A detailed understanding of how dietary carbon (C) is partitioned between excretion, gaseous emissions, and retention is essential for integrating C into current nutrient accounting frameworks, thereby bringing nutrient losses and gas emissions within a single standardized system. To support such integration, the present study aimed to construct C balance models for weaned pigs, grower-finisher pigs, and sows using extant prediction equations and established constants to estimate dietary C input and C outputs via excreta, gas emissions, and retention in body tissues. Predicted C balances showed variable agreement across production stages, with comparatively closer agreement observed in grower-finisher pigs. Estimates of C intake and C output via exhalation were generally consistent with reported values, whereas predictions of fecal, urinary, and enteric CH4 outputs showed greater deviation, indicating areas requiring further refinement. Overall, the models developed in this study offer a conceptual framework for incorporating C into a unified nutrient accounting system. The present study demonstrates the feasibility of combining existing equations to estimate C flows at the animal level, while also highlighting key uncertainties and data gaps that need to be addressed in future research.

Emission of enteric methane from cattle is a challenge for sustainable milk production. Blends of essential oils (EO), as a feed additive, have the potential to reduce enteric methane from cattle. The aim of the present study was to evaluate dairy cow performance, methane emissions and rumen microbiome, when fed a grass-clover silage-based diet supplemented with a blend of EO from the company Agolin SA (AR). Thirty-six Holstein cows were allocated to one of two treatment groups and were fed either a standard TMR diet, or the same diet added 1 g per cow per day of the AR product, which contained 200 mg active blend of EO. The experiment was conducted for a period of 10 weeks in a continuous design plus a pre-period of 1 week. The cows had free access to GreenFeed methane measurement devices throughout the experiment. Individual dry matter intake (DMI), milk yield, milk composition, rumen volatile fatty acids (VFA) were measured. Rumen microbiome was analyzed from metagenomic sequencing of DNA from rumen samples and quantitative PCR targeting total Bacteria, Archaea, Fungi and Protozoa. There was no effect of AR on DMI (P = 0.25), energy-corrected (ECM), milk yield (P = 0.47), or feed efficiency (P = 0.64). Furthermore, there was no significant effect of AR on production of methane per day (P = 0.67), per kg DMI (P = 1.00), or per kg ECM (P = 0.71). In conclusion, adding 200 mg of EO to diets with a high proportion of grass-clover silage had no significant effect on dairy cow performance, methane emissions, rumen fermentation or rumen microbiome.

This study investigated the effects of 25-hydroxycholecalciferol (HyD) supplementation on (1) plasma acute phase reactants, cytokines, and Ig concentrations in colostrum in multiparous Holstein cows from 3 wk prepartum to 21 DIM and (2) plasma concentrations of fat-soluble vitamins, Ig concentrations, minerals, and metabolites of newborn calves. Forty-two cows were assigned to receive either cholecalciferol (D3) or HyD. From 21 d before the expected calving until parturition, the D3 group received 0.475 mg/d (0.035 mg/kg DM) of D3, and the HyD group received 1.45 mg/d (0.108 mg/kg DM) of HyD. From parturition until 21 DIM, the D3 group received 0.625 mg/d (0.024 mg/kg DM) of D3, and the HyD group received 0.625 mg/d (0.024 mg/kg DM) of D3 plus 1.0 mg/d of HyD (0.056 mg/kg DM, equal to 0.080 mg/kg of DM in total). Tail blood samples were collected from cows on d -7 (6 ± 2 d), -3 (2 ± 1 d), 0 (13 ± 8 h postcalving), 1 (36 ± 11 h postcalving), 10 (9 ± 2 d), and 20 (16 ± 2 d) relative to calving for plasma analysis of fat-soluble vitamins (A and E), acute phase proteins (haptoglobin [Hap] and serum amyloid A [SAA]), and cytokines (tumor necrosis-α [TNF-α], IFN-γ, and IL-10). Additionally, a blood sample was taken from a jugular vein of the calves 48 ± 3 (mean ± SD) h after birth. For plasma TNF-α concentration in cows, there was an interaction between treatment and time with lower prepartum concentrations in HyD compared with D3; however, the difference was reduced at calving and reached the same level as D3 group at 20 DIM. No treatment effect was observed for plasma Hap, SAA, IFN-γ, or IL-10. Plasma 25-OH-vitamin D3 (25-OH-D3) concentration of newborn calves in HyD group was higher than in calves from D3 group (13.9 and 8.9 pg/mL, respectively), whereas plasma 25-OH-D2, vitamin A, and vitamin E concentrations were unaffected by the treatment. There was a linear relationship between plasma 25-OH-D3 in calves and in their dams. Colostrum IgA, IgM, and IgG concentrations were not affected by treatment. In line with the colostrum results, plasma IgA, IgM, and IgG of calves were not different between D3 and HyD groups. There was no significant difference in plasma Ca and inorganic P concentrations between D3 and HyD groups in newborn calves. In conclusion, HyD supplementation had limited impact on acute phase reactants and cytokines in transition dairy cows. Dietary supplementation of HyD during the close-up period increased plasma 25-OH-D3 concentrations in the newborn calves without affecting plasma Ca and inorganic P. Additionally, the increased plasma 25-OH-D3 concentrations did not affect Ig concentrations in either colostrum or calf plasma.

Colostrum, the initial milk produced by mammals after giving birth, has evolved to serve as a primary rich source of essential nutrients for newborns. However, there are considerable changes in nutrient composition from colostrum to mature milk. Colostrum and transition milk have specific fat-soluble vitamin levels, fat level, and fatty acid (FA) composition compared to mature milk, and this unique fatty acid composition of colostrum may reflect the physiological needs of newborn calves. The aim of this study was to investigate changes in the FA profile and levels of vitamins A and E from colostrum to mature milk. Colostrum or milk samples from the 1st (colostrum), 2nd, 3rd, 4th, 5th, 6th, and 13th (as a sample of mature milk) milking were collected from 10 multiparous Danish Holstein cows. The level of vitamin A was significantly affected by milking time (p < 0.001), with the highest level in the colostrum (2.3) and the lowest in mature milk (0.5 µg/g). Vitamin E level was significantly affected by milking time (p < 0.001), with the highest level in the colostrum (14.8) and the lowest in mature milk (1.8 µg/g). The proportion of C16:0 FA decreased from colostrum to mature milk while the proportion of C18:0 FA increased from the colostrum to mature milk. The proportion of n-6 FA (C18:2n-6, C18:3n-6, C20:3n-6, C20:4n-6, and C22:5n-6) decreased from colostrum to mature milk (p < 0.001 for all FA). However, the proportion of C18:3n-3 FA increased from colostrum (3.0) to mature milk (5.9 g/kg of FA; p < 0.001), while proportions of C20:5n-3, C22:5n-3, and C22:6n-3 FA decreased from colostrum to mature milk (p < 0.001 for all FA). The proportion of trans 18:1n-10 (p = 0.005) and trans 18:1n-11 (p < 0.001) was affected by milking time and increased from colostrum to mature milk. In conclusion, there is a considerable higher vitamin A and E levels in colostrum compared to mature milk, and vitamin A and E levels were reduced from colostrum to mature milk. Additionally, there were significant changes in the FA profile from colostrum to mature milk, with an increase in C18:3n-3 FA and a decrease in C18:2n-6 FA.

The study aimed to estimate the effect of diet composition, pig production stage, in-housing conditions, and manure management on methane (CH4) emissions from enteric fermentation, manure stored in the barn, and the outdoor storage tank. For each pig category, an estimation for emissions was made for a standard Danish pig diet based on wheat, barley, and soybean meal. Within each category of pigs, emissions were also estimated for diets with different levels and types of dietary fiber from sugar beet pulp, wheat bran, oats, wheat, or soy hulls, which were included as a partial substitution for wheat or barley. In all diets within four pig categories, feed intake, excreted dry matter, feces mass, and urine volume (g/d per animal) increased in sugar beet pulp, wheat bran, oat, or soy hull diets compared to the average Danish diet. In grower-finisher pigs, the sum of CH4 emissions from enteric fermentation, manure stored in the barn, and the outdoor storage tank were 9.8, 10.2, 11.0, 11.0, and 11.2 (kg/year/animal place) for wheat diet, average Danish diet, oat diet, wheat bran diet, and sugar beet pulp diet, respectively, while in gestating sows, were 16.9, 17.5, 18.4, 19.6, 19.7, and 23.2 (kg/year/animal place) in wheat diet, average Danish diet, oat diet, sugar beet pulp diet, wheat bran diet, and soy hull diet, respectively. Contribution of CH4 emissions from manure stored in the barn plus outdoor storage tank for the average Danish diet accounted for 95, 90, 83, and 84% of total CH4 emissions in weaned pigs, grower-finisher pigs, lactating sows, and gestating sows, respectively. In conclusion, feed composition has a considerable impact on CH4 emissions. Enteric CH4 and CH4 emissions from manure stored in the barn and in the outdoor storage tank were increased by elevated concentration of residual fiber in all four pig categories except for enteric CH4 in weaned pigs.

A study evaluated effects of supplementing a barley-corn-soybean meal-based diet with a multi-enzyme product on growth performance and nutrient digestibility of weaned pigs. A total of 122 pigs (initial body weight of 5.2 kg +/- 0.98) were group-housed in 24 pens of 5-6 barrows or 6-7 gilts per pen. Pigs were fed two diets: basal diet without or with a multi-enzyme blend that supplied 4000 U of xylanase, 150 U of beta-glucanase, 1000 U of amylase, and 500 U of protease per kilogram of diet. The diets were fed for 6 weeks in two phases: Phase 1 for the first 3 weeks and Phase 2 for the last 3 weeks. Growth performance was determined by phase, whereas apparent total tract digestibility of nutrients was determined at the end of the experiment. Multi-enzyme did not affect body weight gain, but improved (P < 0.05) gain-to-feed ratio by 5.4% for the entire study period. Multi-enzyme increased (P < 0.05) apparent total tract digestibility of gross energy, neutral detergent fiber, and acid detergent fiber by 2.7%, 20.7%, and 41.9%, respectively. In conclusion, the test multi-enzyme product can improve feed efficiency of weaned pigs, likely through improved digestibility of dietary fiber components.

High-yielding dairy cows around parturition are challenged by varying degrees of low calcium status (hypocalcemia), which is associated with increased risk of several metabolic disorders and diseases in early lactation. The aim of the present study was to investigate effects of dietary 25-hydroxycholecalciferol (25-OH-D3; calcidiol) supplementation during the transition period. Forty-two multiparous Holstein cows were fed 1 of 2 treatments: either cholecalciferol (D3) or 25-OH-D3 (HyD) as dietary vitamin D supplements. From 21 d before the expected calving until parturition, the D3 group received 0.475 mg/d (0.035 mg/kg of DM) of D3, and the HyD group received 1.45 mg/d (0.108 mg/kg of DM) of 25-OH-D3. From parturition until 21 DIM, the D3 group received 0.625 mg/d (0.024 mg/kg of DM) of D3, and the HyD group received 0.625 mg/d (0.024 mg/kg of DM) of D3 plus 1.0 mg/d of 25-OH-D3 (0.056 mg/kg of DM). Arterial blood samples were collected by puncture of a. auricularis on d -21, -7, -3, 0 (calving day), and +1 relative to calving for analysis of blood ionized Ca. Blood samples were taken from the tail on d -21 (22 ± 5 d), -7 (6 ± 2 d), -3 (2 ± 1 d), 0 (d 0; 13 ± 8 h after calving), 1 (36 ± 11 h after calving), 10 (9 ± 2 d), and 20 (16 ± 2) relative to calving to analyze plasma 25-OH-D3 level, plasma minerals, and other plasma metabolites. During the entire experiment, cows were fed TMR, and DMI, productive performance, metabolic disorders, and other diseases were recorded. Milk yield, milk protein percentage, milk lactose percentage, BCS, and BW were not affected by treatment. There was an interaction between treatment and time for DMI. The DMI in HyD was numerically lower compared with D3 at d -3, -2, and -1 relative to calving; however, the DMI in HyD was numerically higher compared with D3 at d 0, 1, and 2 postpartum. Plasma 25-OH-D3 was higher in HyD compared with D3 both pre- and postpartum; however, plasma 1,25(OH)2D3 was not affected by treatment. Arterial blood ionized Ca was affected by treatment, and it was higher in the HyD (1.08 ± 0.02) compared with the D3 on the day of calving (0.99 ± 0.02 mmoL/L; lsmeans ± SEM). There was a tendency for lower incidence of mastitis in HyD compared with D3. Plasma BHB level (lsmeans ± SEM) was significantly lower in HyD (0.61 ± 0.02) compared with D3 (0.70 ± 0.02 mM). In conclusion, feeding 25-OH-D3 to transition dairy cows increased arterial blood ionized Ca on the day of calving compared with cows supplemented with D3. The increased arterial blood ionized Ca in HyD was apparently mediated by 25-OH-D3 without affecting plasma 1,25-(OH)2D3. Additionally, the results showed a lower incidence of mastitis in HyD.

Energy and nutrient availability in corn DDGS for pigs is partly limited by complex interactions between fiber and protein of the corn DDGS. Supplemental direct fed microbials (DFM) and protease can potentially improve energy and nutrient availability in corn DDGS-based diets for pigs. This study determined the effects of supplementing a corn DDGS-soybean meal (SBM)-based diet with a combination of protease and Bacillus-based DFMs on the growth performance and apparent total tract digestibility (ATTD) of nutrients in pigs. Eighty pigs (initial BW = 29.2 kg) housed in 20 pens were fed two diets (10 pens per diet), which were a corn DDGS-SBM-based diet without or with a combination of Bacillus subtilis protease at 5,000 U/kg and three-strain Bacillus-based DFMs at 1.5 × 105 CFU/g. The basal diet contained phytase at 750 FTU/kg and was formulated to meet the nutrient recommendations for grower–finisher pigs except for NE, Ca, and P contents, which were lower than the recommendations by 0.209 MJ/kg, 0.9 g/kg, and 0.9 g/kg, respectively. The diets were fed in three phases based on BW: phase 1 from 30 to 55 kg, phase 2 from 55 to 75 kg, and phase 3 from 75 to 100 kg. Growth performance was determined by phase, whereas the ATTD of nutrients was determined at the end of phase 1. Protease and DFM supplementation increased (P < 0.05) the ATTD of gross energy, nitrogen, and P by 8.0%, 10.3%, and 15.5%, respectively, but did not affect BW gain and feed intake. In conclusion, adding protease and DFMs to the corn-DDGS-SBM-based diet increased nutrient digestibility but did not affect the growth performance of pigs, implying that the basal diet was not deficient in energy. Thus, basal diets with appropriate low energy values should be developed to optimize the utilization of protease and DFMs in diets for pigs.

Methanogenesis inhibition in vivo is often associated with higher dihydrogen (H2) emission without an increase in production efficiency. The objectives of this in vitro study were to test the effects of the addition of iodoform (IOD; 0.007% w/w on DM basis) and quercetin (QUE; 3%) as CH4-inhibitors, and activated charcoal powder (ACP; 3%), phloroglucinol (PHL; 5%), and vitamin E (VitE; 0.45%) as H2-acceptors on CH4 and H2 productions and rumen fermentation. The additives were tested alone, as combination of each CH4-inhibitor with a H2-acceptor, or as combination of both CH4-inhibitors with each H2-acceptor against the basal feed without additives (CTR). Fermentations lasted 48 h, total gas production was determined by AnkomRF system equipped with gasbags. Gas samples were taken at 24 h to analyse the production of CH4 and H2. After 48 h, pH and concentrations of volatile fatty acids (VFA) and ammonia were determined. Compared to CTR, IOD reduced CH4 production (mL/g DM) by 62.0% and increased H2 production, while QUE induced a not significant -19.3% without affecting H2 production. All the H2-acceptors failed to reduce H2 production when tested in combination with the CH4-inhibitors. Phloroglucinol increased VFA concentration without affecting CH4 production, ACP acted as IOD antagonist, while VitE had no impact on almost all the parameters considered when incubated alone or in combination with the CH4-inhibitors. Finally, a synergistic effect was observed with the combined use of IOD and QUE, which significantly reduced CH4 production (-97.6% vs CTR), minimising the H2 increase without negative effects on VFA concentration.

The effect of heat treatment (raw or micronization) and vitamin E supplementation (0 or 200 mg/kg DM of RRR-alpha-tocopherol) on ruminal biohydrogenation (BH) kinetic of whole flaked rapeseed was studied using in vitro batch culture in a 2 x 2 factorial design. Experimental treatments were: whole flaked raw rapeseed without vitamin E (RR0), whole flaked raw rapeseed supplemented with 200 mg/kg DM of vitamin E (RR200), micronized whole flaked rapeseed without vitamin E (MR0) and micronized whole flaked rapeseed supplemented with 200 mg/kg DM of vitamin E (MR200). The disappearance of linoleic acid (LA), alpha-linolenic acid (LnA), oleic acid (OA), and appearance of stearic acid (SA), and C18:1 trans-11 (VA) were significantly decreased by micronization (P < 0.0001 for all). The appearance of cis-9, trans-11 conjugated linoleic acid (CLA; P < 0.0001) and C18:1 trans-10 (P = 0.01) was significantly increased by micronization. Biohydrogenation of LA (P = 0.03) and OA (P = 0.02) was significantly decreased by vitamin E. There was a tendency to reduce disappearance of LnA by vitamin E (P = 0.06). In conclusion, micronization is an effective method to protect unsaturated fatty acids (UFA) from ruminal BH. Vitamin E supplementation can be an advantageous strategy to decrease LA, LnA and OA biohydrogenation.

In postweaning calves, it is a challenge to maintain the plasma vitamin E level at or above the recommended level (3 µg/mL), which is linked to a good immune response. It has been unclear until now why the provision of solid feed with concentrations below 200 mg/kg feed of vitamin E is ineffective in maintaining the plasma vitamin E level of calves above the recommended plasma level postweaning. The present study was conducted to investigate if a high fat to vitamin E ratio in the concentrate could protect and improve the delivery of the natural form of vitamin E (RRR-α-tocopherol) to calves postweaning. Thirty calves were included in the experiment from 2 weeks preweaning until 2 weeks postweaning (Weeks -2, -1, 0 [weaning], 1, and 2 relative to weaning) and fed one of three concentrates in which lecithin mixture provided the fat supplement: control (77 mg/kg of vitamin E and 4.9% DM of crude fat; CONT), medium level of vitamin E supplemented (147 mg/kg of vitamin E and 7.7% DM of crude fat; MedVE) or high level of vitamin E supplemented (238 mg/kg of vitamin E and 12.4% DM of fat; HiVE). Thus, there was a comparable ratio of fat to vitamin E (520-630) in the three concentrates. During the 2 weeks postweaning, final body weight (92 ± 2 kg), average daily gain (917 ± 51 g/day) and concentrate intake (2.2 ± 0.09 kg/day; mean of treatment ± standard error) were unaffected by treatment and the interaction between treatment and week. There was an interaction between treatment and week for vitamin E intake pre- (p < 0.001) and postweaning (p < 0.001). There was an interaction between treatment and week (p < 0.001) for plasma vitamin E level postweaning, and it was 2.5, 3.1, and 3.8 µg/mL in CONT, MedVE, and HiVE, respectively, at Week 1 postweaning. In addition, plasma vitamin E levels at Week 2 postweaning were 2.6, 3.6 and 4.8 µg/mL in CONT, MidVE and HiVE respectively. The results show that 147 mg/kg of lecithin-protected vitamin E in the concentrate is needed to secure a plasma vitamin E level well above the recommended level. In addition, lecithin-protected vitamin E elevated the plasma level of triglycerides and nonesterified fatty acids.

The most critical challenge in early lactation is to meet the increasing energy demand for milk production, which results in a negative energy balance (EB). The objective of this study was to evaluate the productive performance and plasma metabolite responses of early lactating dairy cows fed diets supplemented with increasing levels of different fat sources. Diets were categorized as diets supplemented with saturated fatty acid rich fat sources (SFAR), with Ca-soaps of fatty acids (CaFA), and with polyunsaturated fatty acid rich fat sources (PUFAR). There was an interaction between crude fat level and source for dry matter intake (DMI); each percentage-unit increase reduced DMI by 0.38 and 0.77 kg/d in CaFA and PUFAR, respectively, and increased DMI by 0.55 kg/d in SFAR. Corrected milk yield increased by 0.44 kg/d for each percentage-unit increase in crude fat level. Plasma non-esterified fatty acid (NEFA) concentration increased with 0.04 mmol/L per percentage-unit increase. In conclusion, the increased crude fat level increased corrected milk yield. Fat supplementation in early lactation does not seem to cause negative effects on productive performance or metabolism, and despite a small increase, both plasma NEFA and beta-hydroxybutyrate (BHB) concentrations stayed below the threshold for incidence of subclinical ketosis.

Milk production and milk fatty acid (FA) composition were followed in three Danish commercial organic dairy farms where grass clover silage was substituted with a forb-rich silage. Farms A, B, and C included a total of 50, 189, and 235 lactating dairy cows, and 20 cows in each herd were selected to record the productive performance and milk composition. In all farms, 70% of diets were grass clover silage, and during the experiment, forb-rich silage gradually replaced grass clover silage during the 2-4 weeks, where after cows were fed the forb-rich silage diets for additional 2 weeks. The data were separately analyzed in each farm. Milk production at farms A and B was not affected by diet change, but milk production at farm C decreased by 1.7 kg energy corrected milk (ECM)/cow in cows fed the forb-rich silage. Regardless of farm, the proportion of C18:3n-3, C18:2n-6, and conjugated linoleic acid (CLA) isomers in milk from cows receiving the forb-rich silage increased compared to cows fed grass clover silage based diets. The results indicate the possibility for further increase in the content of poly-unsaturated fatty acids (PUFA) in organic milk by substituting grass clover silage with forb-rich silage.

High-starch diets may affect equine hindgut microbiota and increase blood glucose levels, which may cause unwanted physiological changes, but may also elicit behavioural changes such as increased fear reactions. The purpose of the current study was to feed a high starch (300) and low fat (43; HS_LF) or a low starch (60) and high fat (85; LS_HF, g/kg of DM) concentrate within the available commercial range and investigate how muscle endurance and fear reactions of horses respond to different diets. Twenty Danish Warmblood stallions (4 years) were randomly allocated to two treatments: LS_HF (n = 10) and HS_LF (n = 10) for 9 weeks. During the two last weeks, a single step exercise test was performed, and plasma metabolites and blood gases were measured before and after exercise in a 2 × 2 factorial design. The effect of two diets on fearfulness was tested by exposing the horses to novel objects test (T1 and T2). Plasma metabolites was not affected by diets. However, plasma level of glucose post-exercise (4.9) was lower than pre-exercise (5.6 mmol/L; p < 0.001). Similarly, plasma level of insulin post-exercise (4.2) was lower than pre-exercise (13.1 pmol/L; p < 0.001). Plasma level of lactate dehydrogenase (p < 0.001), non-esterified fatty acids (p = 0.002), β-hydroxybutyrate (p = 0.001), and fructosamine (p = 0.01) post-exercise was higher than pre-exercise. Regardless of type of diets, RRR-α-tocopherol was the dominance α-tocopherol stereoisomers in plasma. In conclusion, during aerobic exercise, fat to starch ratio in horse diets within the normal range had no significant effect on plasma metabolites. However, horses fed LS_HF tended to show more investigative behaviour than horses fed HS_LF.

Piglet survival is a major challenge in the first few days postpartum and interventions during this period may improve survival and growth. This study investigated the effects of palmitoleic acid (C16:1n-7; PA) supplementation on growth performance, body temperature, fatty acid (FA), and energy metabolism in milk-replacer-fed piglets. Forty-eight piglets were stratified by body weight and randomly assigned to one of four dietary treatments (0%, 1%, 2%, and 3% PA supplementation as a percent of milk replacer) and given the diet through an orogastric tube. They were fed dietary treatments every 2 h for 4 d in the first week postpartum and all were sacrificed at the end of the experiment. The piglets were weighed daily, and half in each dietary treatment group, the same piglets each day, were exposed daily to a lower temperature for 2 h. Plasma samples were collected immediately before sacrifice for analyses of FA and other plasma metabolites. The weight of organs and empty body weight were determined after sacrifice. Liver and semimembranosus muscle tissue samples were collected and analyzed for FA content. Contents of C16:1n-7 and C18:1n-7 in both plasma and liver (P < 0.001), and C16:1n-7 in semimembranosus muscle (P < 0.001) increased linearly as PA supplementation increased. Most plasma FA levels (except C16:1n-7, C16:1n-9, and C22:5n-3) were lower in piglets exposed to lower temperatures than those that were not. Plasma glucose, triglycerides, and lactate dehydrogenase levels increased linearly with PA supplementation (P < 0.001). Piglets' average daily gain, liver glycogen pool, liver weight, and gallbladder weight increased linearly (P < 0.05, P < 0.01, P < 0.05, and P < 0.001, respectively), but lung weight, liver nitrogen content, and body temperature drop decreased linearly (P < 0.01, P < 0.001, and P < 0.05, respectively) with PA supplementation. Piglets exposed to low temperature had greater liver nitrogen (P < 0.05) and lactate dehydrogenase (P < 0.001) contents but had lower liver weight (P < 0.01) and plasma lactate concentration (P < 0.05) than those that were not. In conclusion, this study demonstrated the importance of PA on the growth performance of the piglets by increasing their average daily gain and decreasing a drop in body temperature upon cold exposure, most likely due to a modified energy metabolism.

The accurate estimation of in vitro ruminal biohydrogenation (BH) kinetics of fatty acids (FA) allows for a more accurate understanding of their dynamics and develop targeted strategies to enhance desirable FA bypass. This study comprises a comprehensive evaluation of 33 nonlinear regression models to determine the most suitable model for accurately estimating the in vitro BH kinetics of individual FA. The data set utilized in the present research originates from a recent investigation on the effects of micronization and vitamin E on the in vitro ruminal BH of rapeseed. For the nonlinear regression analysis, data comprising FA concentrations (expressed as g FA/100 g FA) at the conclusion of 2, 4, 8, 12, 24, and 48 h incubation periods were employed. The evaluation of nonlinear regression models focused on identifying the ideal model based on criteria including the highest R2 value, the lowest RMSE value, and statistically significant coefficients. The results pinpoint the Gompertz model as an effective choice for estimating the in vitro ruminal BH kinetics of upward-trending fatty acids, including intermediate unsaturated fatty acids and saturated end FA. Additionally, the first-order kinetic model of Ørskov and McDonald emerges as the preferred model for investigating the BH kinetics of downward-trending fatty acids, including oleic acid, linoleic acid, and alpha-linolenic acid. In summary, this rigorous evaluation led to the identification of the most appropriate model, one that not only exhibited an exceptional fit to the data but also provided profound insights into the intricate relationships between predictors and the dynamic behavior of FA. The established nonlinear regression models will serve as invaluable tools for future research investigating FA biohydrogenation kinetics.

Abstract Background Survival of piglets poses a significant challenge in the initial days after birth because piglets are lacking readily oxidizable brown adipose tissue and born with limited amount of body reserves, which in turn limited theirthermogenic capacity. This study investigated the effects of palmitoleic acid (PA) supplementation on growth performance, maintenance of body temperature, muscle fatty acid (FA) compositions, and energy metabolism in milk replacer fed piglets. Forty-eight piglets were stratified by body weight and randomly assigned to one of four dietary treatments (0%, 1%, 2%, and 3% PA supplementation as percent of milk replacer). Piglets were weighed daily, and half in each dietary treatment groups were exposed daily to low temperature for 2 h. Plasma and tissue samples were collected at the end of the experiment for further analyses. Results Contents of C16:1n-7 and C18:1n-7 in both plasma and liver (P < 0.001), and C16:1n-7 (P < 0.001) in semimembranosus increased linearly as PA levels increased. Most plasma FA levels (except C16:1n-7, C16:1n-9 and C22:5n-3) were lower in piglets exposed to low temperature than those that were not. Plasma glucose, triglycerides and lactate dehydrogenase levels increased linearly with PA supplementation (P< 0.001). Piglets’ average daily gain, liver weight, liver glycogen pools, and gallbladder increased linearly with PA supplementation (P < 0.05, P < 0.01, P < 0.05, and P < 0.001, respectively), but lung weight, liver nitrogen content, and body temperature drop at cold exposure decreased linearly with PA supplementation (P < 0.01, P < 0.001, and P < 0.05, respectively). Piglets exposed to low temperature had greater liver nitrogen (P < 0.05) and lactate dehydrogenase (P < 0.001) contents, but had lower liver weight (P < 0.01) and plasma lactate concentration (P< 0.05) than those that were not. Conclusion Dietary supplementation of PA increased C16:1n-7 concentrations in plasma, liver, and semimembranosus as well as average daily gain of the piglets. The drop in body temperature of the piglet upon cold exposure decreased linearly with increasing PA supplementation.

This study evaluated the effects of including soluble and insoluble dietary fiber sources in soybean oil-containing diet for broiler chickens on coefficient of apparent ileal digestibility (AID) of amino acids, coefficient of apparent retention (AR) of nutrients, and nitrogen-corrected apparent metabolizable energy (AMEn). A total of 180 broilers were divided into 30 groups and fed 3 diets from day 14 to 21 of age. The diets were corn–soybean meal containing 6.8% soybean oil without or with soybean hulls (SBH) or sugar beet pulp (SBP) at 8.0% as sources of insoluble and soluble fiber, respectively. The SBH and SBP contained 6.0% and 14.7% of soluble dietary fiber and 60.5% and 37.0% of insoluble dietary fiber, respectively. The AID of indispensable amino acids was decreased ( P < 0.05) due to dietary inclusion of SBH, but not of SBP. Dietary SBH and SBP reduced the AR of gross energy (by 14% and 8%, respectively) and AMEn (by 20% and 14%, respectively). Overall, inclusion of SBH or SBP at 8.0% in a corn–soybean meal-based diet for broilers that contains high level of soybean oil might not improve nutrient digestibility. However, SBP has less detrimental effects on nutrient digestibility than SBH.