity analyses were deployed to evaluate the precision of the results and to quantify the variability of the input data. The NF was averaged 132.8 (±61.9) g N/kg LBW. Volatilization was the greatest contributing factor, followed by leaching and denitrification, each representing 68.4, 21.4, and 10.1 percent of the NF, respectively. The uncertainty of the output data was found to be 46.6 percent and was highly associated with emission factors uncertainties. We simulated four feasible mitigation scenarios that are cost effective and do not penalize productivity, and evaluated their capacity for reducing NF of meat: dietary modifications to decrease animal N excretion rates by adjusting the CP and rumen undegradable protein content for steers and fattening cows (A), microorganism additives to reduce volatilization from housing and manure storages through processing excess ammonium to synthesize microbial protein (B), using manure as land fertilizer instead of synthetic fertilizers to decrease denitrification from rice cultivation, and leaching and volatilization from all field types(C), and distributing straw-derived biochar (10 to 20 ton/ha) to the field after fertilizer application to reduce losses from crop production (D).Combining these scenarios demonstrated the potential to reduce NF by 12.3 percent. Overall, our study provides a national metric that can be used to communicate the N uses impact of Korean beef production. The analyses indicate that more precise results could be achieved with future endeavors toward developing country-specific emission factors. Integrating all four scenarios was shown to be the most effective approach to reducing the NF of beef production.

160 Effect of Nexpro on Immune Response and Performance of Finishing Steers

Abstract This study aimed to determine the effect of NexPro on growth performance, carcass characteristics, and markers of immune function in finishing cattle. Angus-cross steers (n = 210) weighing 465 ± 48 kg were used for this 89-day study. Steers were blocked by BW into four treatments: SBM; a control diet with 11% soybean meal on DM basis; NP9 (9% NexPro), NP12 (12%), and NP15 (15%). NexPro replaced dry-rolled corn in the diet as NP inclusion increased. NexPro treatments each had 9 pens and SBM had 8 pens (6 steers per pen). On day 0, steers were implanted with Component TE-200 (Elanco Animal Health). The BW of all steers and bunk refusals were measured on d -1, 0, 26, 61, 75, and 89 and were used to calculate pen gain, DMI and feed efficiency for each period. One steer per pen was selected for blood collection and muscle biopsies collected on d 26 and 75. From d 61 to 89 steers received 300 mg/d of ractopamine hydrochloride (RAC; Actogain; Zoetis). Fresh blood samples were used for immune cell population determination using flow cytometry. Data were analyzed using the Mixed procedures of SAS with pen as the experimental unit and fixed effects of treatment and block. Performance data were analyzed using d 0 BW as covariate. During the pre-RAC period (d 0 to 61) steers fed the SBM treatment ate more (P &amp;lt; 0.001) than steers fed the NP diets. Steers on the SBM diet had the greatest ADG, with NP12 and NP15 intermediate, and NP9 lowest (P ≤ 0.06), with no treatment differences in G:F (P = 0.26). However, during RAC DMI improved in all NP treatments, and were not different (P = 0.32) from SBM. During the RAC period, ADG tended to be greater (P = 0.09) in NP15 than all other treatments, and G:F was improved (P = 0.01) in NP15 compared with other treatments. Carcass-adjusted BW and ADG, and HCW were less in NP9 (P ≤ 0.02) but similar between SBM, NP12 and NP15. Carcass-adjusted G:F did not differ by treatment (P = 0.50). On d 26, NP12 and NP15 had greater frequencies of live gamma-delta T cells, and on d 75, NP15 had the greatest frequency of these cells (P ≤ 0.016). All NexPro treatments had greater percentages of CD45RO positive B cells on d 75 (P = 0.03) and increased frequency of live total natural killer cells from d 26 to 75 (P = 0.06). The less than expected DMI and greater rumen undegradable protein in NexPro may have caused NP9 to be RDP deficient. However, the greater inclusions of NexPro supported excellent cattle gains, similar or better than SBM.

Brachiaria Hybrid and Pennisetum purpureum Supplemented with Pueraria phaseoloides Increased the Concentration of Rumen-Undegradable Protein in Forages for Ruminants

Supplementing tropical grasses with leguminous forages is known to improve the nutritive value of forage-based diets. However, it is not clear how basal grass forages supplemented with Kudzu (Pueraria phaseoloides) affect the nitrogen (N) and crude protein (CP) fractions of grass/legume forages. The aim of this study was to determine the N and CP fractions and in vitro ruminal CP degradability of Brachiaria hybrid (B. ruziziensis × B. decumbens × B. brizantha) and elephant grass (Pennisetum purpureum) supplemented with Kudzu at a target CP content of 133 ± 0.6 g/kg of dry matter (DM). The grass/legume forages were evaluated for total N, buffer-soluble N (BSN), buffer-insoluble N (BISN), non-protein nitrogen (NPN), neutral detergent-insoluble N (NDIN), acid detergent-insoluble N (ADIN), CP fractions A, B1, B2, B3, C, rumen-degradable protein (RDP), rumen-undegraded protein (RUP), and in vitro ruminal CP degradability. The CP concentration of Kudzu was 217 g/kg DM, while grass forages ranged between 79.9 and 112 g/kg DM. The BISN, CP degradability parameters b, and potential degradability were approximately 56, 41, and 74%, respectively, higher in grass forages supplemented with Kudzu. The concentrations of RUP in the grass forages (23.9–32.5 g/kg DM) were significantly improved when they were supplemented with Kudzu (72.0–79.9 g/kg DM). Therefore, we concluded that basal grass forages supplemented with Kudzu to a target CP content can improve the amount of RUP supplied by the forage portion of the diet. This can have a positive effect on forage utilization and animal performance while reducing the cost to feed for ruminants.

Comparative evaluation of nutrient composition, in vitro nutritional value, and antioxidant activity of de-oiled meals from walnut, hazelnut, almond, and sesame.

This study aimed to establish a comparative database on the chemical composition, in vitro nutritional value, and antioxidant activity of the de-oiled meals produced from walnut, hazelnut, almond, and sesame seeds from the ruminant nutrition perspective. The meals were provided in dried form after their oil harvest using the cold-pressing oil extraction method. Crude protein (CP) constituted the major component of the meals and was the greatest in walnut and almond (average of 45.6% of dry matter (DM)], intermediate in hazelnut meal (41.4%), and least in sesame meal (33.3%)). Potassium was the most abundant mineral in walnut, hazelnut, and almond meals, followed by phosphorus, calcium, and magnesium. The CP fractions determined using the Cornell Net Carbohydrate and Protein System were largely different across the meals, with fraction A being the greatest in hazelnut (40.9% of CP) and intermediate in almond, sesame, and walnut meals (11.4% of CP). The unavailable CP fraction (fraction C) was the least abundant fraction in all meals, ranging from 0.13% of CP in walnut to 3.30% of CP in hazelnut meal. Oleic and linoleic acids were the predominant unsaturated fatty acids, and palmitic acid was the principal fatty acid in all meals analyzed. The fractional degradation rate (h-1) ranged from 0.043 in almond meal to 0.017 in walnut meal. In vitro intestinal CP digestibility (% of rumen-undegraded protein) ranged from 91.6 in hazelnut meal to 97.2 in almond meal. Total phenolics expressed as milligram tannic acid equivalent/gram DM was greatest in walnut meal (11.9), resulting in the greatest antioxidant activity recorded for walnut meal (83.2%). This study provided a database on the nutrient composition, in vitro nutritional value, and antioxidant capacity of the selected de-oiled meals. Additional investigation is needed to identify the in vivo response of their inclusion in the diet of ruminants.

Dairy Cows Transition Period Feeding and Management

Proper feeding during the pregnancy and post-pregnancy period, determines the milk Production, ensuing lactation and as well as, the reproductive efficiency of the animal. 3 weeks before and 3 weeks after parturition are very important because a dramatic physiological and metabolic adaptation occurs during this period which is called the transition period. The Nutritional imbalances are caused by the low quality of desired nutritious rations, reduced appetite, and low ingestion which are responsible for depressed performance, specifically during the transition period. The absence of knowledge and skills of farmers in feeding management during the transition period exacerbates the situation. The metabolic changes, metabolic adaptations, Mechanism of a Transition period, transition period feeding management to prevent disorder, Decreased dry matter intake (DMI), Nutrient requirements, Infectious diseases and metabolic disorders, Nutritional management to Ease out the Transition Period, Management of the transition period, Feed additives supplementation and nutritional-management strategies to passage transition period are discussed by this review paper. Simultaneously, with the growth of the fetus, the nutrient requirements increase and are at their peak before parturition as well as immediately after parturition. The peak milk production reaches about 5–8 weeks postpartum, while the diet consumption peaks at 10–14 weeks postpartum. So, dairy cows will typically suffer a 6–8-week period of negative energy balance during the postpartum period. The requirement energy of the mammary at 4 days postpartum is more than three times than that of the uterus, with a simultaneous increase in the requirement of metabolizable protein, especially of methionine and lysine. The high metabolic incidence of infectious diseases is responsible for the high incidence of inflammatory conditions, mostly immediately after calving. To prevent mentioned diseases, pro-inflammatory cytokine release should be avoided postpartum. The body reserves mobilization, especially fat and protein; and hepatic gluconeogenesis takes place immediately after parturition leading to increased levels of β-hydroxy butyric acid and non-esterified fatty acids, which act as a gateway for several metabolic diseases. The phase of transition may eased by increasing DMI, feed conversion efficiency, density of ration, and protein supplements rich in rumen un-degradable protein; by using anionic mineral mixture, optimizing roughage to concentrate (R: C) ratio, optimum physically effective fiber length of forages/silage/hay, dietary buffers, feed additives such as inflammation modulators, protected nutrients, glucogenic precursors and direct-fed microbial/probiotics.

Protein requirements for pregnant dairy cows

We aimed to estimate the protein requirements of pregnant Holstein × Gyr cows. Sixty-one Holstein × Gyr (HG) cows were used, with an average initial BW of 480 ± 10.1 kg and 5 ± 0.5 yrs of age. Cows were divided into 3 groups: pregnant (n = 43), non-pregnant (n = 12), and baseline (n = 6). Baseline animals were slaughtered before starting the experiment to estimate the initial body composition of the remaining animals. Pregnant and non-pregnant cows received 2 diets: maintenance and ad libitum. Pregnant cows were slaughtered at 139, 199, 241, and 268 gestation days (GD). First, we used data only from non-pregnant cows to determine the requirements for maintenance and growth in adult cows. The requirements of metabolizable protein for maintenance (MPm; g/EBW0.75/d) were estimated using a linear regression between the metabolizable protein intake (MPI, g/d) and average daily gain (g/d), and the MPm was defined as the intercept divided by the average BW0.75. Net protein requirements for gain (NPg; g/d) were estimated by the first derivative of the allometric equation between final crude protein (CP) in the body (kg) and the final EBW (kg). The efficiency of use of metabolizable protein for gain (k) was calculated from the regression between the retained protein (g/EBW0.75/d) and the MPI (g/EBW0.75/d), and k was the slope of this regression. The MPI was estimated by combining microbial protein synthesis (purine derivatives) with the digestible rumen undegradable protein [(total protein intake minus RDP) × intestinal digestibility]. Second, an exponential model was used to fit the protein accumulation in the gestational components in the function of GD. The first derivative of that model was considered the net requirement for gestation (NPgest). The efficiency of protein utilization for gestation (kgest) was calculated by the iterative method using the equation: Δ = MPI - (MPm + NPg/kg + NPgest/kgest). The iteration was performed aiming at a zero deviation between observed MPI and MP estimated by the requirements determined herein. We obtained a value of 3.88 g/EBW0.75/d for MPm. The estimation of NPg can be calculated according to the following equation: NPg = 0.716 × (EBWopen-0.308) × EBGcorrected, where EBWopen is the empty BW (kg) for non-pregnant animals and EBGcorrected is the empty body gain (kg/d) corrected for the gestational component. The k was determined as 0.347. The net protein requirements for gestation (NPgest) were determined as NPgest (g/d) = 0.0008722 × exp(0.01784 ×GD) × (calfweight/35). The efficiency of using metabolizable protein for gestation (kgest) was 0.625. It is important to highlight that different methods of MP estimates should not be mixed and that the proposed method requires the estimate of microbial protein (estimate it via urinary estimates) and might be a limitation for practical application. In conclusion, new studies should be conducted to validate our results and the methodology adopted to determine protein requirements for pregnancy in dairy cows. Due to the pattern of protein accumulation in the gestational components, we suggest that exponential model to describe protein requirements for pregnancy for dairy cows.