Apparent Total Digestibility Research Articles

Effects of the use of phytonutrients in the diet of dairy ruminants: Systematic review

Objective. This systematic review examines the effects of essential oils used as phytonutrients in the diet of dairy animals, considering parameters such as feed consumption, total apparent digestibility, methane emissions and milk production, based on studies published between 2018 and 2023. Material and methods. Bibliographic research electronic method resulted in a careful selection of articles, which were reviewed and tabulated for evaluation. Results. The results show that 51.35% of the articles did not report significant effects of phytonutrients on milk production. However, 66.67% of the studies observed an increase in feed efficiency and 50% reported the presence of effects on apparent digestibility. Furthermore, there was a reduction in methane emissions in animals treated with phytonutrients. Conclusions. Sharing these results with dairy farming professionals can promote more sustainable and effective practices, as well as support future research and innovations in animal nutrition, aiming for both productive efficiency and environmental sustainability.

Effects of biochanin A on lactational performance, nitrogen metabolism, and blood metabolites in dairy cows

Optimizing nitrogen utilization efficiency and mitigating nitrogen losses in cows plays a pivotal role in fostering economic sustainability within contemporary agricultural systems. Biochanin A (BCA), a natural component in red clover, has the potential to improve nitrogen metabolism in dairy cows. The primary objective of this study was to probe the impact of biochanin A supplementation on lactational performance, nitrogen metabolism, and blood metabolites in dairy cows. A complete randomized block design experiment was conducted over 28 d, involving 36 multiparous Holstein cows (comparable milk yield = 37.1 ± 2.90 kg, BW = 642 ± 70.0 kg, days in milk = 92 ± 8.0 d, and parity = 2.4 ± 0.50), which were allocated to three treatment groups: the Control group (with 0 g/d BCA), the Low group (with 10 g/d per cow BCA), and the High group (with 40 g/d per cow BCA). Biochanin A supplementation improved the lactational performance of cows by increasing milk yield by 6.3% (P = 0.007) and feed efficiency by 12.7% (P = 0.009). Total intestinal apparent digestibility was unaffected by BCA supplementation (P > 0.05), but microbial nitrogen was increased by 30.0% (P = 0.002) for promoting nitrogen utilization efficiency by 20.7% (P = 0.004). Milk competent yields (protein, lactose, and non-fat milk solid) were increased with increasing BCA supplementation (P < 0.05). Urea nitrogen levels in plasma and milk were both decreased by BCA supplementation (P < 0.05). Blood routine parameters and plasma biochemical parameters both received no effect by BCA supplementation (P > 0.05). BCA did not affect body health of dairy cows. Additionally, none of the plasma endocrine hormones were affected (P > 0.05). A total of 95 significantly different metabolites were screened from the plasma metabolites of cows in the BCA-added and non-added groups. After performing an enrichment analysis of the metabolic pathways associated with the different metabolites, six specific pathways were identified: bile acid biosynthesis, aspartate metabolism, pyrimidine metabolism, arginine and proline metabolism, the urea cycle, and ammonia recycling. The inclusion of BCA is suggested to enhance milk yield and modulate nitrogen metabolism by influencing relevant metabolites within the metabolic pathways.

Effects of Defatted and Hydrolyzed Black Soldier Fly Larvae Meal as an Alternative Fish Meal in Weaning Pigs.

In Experiment 1, a total of eighteen crossbred ([Landrace × Yorkshire] × Duroc) barrows with an initial body weight of 6.74 ± 0.68 kg were randomly divided into three dietary treatments (one pig per cage and six replicates per treatment) and housed in metabolic cages that were equipped with a feeder and slatted floor to collect urine and feces. In Experiment 2, a total of 96 crossbred ([Landrace × Yorkshire] × Duroc) barrows with an initial body weight of 8.25 ± 0.42 kg were used in the 6-week trial. The pigs were randomly divided into three dietary treatments (three pigs per pen and eight replicates per treatment). In Experiment 1, nutrient composition of defatted black soldier fly larvae meal (BLM) was superior to that of hydrolyzed BLM but lower than that of fish meal (FM). Also, defatted BLM and FM had better apparent total track digestibility (ATTD) of crude protein (CP) and better nitrogen retention (p < 0.05) than hydrolyzed BLM, but there was no significant difference (p > 0.05) between defatted BLM and FM. In Experiment 2, defatted BLM improved (p < 0.05) average daily gain (ADG), feed conversion ratio (FCR), and feed cost per kg gain (FCG) compared with FM. Defatted BLM could replace soybean meal and fish meal as an alternative protein source for weaning pigs.

Essential Oils in Nellore Beef Cattle: In Vivo Impact on Rumen Emissions.

Essential oils (EOs), as rumen additives, decreased CH4 emissions in in vitro trials but results from in vivo studies are still limited. We investigated the effects of Origanum vulgare (OEO) and Thymus vulgaris (TEO) EOs on in vivo methane emissions from Nellore beef cattle. Six adult rumen-cannulated Nellore cattle were used in a double 3 × 3 Latin square design. Treatments consisted of three diets containing either 3 mL OEO per kg of concentrate, 3 mL TEO/kg of concentrate, or no EO addition. The experimental period consisted of three 21 d feeding periods and methane production was measured using the sulfur hexafluoride (SF6) technique from Day 16 to Day 21 of each feeding period. Intake, total apparent digestibility (dry matter as well as neutral and acid detergent fiber), and rumen parameters (pH, ammoniacal nitrogen concentration, and short-chain fatty acids) were also evaluated. The EOs did not decrease CH4 emissions and had no effect on rumen parameters.

Impact of dietary zinc and copper levels on ileal and total apparent nutrient digestibility in growing pigs

This study aimed to evaluate the effect of dietary zinc (Zn) and copper (Cu) levels on their apparent ileal digestibility (AID) and total tract digestibility (ATTD) and that of calcium (Ca), manganese (Mn), iron (Fe), phosphorus (P), and fiber in pigs. The experiment was carried out with six individuals fitted with a T-cannula. Pigs received one of four diets with two levels of Zn (100 [low] and 500 [high] mg/kg) and Cu (40 [low] and 80 [high] mg/kg). High Zn increased AID of Zn and Mn, but decreased that of Ca ( p &lt; 0.05). High Cu tended to improve AID of Cu, but only when high Zn was used (Interaction Zn × Cu, p = 0.051). ATTD of Zn, Cu, Mn, and P was greater in high Zn ( p &lt; 0.05). High Cu also increased ATTD of Cu, but reduced that of Ca ( p &lt; 0.05) as it likely did for ATTD of P in low Zn (Interaction Zn × Cu, p = 0.065). There was an improving trend for ATTD of NDF (Interaction Zn × Cu, p = 0.069), and ATTD of ADF was increased with a combination of high Zn and high Cu (Interaction Zn × Cu, p &lt; 0.05). This research showed that the levels of Cu and Zn modified the digestibility of minerals but also the degradability of fiber.

Use of a novel fodder herb, Commelina species, in Black Head Ogaden lambs: nutrient utilization, weight gain performance, and economic viability

ABSTRACT This study was carried out to determine the effects of supplementing Commelina forage species on nutrient uptake, weight gain, and economic viability in Black Head Ogaden lambs. Twenty yearling lambs were used in four treatments with five replicates in randomized complete block design. The treatments included Teff straw + 120 g dried Moringa stenopetala leaves (DMSL) for treatment 1 (T1), Teff straw + 120 g DMSL + 300 g C.benghalensis (T2), Teff straw + 120 g DMSL + 300 g C.imberbis (T3) and Teff straw + 120 g DMSL + 300 g concentrate (T4). A 60-day feeding trial was followed by a 10-day digestibility investigation. The study used SAS 9.0 for data analysis; the Duncan multiple range test for mean separation and partial budget analysis for financially feasibility testing. With better responses in T4 followed by T3, T2, and T1, supplementation significantly improved total DM, nutritional intakes, and apparent digestibility (P < 0.001). The two Commelina species and conventional concentrate-supplemented treatments resulted in average daily weight gains of 47.58 and 72.69 g, respectively but the former treatments produced higher marginal returns (2.02) than the later ones (0.22). With promising profit, Commelina species could be used as a supplement to improve the animals’ nutrient uptake and growth efficiency.

Apparent nutrient digestibility, metabolizable energy and apparent ileal amino acid digestibility of commercial partially defatted Hermetia illucens meal for laying hens

Abstract A digestibility study with laying hens was carried out to determine the nutritional value of a commercial and representative (batch to batch variance adjusted) insect meal based on Hermetia illucens (HI) larvae, (from black soldier fly) which was the objective in this study. A basal diet (BD; CP 15%), formulated and fed as such and an experimental diet (HD; CP 21%) consisting of BD with inclusion of 18% of the HI meal were used in the study. The BD and HD were fed to eight and six replicate metabolic cages, respectively, with eight Dekalb White laying hens each from 25 to 27 weeks of age. Diets (pelleted with TiO2 as marker) and water were available for ad libitum intake. Excreta was collected during the last three days to determine AMEn and apparent total tract faecal nutrient digestibility coefficients (ATTDC). Distal ileal content was collected at the last day of the experiment to determine apparent ileal amino acids digestibility of diets and HI meal. Using table values for endogenous losses standardised ileal amino acids digestibility coefficient (SIDC) of HI meal were also calculated. Analysed nutrients (g/kg) in HI meal were: 47 moisture, 529 crude protein, 71 ash, 135 fat and thus 218 was calculated as carbohydrates. Determined AME AMEn for HI meal was 3,846 kcal/kg dry matter (DM) and AMEn was 3,498 3,671 kcal/kg DM and ATTDC AFD for crude protein, crude fat and carbohydrates was 0.830, 0.940 and 0.680, respectively. Average SID coefficient for the 18 amino acids was 0.861 86.1%. Among indispensable amino acids SIDC ranged from 0.790% for threonine to 0.950% for phenylalanine and was 0.840% for lysine. These findings highlight that HI meal is an interesting alternative protein source for soybean meal (SBM). Besides market prices and availability, demands for more sustainable poultry production will determine the use of HI meals as alternative for SBM in poultry diets in the near future, especially in regions where SBM is imported from overseas.

PSVI-3 Effects of Different Concentrate Inclusion Levels in Diets Containing Agri002E Sorghum Silage on Intake and Digestibility in Growing Nellore Bulls

Abstract The sorghum hybrid, AGRI002E, sorghum was developed for high dry matter (DM) production per area. However, there are no reports in the literature evaluating the use of this silage with different inclusion levels of concentration on the ingestive and digestive variables of beef cattle. Therefore, this study aimed to access the effects of different concentrate levels in diets containing AGRI002E sorghum silage (SS) on feed intake, ruminal and apparent total tract digestibilities of organic matter (OM), neutral detergent fiber corrected for contaminant ash and protein (apNDF), and starch. Nellore rumen-cannulated bulls (n = 5; BW = 242 ± 5 kg) were used in a 5×5 Latin square design. The experimental treatments consisted of five concentrate levels (0, 200, 400, 600, and 800 g of concentrate/kg of diet DM) in SS-based diets. The concentrates used in the experimental diets were based on corn, soybean meal, sulfated urea, virginiamycin, and mineral supplement. The diets were formulated to provide approximately 120 g of crude protein per kg dietary DM. In the 0% concentrate diet, the protein level was adjusted with sulfated urea. All diets contained the same amount of virginiamycin and mineral supplement. Each experimental period lasted 24 d, with 17 d adaptation, 4 d of total feces collection, and 3 d collection to obtain omasal flow using a double marker technique (indigestible NDF and Co-EDTA). Data were analyzed using MIXED-SAS. Starch and OM intake linearly increased (P &amp;lt; 0.001) with increasing concentrate inclusion. Intake of apNDF decreased linearly (P = 0.018) and tended to be quadratically influenced (P = 0.022) with increasing concentrate inclusion (Table 1). Ruminal digestibility of OM increased linearly (P &amp;lt; 0.001) with increasing concentrate inclusion. Starch ruminal digestibility decreased linearly (P = 0.003) and tended to be influenced quadratically (P = 0.0015) with increasing concentrate inclusion. Ruminal digestibility of apNDF tended to decrease linearly (P = 0.057) with increasing concentrate inclusion. Total apparent digestibility of OM increased linearly (P &amp;lt; 0.001) and apNDF and starch total apparent digestibility decreased linearly (P ≤ 0.002) with increasing concentrate inclusion. Increasing inclusion of concentrate in AGRI002E sorghum silage-based diets increased OM and starch intake, and ruminal and total apparent OM digestibility and decreased apNDF intake and ruminal and apNDF and starch total apparent digestibility.

PSV-15 Effects of Supplementation of Protease to Different Nutrient Density of Diets on Growth Performance, Nutrient Digestibility, Blood Profile, Gas Emission, Fecal Microflora in Growing-Finishing Pig

Abstract This study was conducted to investigate the effects of protease supplementation and different nutrient density of diets on growth performance, nutrient digestibility, blood profiles, gas emissions, and fecal microflora in growing-finishing pigs. Crossbred growing pigs (n = 180; [Landrace × Yorkshire] x Duroc) with an initial body weight (BW; 18.74 ± 3.46 kg) were used for 15 weeks. Pigs were randomly assigned to 6 dietary treatments with 6 replicates of 3 pigs per pen in a 3 ⅹ 2 factorial through the following arrangement: Three groups of protease (1, Basal diets; 2, Protease A: 125 mg/kg protease derived from Streptomyces spp; 3, Protease B: 100 mg/kg protease derived from Bacillus licheniformis) at two different nutrient density diets (1; Basal requirement 2; 0.94-0.98% greater than requirement in dietary protein and 50 kcal/kg in energy). Supplementation of protease significantly increased (P &amp;lt; 0.05) BW at weeks 4 and 6. Also, supplementation of protease increased (P &amp;lt; 0.05) ADG at grower periods and weeks 13 to 15. In addition, improvement (P &amp;lt; 0.05) of ADG was observed in pigs fed a high nutrient density diet (HN) compared with basal nutrient density diet (BN) at grower periods and weeks 13 to 15. In apparent total track digestibility (ATTD) of crude protein (CP), there was increased (P &amp;lt; 0.05) in supplementation of protease at weeks 6 and 13. The HN showed increased (P &amp;lt; .0001) ATTD of CP at 6 weeks. BN increased (P &amp;lt; 0.01) ATTD of CP at week 13. Also, there was interaction (P &amp;lt; 0.05) between nutrient density of diets and supplementation of protease. In ATTD of gross energy, supplementation of protease showed increased (P &amp;lt; 0.05) at week 13. The supplementation of protease in diets decreased (P &amp;lt; 0.05) the concentration of blood urea nitrogen (BUN) at week 13. The supplementation of protease in diets decreased (P &amp;lt; 0.05) the emission of NH3 at weeks 6 and 13. Also, H2S was decreased (P &amp;lt; 0.05) due to supplementation of Protease A in diets. At weeks 6 to 9, average daily feed intake showed a tendency to increase (P &amp;lt; 0.10) when the BN diets were fed. Also, during the entire period, feed conversion ratio tended to increase (P &amp;lt; 0.10) when the BN diets were fed. In conclusion, supplementation of protease reduces NH3 in feces and BUN in whole blood by increasing the digestibility of CP and improved growth performance. Also, diets with high nutrient density improved growth performance and nutrient digestibility in grower periods.

PSIII-12 A Preliminary Evaluation on Novel Tryptophan Additive on Apparent Total Tract and Ileal Digesta of Nutrients in Growing Pigs Using Cannulation Technique

Abstract Amino acids (AA) are the primary structure of proteins. Earlier studies proved that AA contents in the diet are closely related to efficiency of nutrient utilization in pigs. Therefore, we aimed to analyze the effect of tryptophan [(Trp), Trp-proline and calcium-Trp)] supplementation on the apparent total tract digestibility (ATTD) and apparent ileal digestibility (AID) of dry matter (DM), nitrogen (N), energy (GE), and amino acids (AAs) in eight growing pigs [(Landrace × Yorkshire) × Duroc)]. Pigs with average body weights of 25 kg were surgically inserted with post-valve T-caecum cannulation approximately 15 cm anterior to the ileo-cecal junction and randomly assigned to the following diets: CON (corn- soybean meal-distillers dried grain soluble -based basal diet), Trp Pro (CON + 20g/kg Trp Pro), Ca-Trp (CON+ 20g/kg Calcium Trp), and N-free diet using a 4× 4 Latin squares design in duplicates. The novel Trp supplements did not exhibit any significant difference in ATTD and AID of DM, GE, and N digestibility. However, the ATTD of essential AAs such as valine, isoleucine, phenylalanine, lysine, and tryptophan and some non-essential AA like serine, glutamic acid, and glycine was increased (P &amp;lt; 0.05) in novel Trp group. The inclusion of the novel Trp to the diet reduced (P &amp;gt; 0.05) ATTD of threonine but increased the AID of threonine. While other AAs showed the least response to the Trp supplementation. Also, ATTD of methionine tended to be greater in Trp group compared with the CON. In short, the inclusion of 20 g/kg modified form of novel Trp supplementations showed beneficial effects to enhance the AA deposits in the tissue of pigs without any adverse effect.

Doses of orange (Citrus sinensis) essential oil for Nellore steers fed with a forage-based diet

The aim was to evaluate whether the doses of orange essential oil supplementation impact on dry matter intake (DMI), ruminal fermentation parameters, apparent nutrient digestibility, and methane production in Nellore steers fed with forage-based diet. A total of 32 rumen-cannulated Nellore steers (initial BW= 335±25 kg; age= 20±1 month) were assigned to individual pens in a randomized complete block design. Within block, steers were randomly assigned to treatments: CON= diet without orange essential oil (EO); 100EO= CON diet plus 100 mg orange EO/kg DM diet; 200EO= CON diet plus 200 mg orange EO/kg DM diet; and 500EO= CON diet plus 500 mg orange EO/kg DM diet. The main active compounds of the orange EO used were limonene (88.0 %) and myrcene (5.79 %). The experimental period lasted 28d, with 22d for adaptation and 6d for sample collection. From d23 to 27, samples of haylage, concentrate, and total fecal production were collected to determine the total tract apparent nutrient digestibility. Ruminal fluid was obtained from d28 at 0, 6, and 12 h after feeding to determine ruminal fermentation parameters and methane production. The difference was considered significant when P ≤ 0.05. No treatment effects were detected (P>0.05) to DMI or specific nutrient intake. The increasing levels of EO did not affect (P>0.05) the total apparent nutrient digestibility. No treatment effects were detected (P>0.05) for ruminal fermentation parameters in vivo. In ex situ, there was a treatment effect for acetate, total short-chain fatty acids (SCFA), methane, and relative energy loss (REL). For acetate, an increasing linear effect was observed for treatments that received EO for the variables production (g/kg) (P = 0.002) and gross energy (MJ/kg) (P = 0.002), with a higher concentration for the 500EO. For the total production of SCFA, there was an increasing linear effect of treatment with a higher concentration for 500EO for the variables production (g/kg) (P = 0.001) and gross energy (MJ/kg) (P = 0.001). For methane, a quadratic treatment effect was observed for the variables production (g/kg) (P = 0.045) and gross energy (MJ/kg) (P = 0.046), with lower concentrations for the 200EO. There was a decreasing linear treatment effect for REL(%) (P<0.001). The results for the use of orange EO as a manipulator of ruminal fermentation were promising and the dose of 500 mg/kg of DM showed a greater capacity to increase the energy efficiency of fermentation, with greater production of acids and lower production of methane, without affecting the voluntary intake of steers.

The Effects of Papaya Leaf Extract and Turmeric Extract Inclusion on Total Apparent Digestibility of Nutrients and Methane Gas Production in Bali Cattle

This research evaluated the effects of papaya leaf and turmeric extract supplementation on the total apparent digestibility of nutrients and methane gas production in Bali cattle. The livestock used were 18 Bali cattle that were distributed into treatment without papaya leaf and turmeric extract supplementation (P0), Supplementation of 0.0075% turmeric extract g/kg live weight/day (P1), and supplementation of 0.00375% turmeric extract per kg live weight per day + 0.00375% papaya leaf extract per kg live weight per day (P2). The basal diets were 60% elephant grass cv. Taiwan (Pennisetum purpureum cv. Taiwan) and 40% concentrate. The ration provision was three per cent dry matter of body weight. The observed parameters included feed consumption, feces production, dry matter digestibility, organic matter digestibility, crude protein digestibility, crude fat digestibility, crude fibre digestibility, nitrogen-free extract digestibility, and methane gas production. The research results indicated that the treatment did not significantly affect feed consumption (P&gt;0.05) but did affect crude protein digestibility, crude fibre digestibility, nitrogen-free extract digestibility, and methane gas production. This study concludes that the feeding of elephant grass cv. Taiwan (Pennisetum purpureum cv. Taiwan), with the addition of papaya leaf extract and turmeric extract, does not have a positive effect on feed consumption and feed digestibility; thus, it cannot suppress methane gas production in livestock.

Effect of a Bacillus-Based Probiotic on Performance and Nutrient Digestibility When Substituting Soybean Meal with Rapeseed Meal in Grower-Finisher Diets.

The objective of the present study was to test the hypothesis of B. subtilis and B. licheniformis supplementation to a negative control diet in comparison to a standard control diet, had the potential to improve the performance and nutrient digestibility of growing-finishing pigs. For this purpose, 384 fattening pigs of 85 d of age were allotted to three treatments: a standard diet, a negative control (NC) diet (5% soybean meal replaced by 5% rapeseed meal), or a NC diet + probiotic. After reaching a body weight of approximately 110 kg, all animals going to the slaughterhouse (87% of total pigs) were selected to measure carcass quality. Moreover, the apparent total tract digestibility of protein was evaluated at the end of the grower period. The results of this study indicate that supplementation of the tested Bacillus-based probiotic significantly improved average daily gain (ADG, +14.6%) and Feed:gain ratio (F:G, -9.9%) during the grower phase compared to the NC diet. The improvement observed during the grower phase was maintained for the whole fattening period (ADG, +3.9%). Probiotic supplementation significantly improved the total apparent faecal digestibility of dry matter and crude protein in pigs at the end of the grower period. The improvements observed with the additive tested could indicate that supplementation of the Bacillus-based probiotic was able to counteract the lower level of crude protein and standardised ileal digestible amino acids in the NC diet by means of improved protein digestibility.

Doses of lemongrass (Cymbopogon citratus) essential oil for Nellore steers fed with a forage-based diet

The aim was to evaluate whether doses of lemongrass essential oil supplementation affect DMI, apparent nutrient digestibility and methane production in Nellore steers fed forage-based diets. According to their initial fasting BW, 32 Nellore steers (BW = 332±19 kg; age = 19±1 months) rumen cannulated and castrated, were allocated in individual pens in a randomized complete block design. The treatments were randomly assigned to the animals: CON= forage-based diet without addition of lemongrass EO; 200EO= CON diet plus 200 mg/kg lemongrass EO; 400EO= CON diet plus 400 mg/kg lemongrass EO; or 600EO= CON diet plus 600 mg/kg lemongrass EO. The experimental diets contained 95% Tifton-85 haylage and 5% ground corn. The experimental period lasted 21 days, 15 days for diet adaptation and 6 days for sample collection. Samples of haylage, concentrate and total feces production were collected from day 15 to 20, to determine the total apparent digestibility of nutrients. On the 21st day at 0, 6 and 12 h after feeding, rumen fluid was collected to determine the parameters of rumen fermentation and methane production. Significant effects were adopted when P ≤ 0.05. The main active compounds of the EO of lemongrass used were geranial (42.5%) and neral (30.49%). No treatment effects were detected for DM and nutrient intake. The increasing EO levels of lemongrass did not affect the apparent digestibility of nutrients. There was an increasing linear effect (P < 0.05) of treatment in the in vivo analysis, where the highest dose had the highest valerate concentration. There was no effect for any other variables in vivo. Effects on fermentation parameters were identified in the ex situ technique. For acetate, there was a quadratic treatment effect with higher values for the 400EO for the variable production (g/kg day; P = 0.02) and gross energy (Mcal/kg day; P = 0.02). There was linear increase for butyrate production (g/kg day; P = 0.04) and gross energy (Mcal/kg day; P = 0.04). There was a quadratic effect with higher values for the 400EO for production (g/kg day; P = 0.02) and gross energy (Mcal/kg day; P = 0.02) of SCFA. There was a quadratic effect for REL (P = 0.01), with lower loss in the 400EO. There was no treatment effect for propionate (P ≥ 0.97) and methane production (P ≥ 0.19). In conclusion, 400 mg/kg lemongrass EO optimized ruminal fermentation, minimizing energy loss due to methane emissions.

Ensiling Sorghum with Urea, Aerobic Exposure and Effects on Intake, Digestibility, Ingestive Behaviour and Blood Parameters of Feedlot Lambs.

This study was carried out to evaluate the effect of ensiling sorghum silage with urea and amending the aerobic exposure nutrients intake and apparent digestibility, ingestive behaviour and blood serum metabolites of feedlot lambs. Forty uncastrated crossbred Dorper × Santa Inês lambs, aged 150 ± 15 days and with an initial body weight of 21.73 ± 2.40 kg, were used. Animals were assigned in a 2 × 3 factorial arrangement. Thus, six silage diets were produced with various urea addition levels (UA: 0 and 5 g/kg on a natural matter basis) and periods of aerobic exposure of silages (PAE: 0, 24 and 48 h). An effect was observed for nutrient intakes of dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fibre corrected for ash and protein (NDFap) and total digestive nutrients TDN (g/day) and for the total apparent digestibility of DM, OM and CP. There was an interaction effect between urea levels and aerobic exposure for ether extract (EE) and NDFap intakes (g/kg) and nonfibrous carbohydrate (NFC) digestibility (g/kg) (p = 0.012). The addition of 5 g/kg of urea to sorghum ensilage improved the digestibility parameters without changing dry matter intake and ingestive behaviour. The addition or not of urea does not change the blood parameters of the animals.

Effect of Dietary Starch-to-Fat Ratio on Lipid Metabolism, Inflammation, and Microbiota of Multiparous Sow and Newborn Piglets

This experiment aimed to evaluate the effects of dietary starch-to-fat ratio on reproductive performance and lipid metabolism of sows and newborn piglets. A total of 75 Landrace × Yorkshire multiparous sows at d 84 of gestation were selected and randomly divided into three groups based on body weight. From d 85 of gestation to farrowing, sows were fed one of three dietary starch-to-fat ratios (20:1, 10:1, and 5:1). Dietary high starch-to-fat ratio increased the birth weight of piglets (p &lt; 0.05). The apparent total digestibility of dry matter, organic matter, and gross energy of sows was improved by an increasing starch-to-fat ratio during gestation (p &lt; 0.05). Decreased dietary starch-to-fat ratio increased the concentration of plasma triglycerides, total cholesterol, and GSH-Px in sows (p &lt; 0.05). During parturition, sows had increased plasma interleukin (IL) -1β, IL-6, and tumor necrosis factor α in the low ratio group (p &lt; 0.05). The relative abundance of Streptococcaceae in the low ratio group was significantly higher (p &lt; 0.05). The medium dietary starch-to-fat ratio significantly increased the concentrations of short chain fatty acids. In conclusion, this study suggested that for sows a diet with ahigh starch to fat ratio could ameliorate lipid metabolism disorder and maternal inflammation during late gestation.

Different combinations of monensin and narasin on growth performance, carcass traits, and ruminal fermentation characteristics of finishing beef cattle.

The objective of this study was to evaluate the effects of different combinations of monensin and narasin on finishing cattle. In Exp. 1, 40 rumen-cannulated Nellore steers [initial body weight (BW) = 231 ± 3.64 kg] were blocked by initial BW and assigned to one of the five treatments as follows: Control (CON): no feed additive in the basal diet during the entire feeding period; Sodium monensin (MM) at 25 mg/kg dry matter (DM) during the entire feeding period [adaptation (days 1-21) and finishing (days 22-42) periods]; Narasin (NN) at 13 mg/kg DM during the entire feeding period (adaptation and finishing periods); Sodium monensin at 25 mg/kg DM during the adaptation period and narasin at 13 mg/kg DM during the finishing period (MN); and narasin at 13 mg/kg DM during the adaptation period and sodium monensin at 25 mg/kg DM during the finishing period (NM). Steers fed MM had lower dry matter intake (DMI) during the adaptation period compared to NM (P = 0.02) but not compared to CON, MM, MN, or NN (P ≥ 0.12). No differences in DMI were observed among the treatments during the finishing (P = 0.45) or the total feeding period (P = 0.15). Treatments did not affect the nutrient intake (P ≥ 0.51) or the total apparent digestibility of nutrients (P ≥ 0.22). In Exp. 2, 120 Nellore bulls (initial BW = 425 ± 5.4 kg) were used to evaluate the effects of the same treatments of Exp. 1 on growth performance and carcass characteristics of finishing feedlot cattle. Steers fed NM had greater DMI during the adaptation period compared to CON, MM, and MN (P ≤ 0.03), but no differences were observed between NM and NN (P = 0.66) or between CON, MM, and NN (P ≥ 0.11). No other differences between treatments were observed (P ≥ 12). Feeding narasin at 13 mg/kg DM during the adaptation period increases the DMI compared to monensin at 25 mg/kg DM, but the feed additives evaluated herein did not affect the total tract apparent digestibility of nutrients, growth performance, or carcass characteristics of finishing cattle.

Effects of Macleaya cordata extract supplementation on digestive parameters of ponies

ABSTRACT High amounts of grains in the equine diet led to high starch intake, causing gut alterations. Aimed at reducing harmful effects, Macleaya cordata extract (MCE) is a phytogenic additive that stands out for its antibiotic and anti-inflammatory effects proven in different species. However, there is no useful information for horses. The objective of this study was to evaluate the effects of different levels of the inclusion of commercial MCE on body weight (BW), body condition score (BCS), total apparent digestibility (AD) of nutrients, faecal pH and fermentative products, on ponies fed a high-starch diet. Eight healthy gelding Mini Horse ponies were used. The study design was contemporary double Latin-square 4 × 4 in the experimental unit, with the animal inside each experimental period (n = 8 experimental units per group). The experiment was conducted over four 20-d periods. Basal diet attended 1.75% BW dry matter daily and starch intake was 2.2 g/kg BW/meal. The experimental groups were as follows: control – without food additive; S1–1 mg/kg BW MCE; S1.5–1.5 mg/kg BW MCE and S2–2 mg/kg BW MCE. The data were analysed by PROC MIXED of SAS (p < 0.05). Tendency was considered when 0.05 < p < 0.1. Our results showed higher ether extract (EE) AD for S2 group (63.75%) when compared with the control (54.55%) (p = 0.0377). Lactate was lower (p = 0.0391) in S1 (3.27 mmol/l) and S2 (3.24 mmol/l) groups, although pH was not different between groups. Iso-valerate was greater in S1 group (2.29 mmol/l; p = 0.0289), and a tendency of higher butyrate values was found for S1 and S2 groups (p = 0.0980). We concluded that MCE supplementation probably positively influences equine resident microbiota, improving EE AD and increasing iso-valerate concentration. It can also minimise harmful high-starch impact. We recommend further studies using MCE in horses for a better understanding of its local activity and possible benefits.

Reducing dietary sodium of dairy cows fed a low-roughages diet affect intake and feed efficiency, but not yield.

Wastewater from dairy farms has become a major environmental and economical concern. Sodium residue in treated and untreated wastewater from dairy farms used for irrigation can lead to soil and groundwater salinization, with the risk of soil degradation. We examined the effect of reducing sodium fed to mid to late lactating cows from 0.61% (high sodium [HS]) to 0.45% (low sodium [LS]) of dry matter on dry matter intake (DMI), milk and milk-component yields, eating behavior, apparent total track digestibility, feed efficiency, and sodium excretion into the environment. We randomly assigned 28 multiparous high-yielding ( > 35kg milk/d) cows to 1 of 2 treatment groups (LS or HS) in a crossover design, with 7d of adaptation and 28d of data collection. Reducing sodium in the diet reduced sodium intake from 171 to 123g/d while lowering sodium excreted in the manure by 22%. Energy corrected milk (ECM) yield (37.4kg/d) and sodium excretion in the milk (33.7g/d) were similar for both groups. The DMI of LS cows was lower than that of HS cows (27.3 vs. 28kg/d) and consequently, feed efficiency of the LS cows was higher (1.40 vs. 1.35 ECM/DMI). Eating rate, meal and visit frequency, and eating time were similar for both treatments; meal and visit duration were longer for the HS cows, and meal and visit sizes tended to be larger. Digestibility of DM and amylase-treated neutral detergent fiber remained similar. Based on the results of this study, and discussed considerations, we recommend lowering the dietary sodium content for mid to late lactating cows in commercial herds to 0.52% of DM, in order to reduce sodium excretion to the environment via urine.

Potential benefits of a blend of essential oils on metabolism, digestibility, organ development and gene expression of dairy calves

The objective of this study was to evaluate blood cells and metabolites, insulin-like growth factor-1 (IGF-1), digestibility, internal organs weight and histology, gene expression, and spleen cell proliferation of pre-weaned bull calves supplemented with a blend of essential oils in milk replacer (MR). Sixteen newborn Holstein × Gyr crossbred dairy bull calves, with body weight at birth of 33.3 ± 3.7 kg, were housed in individual sand bedded pens, blocked by genetic composition, and randomly assigned to 1 of 2 treatments in a randomized complete block design: Control (CON, n = 8) and blend of essential oils supplementation (BEO, n = 8, 1 g/day/calf, Apex Calf, Adisseo, China). The commercial blend was composed by plant extracts derived from anise, cinnamon, garlic, rosemary, and thyme. Animals were fed 5 L of MR/day reconstituted at 15% (dry matter basis), divided into two equal meals. Water and starter were provided ad libitum. ß-hydroxybutyrate, urea, and glucose were evaluated weekly, IGF-1 was evaluated biweekly, and total blood cell count was performed every four weeks until the end of the trial at eight weeks of age. Feed samples were collected three times a week and polled for weekly analysis. Apparent total nutrient digestibility was determined from d 56 to 60 of age. On d 60 ± 1, animals were euthanized for organ weight, histology, spleen cell proliferation, and intestinal gene expression analysis. Data were analyzed independently using linear mixed models using the REML method in the nlme package in R for continuous outcomes. A non-parametric test was used for ordered categorical outcomes using the Artools package in R. There were no differences between groups for blood evaluations, digestibility, gene expression, and a spleen cell proliferation assay. However, BEO calves presented a heavier pancreas, heavier intestines, bigger ileum villi, and higher cecum butyrate levels (P < 0.05), demonstrating that the EO supplementation helped intestinal development and symbiotic bacteria. It was also observed in CON animals’ heavier respiratory tract and a higher eosinophil count (P < 0.05). Therefore, the organs where eosinophils are more active had a better response for BEO animals. No differences were found in the intestinal gene expression in the immune context. These results demonstrate that supplementing essential oils in MR could contribute to gut development and immune function. However, more research is needed to understand its impact on body development and define the best dosage and route of administration.