The objective was to investigate the effect of rainfall on sodium (Na) dissolution and total losses by runoff of loose mineral mixtures (MM) available in uncovered feeders to grazing cattle, as well as the possible impacts on their growth performance and fulfilment of Na nutritional needs. Experiments (n = 7) were conducted to quantify the amount of Na lost due to rainfall and to evaluate the effects of different Na levels in the MM (35, 70, 105, and 140 g Na/kg) on MM assumed intake and growth performance. Cattle grazed Brachiaria sp. pastures and received free-choice MM in uncovered feeders throughout four to nine evaluation periods lasting 14 to 21 d each. MM assumed intake from the feeder was measured in each period as the difference between the supplied MM mass and the unconsumed MM mass. A new methodology was proposed to measure MM losses by runoff (exclusion feeder). The mass of runoff MM and the volume of runoff rainwater were both determined and analysed for their mineral content. The dietary Na requirement was estimated using different feeding systems. The minimum MM Na content to meet dietary Na requirements was estimated in different scenarios. Sodium chloride composed 28% of the runoff MM mass, in average. The action of rain may reduce MM Na content by 28% in a single rainfall event. Na content strongly affected MM assumed intake and, possibly, growth rate. MM losses by runoff were estimated at 25.5%, according to the exclusion feeder methodology. The minimum required MM Na content for meeting dietary Na needs may reach up to 87.3 g Na/kg. About 27% of evaluated periods may have failed to fully meet cattle Na requirements. The action of rain in unsheltered loos MM may result in unbalanced mineral consumption and unmet Na needs, leading to impaired mineral nutrition of grazing cattle, especially in tropical conditions.
Hemp (Cannabis sativa L.) is an important source of fibre and seed oil and protein. By-products of industrial hemp fibre production, like hemp seeds and cakes, can be used as feed for all animal species as fat and protein source and the whole hemp plant (including stalk and leaves) might be a suitable fibre source for ruminants. However, a previous feeding experiment with leaf-flower-seed hemp silage, made from an industrial hemp variety, demonstrated detrimental effects on cow health parameters and a significant transfer of several cannabinoids, including the psychoactive tetrahydrocannabinol (∆9-THC), into cow's milk, posing a potential risk to the safety of consumers. Based on those observations, the present study tested the hypothesis that anaerobic fermentation, as during ensiling, increases the content of ∆9-THC in hemp. Therefore, silages of whole plants from the industrial hemp Cannabis sativa L. var. Ivory were prepared in a multifactorial design, with the four treatments 1) untreated control (CON), 2) addition of 10 mL per kg fresh weight homofermentative lactobacilli at 105 cfu/mL (LBAC), 3) addition of 10 mL per kg fresh weight homofermentative lactobacilli at 105 cfu/mL plus 30 g molasses (LBACmol) and 4) addition of propionic acid (10 mL/kg fresh weight) (PRO). Ultra high performance liquid chromatography coupled with tandem mass spectrometry with electrospray ionisation (UHPLC-MS/MS) was performed for analysis of cannabinoids in fresh hemp material and after 10 and 90 days of ensiling. The study revealed that ensiling decreased all acid forms of analysed cannabinoids in hemp at about 40-65% of the initial values after 90 days of storage, with the exception of cannabinolic acid (CBNA), and CBGA, the acidic form of cannabigerol (CBG). This decrease in most acidic forms was accompanied by an increase of the corresponding non-acidic forms of all cannabinoids, including the psychoactive ∆9-THC. Thus, although ensiling decreases the total cannabinoid content, psychoactive compounds like ∆9-THC can increase, enhancing the risk for animal health and a transfer of these substances into animal derived products. Industrial hemp can be ensiled with different additives, despite its high buffering capacityUltra high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) was used for analysis of cannabinoidsEnsiling decreased total cannabinoid content in industrial hemp, but increased individual compounds like ∆9-THC, likely through decarboxylation of the precursor ∆9-THCA.
Meat is highly susceptible to oxidation, which leads to the degradation of lipids and proteins, resulting in undesirable changes in meat quality, such as colour and shelf life. This process can be mitigated by both non-enzymatic antioxidants and enzymatic antioxidants, including superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). The oxidative stability of meat is influenced by several factors, including animal nutrition. The aim of this study was to assess the impact of corn silage supplementation on meat oxidative status and its correlation with the expression level of genes associated with this process in the longissimus thoracis et lumborum muscle of Braford steers. For this study, 30 steers were randomly assigned to two experimental groups of 15 animals each. One group was fed with ad libitum pasture supplemented with corn silage and the other group was fed with ad libitum pasture. The degree of protein and lipid oxidation was determined by total protein carbonyl content and lipid degradation products, respectively. The antioxidant capacity was determined by measuring the radical-scavenging activities, total phenol content (TPC), and the activities of the CAT, SOD, and GPx enzymes. In addition, the relative levels of sod (1 and 2), cat, and gpx genes were evaluated using real-time polymerase chain reaction. The results indicated that meat from corn-silage supplementation exhibited higher levels of oxidation than those from pasture-fed steers. Also, results showed that meat from corn-silage-supplemented steers were more oxidised than those from pasture-fed steers. Moreover, hydrophilic extracts showed higher levels of antioxidant capacity than liphophilic ones in boths feeding systems and the muscles of animals that received corn exhibited a 17% reduction in TPC. In addition, expression levels of cat, sod (1 and 2), and gpx genes were lower in this group compared to the pasture-finished group. Consequently, the gene expression of the antioxidant enzymes exhibited a negative correlation with lipid oxidation, and with lipophilic antioxidants. Conversely, a positive correlation was observed with polyphenol content. This study demonstrated that the oxidative stability of meat can be enhanced by feeding steers with pasture, rather than finishing with corn silage supplementation. Moreover, attributable to reduced expression levels of antioxidant enzymes, leading to higher lipid and protein oxidation levels, which has a deleterious effect on meat quality. Consequently, the gene expression of the antioxidant enzymes evaluated, specifically sod, cat and gpx, has been identified as a promising reliable biomarker for oxidative stability in meat.
Lower respiratory infections (LRIs) remain the world's leading infectious cause of death. This analysis from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2023 provides global, regional, and national estimates of LRI incidence, mortality, and disability-adjusted life-years (DALYs), with attribution to 26 pathogens, including 11 newly modelled pathogens, across 204 countries and territories from 1990 to 2023. With new data and revised modelling techniques, these estimates serve as an update and expansion to GBD 2021. Through these estimates, we also aimed to assess progress towards the 2025 Global Action Plan for the Prevention and Control of Pneumonia and Diarrhoea (GAPPD) target for pneumonia mortality in children younger than 5 years. Mortality from LRIs, defined as physician-diagnosed pneumonia or bronchiolitis, was estimated using the Cause of Death Ensemble model with data from vital registration, verbal autopsy, surveillance, and minimally invasive tissue sampling. The Bayesian meta-regression tool DisMod-MR 2.1 was used to model overall morbidity due to LRIs. DALYs were calculated as the sum of years of life lost (YLLs) and years lived with disability (YLDs) for all locations, years, age groups, and sexes. We modelled pathogen-specific case-fatality ratios (CFRs) for each age group and location using splined binomial regression to create internally consistent estimates of incidence and mortality proportions attributable to viral, fungal, parasitic, and bacterial pathogens. Progress was assessed towards the GAPPD target of less than three deaths from pneumonia per 1000 livebirths, which is roughly equivalent to a mortality rate of less than 60 deaths per 100 000 children younger than 5 years. In 2023, LRIs were responsible for 2·50 million (95% uncertainty interval [UI] 2·24-2·81) deaths and 98·7 million (87·7-112) DALYs, with children younger than 5 years and adults aged 70 years and older carrying the highest burden. LRI mortality in children younger than 5 years fell by 33·4% (10·4-47·4) since 2010, with a global mortality rate of 94·8 (75·6-116·4) per 100 000 person-years in 2023. Among adults aged 70 years and older, the burden remained substantial with only marginal declines since 2010. A mortality rate of less than 60 deaths per 100 000 for children younger than 5 years was met by 129 of the 204 modelled countries in 2023. At a super-regional level, sub-Saharan Africa had an aggregate mortality rate in children younger than 5 years (hereafter referred to as under-5 mortality rate) furthest from the GAPPD target. Streptococcus pneumoniae continued to account for the largest number of LRI deaths globally (634 000 [95% UI 565 000-721 000] deaths or 25·3% [24·5-26·1] of all LRI deaths), followed by Staphylococcus aureus (271 000 [243 000-298 000] deaths or 10·9% [10·3-11·3]), and Klebsiella pneumoniae (228 000 [204 000-261 000] deaths or 9·1% [8·8-9·5]). Among pathogens newly modelled in this study, non-tuberculous mycobacteria (responsible for 177 000 [95% UI 155 000-201 000] deaths) and Aspergillus spp (responsible for 67 800 [59 900-75 900] deaths) emerged as important contributors. Altogether, the 11 newly modelled pathogens accounted for approximately 22% of LRI deaths. This comprehensive analysis underscores both the gains achieved through vaccination and the challenges that remain in controlling the LRI burden globally. Furthermore, it demonstrates persistent disparities in disease burden, with the highest mortality rates concentrated in countries in sub-Saharan Africa. Globally, as well as in these high-burden locations, the under-5 LRI mortality rate remains well above the GAPPD target. Progress towards this target requires equitable access to vaccines and preventive therapies-including newer interventions such as respiratory syncytial virus monoclonal antibodies-and health systems capable of early diagnosis and treatment. Expanding surveillance of emerging pathogens, strengthening adult immunisation programmes, and combating vaccine hesitancy are also crucial. As the global population ages, the dual challenge of sustaining gains in child survival while addressing the rising vulnerability in older adults will shape future pneumonia control strategies. Gates Foundation.
This study aimed to evaluate the effect of dietary copper (Cu) and zinc (Zn) levels and xylanase and protease supplementation on apparent digestibility of nutrients at the end of the ileum (AID) and large intestine (ALID). Using a 2 × 2 factorial design, 24 weaned pigs were assigned to one of the four barley-wheat-soybean meal diets, supplemented with two levels of Cu/Zn (20/125 and 40/250 mg/kg) and either a mix of xylanase and protease (ENZ) or no enzyme supplementation. Neither the Cu/Zn level nor ENZ affected AID of nutrients. However, ALID of dry matter and fibres (ADF and NDF) increased with ENZ supplementation (p < 0.010). Enzyme supplementation also influenced the ALID of crude protein and phosphorus, depending on the Cu/Zn levels (Mineral × ENZ, p < 0.050). Specifically, ENZ increased the ALID of crude protein in the high Cu/Zn diet, while ALID of phosphorus increased by 63% with ENZ in low Cu/Zn diet but only by 23% in the high Cu/Zn diet. The high Cu/Zn level increased the ALID of dry matter but had no effect on the ALID of other nutrients. In conclusion, ENZ supplement increased the apparent digestibility of nutritional compounds, but this effect was dependent on the level of Cu/Zn in the diet. Further research is needed to explore the interaction between xylanase/protease and nutritional components of feed to maximise the benefits of these supplements.
Biomass from cultivated edible mushrooms can be sustainably produced using residual lignocellulosic sidestreams from agri-industrial and wood processing and is a rich source of a variety of bioactive compounds. While edible mushrooms have a long history as a tasty and healthy food for humans, the potential of mushrooms (fungal fruiting bodies), fungal mycelia and by-products from mushroom production (stem residues, spent mushroom substrate) as feed component for poultry is less acknowledged. Based on this, the present review aims to describe the role of filamentous fungi in circular feed production, characterise the nutritional value of fungal biomass, and provide up to date evidence about the efficacy of feeding fungal biomass on performance of broilers. Feeding studies with healthy and parasite-infected broilers using fungal fruiting bodies, mycelia, stem residues or spent mushroom substrate nearly equally showed either positive or neutral effects on growth performance, whereas impairments of performance and carcass parameters were not reported. Improvements of broiler performance in response to feeding fungal biomass were at least partially associated with a beneficial modulation of the gut microbiota community structure - effects that are most likely attributed to the presence of fermentable polysaccharides and phenolic compounds with prebiotic and selective antimicrobial activities, respectively. Based on the evidence from literature presented in this review, the inclusion of fungal biomass, particularly inexpensive by-products from mushroom production like stem residues and spent mushroom substrate, in broiler diets can be recommended, because even if no growth-promoting effects are induced the partial replacement of less sustainably produced feed components by fungal biomass improves the environmental impact of broiler production. Considering that the number of broiler studies showing either positive or neutral effects of fungal biomass on growth performance is broadly balanced and divergent study outcomes are reported even for biomass from the same fungal species, future studies are necessary to identify the specific requirements of fungal biomass responsible for promoting broiler performance.
A study was conducted to investigate the chemical composition and feeding value of rapeseed meal (RSM) batches produced at the same plant when fed to turkey poults. In total, seven RSM samples were obtained from a single manufacturer within a period of 90 days. Although the manufacturer followed the same procedures during oil extraction and RSM production, different batches of rapeseed were used. A balancer feed (BF) was formulated to contain 11.85 MJ/kg ME and 265 g/kg crude protein. Seven nutritionally complete test mash diets were prepared by mixing 200 g/kg of each RSM batch sample with 800 g/kg of the BF, totalling 8 diets. Diets were fed to female B.U.T. Premium turkeys from 12 to 21 d of age. Each diet was fed to six raised floor pens, housing two birds, following randomisation. During the experiment, a nitrogen corrected apparent metabolisable energy (AMEn) assay was performed using a total collection technique. The AMEn in RSM samples was calculated based on the differences between the AMEn values of basal and test diets. Associations were examined between AMEn and the chemical composition of the RSM samples. The overall determined AMEn value of the RSM ranged from 5.50 MJ/kg DM to 8.53 MJ/kg DM, giving an average AMEn of 7.29 MJ/kg DM. There was no difference (p > 0.05) in AMEn content between batches. There was a negative correlation (r = - 0.864; p < 0.05) between AMEn values and the neutral detergent fibre (NDF) content of the RSM samples. The results suggest that the NDF could be a good predictor of the AMEn of industry produced RSM. It may be inferred that processing rather than cultivar could be the main factor determining the feeding value of RSM for turkeys.
The present study aimed to assess the dynamics of rumen methane (CH4) production following the addition of NaNO3. This was done using an in vitro rumen fermentation system that ensures continuous gas and methane assessments. Four different levels of NaNO3 were used to get the final nitrate concentrations of 0.5, 1.0, 1.5, and 2.0 mg/ml of rumen fluid. For each dose, corresponding controls contained sodium chloride and urea were realised to ensure comparable levels of sodium and nitrogen. The addition of nitrates had slight effect on the intensity of fermentation because the total gas produced minus CH4 (total methane-free gas) only went down at the highest dose (2.0 mg/ml), and the final concentrations of SCFA were the same at all doses. The most evident effect was a modification of the SCFA profile (low concentrations of propionate and valerate, progressive increments of acetate, and decreases of butyrate) and a reduction in overall CH4 production. The CH4 yield for the 0.5 mg/ml dose was not different from control in the entire fermentation. Yield of the 1.0 mg/ml dose was significantly lower than the control group (p < 0.05) only within the initial 24-h period, and higher dosages (1.5 and 2.0 mg/ml) were lower during the entire fermentation (p < 0.01). Methane yields were well fitted with the Gompertz model, but only the highest level of nitrate inclusion had a significant impact on the majority of model parameters (p < 0.01). The linear regressions between CH4 yields (y) and the amounts of nitrates (x) at progressive fermentation durations (e.g. 6, 12, 24, and 48 h) produced equations with increasing absolute slopes (from -0.069 to -0.517 ml/mg of nitrate). Therefore, nitrate reduced rumen CH4 yield in a dose-dependent manner: the impact of low doses was primarily observed at the initial stages of fermentation, whereas high doses exhibited effectiveness throughout the entire fermentation process. In conclusion, in batch fermentation systems, the dose effect of nitrates on methane yield was time dependent.
This study evaluated the effects of sorghum silages treated with chemical, microbial, and combined additives on fermentative quality, aerobic stability, nutritional composition, and productive performance of confined sheep. Forty uncastrated male sheep were used, distributed among four treatments: silage without additives (control); silage treated with a chemical additive based on organic acids; silage inoculated with Lentilactobacillus buchneri; and silage treated with the combination of both additives. The silages were evaluated after 90 days of storage, and the animals were confined for 60 days, receiving individually adjusted diets. The diets were provided as a total mixed ration composed of sorghum silage, ground corn, cottonseed cake, urea, mineral supplement, and ammonium sulphate, with the concentrate ingredients being mixed with the silage at the time of feeding. No significant differences in dry matter intake were observed among treatments. However, animals fed treated silages, especially with the combination of additives, showed greater intake of non-fibrous carbohydrates and metabolisable energy. The apparent digestibility of dry matter, organic matter, crude protein, and ether extract was higher with the use of additives, particularly in the combined treatment, which also presented the highest total digestible nutrient content. Daily weight gain was greater in sheep fed silages treated with both additives. Furthermore, the additives improved aerobic stability and reduced discard losses during the feeding period. Therefore, the application of chemical and microbial additives to sorghum silage promoted better nutrient preservation, fermentative profile, and aerobic stability, resulting in greater nutrient utilisation and improved productive performance in sheep.
The nutrient composition of the pea grain fraction that escapes precaecal digestion may vary in response to the pea variant, affecting its fermentation characteristics in the hindgut. Quantifying the formation of fermentation end products in vivo remains challenging. Therefore, this study investigated the digestion and fermentation characteristics of 12 pea variants using two combined in vitro assays. In vitro indigestible solids (IVIS) of pea grains, representing the fraction of pea grains escaping precaecal digestion, were incubated for 48 h using a modified Hohenheim gas test with pig faeces as inoculum. Gas production was recorded at nine time points, and NH4+-N and volatile fatty acids (VFA) were measured at 8 and 24 h. Precaecal disappearance was high for starch and crude protein ( >94%), whereas fibre fractions remained largely undigested ( <16%) and were the most abundant and variable fraction in the IVIS. Incubated IVIS differed in potential gas production and maximum rate of gas production among pea variants (p < 0.001, 46.7 to 73.9 mL/200 mg dry matter and 2.9 to 5.1 mL/h, respectively). For metabolite concentrations, an effect of the IVIS was observed for NH4+-N and VFA at 8 and 24 h (p < 0.001). Multivariate regression showed a positive association of acid detergent fibre with the potential gas production (p < 0.001, R2 = 0.82). The concentration of crude protein was positively associated with the NH4+-N concentration at 8 and 24 h (p < 0.001, R2 = 0.85, R2 = 0.86). The crude fibre concentration was negatively associated with the branched-chain fatty acid concentration at 24 h (p = 0.001, R2 = 0.70). Starch concentration was positively associated with gas production at 2 h (p < 0.016, R2 = 0.49) and propionate concentration at 8 h (p < 0.038, R2 = 0.86). To conclude, early-stage propionate production is driven by the precaecal indigestible starch, whereas the fermentation potential is primarily determined by the precaecal indigestible fibre fractions. Formation of metabolites by protein fermentation depends on the concentration of precaecal indigestible protein but may be inhibited with higher fibre concentrations. The differences in fermentation characteristics among IVIS of pea variants were associated with the analysed nutrient composition of the IVIS but not with those of the original grains.
Cassava protein (CP), barley protein (BP) and yellow pea protein (YPP) are important nutrient and integral constituent of staple in pet foods. It is known that the digestion of proteins directly influences their absorption and utilisation. In the present work, we performed in vitro simulated gastrointestinal digestion of three plant proteins as a staple for dog and cat food. The digestion rate of CP, BP and YPP in dog food was 56.33 ± 0.90%, 48.53 ± 0.91%, and 66.96 ± 0.37%, respectively, whereas the digestion rate of CP, BP, and YPP in cat food was 66.25 ± 0.72%, 43.42 ± 0.83%, and 58.05 ± 0.85%, respectively. Using SDS-polyacrylamide gel electrophoresis to determine the molecular weight (MW) of each protein and the products of their digestion, it was revealed that MW of digestion samples decreased, and MW during the small intestine phase was lower than that during the gastric phase. Peptide sequences of digested products were identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and it was found that the total number of peptides in the small intestine digestion samples was higher than that in the gastric phase samples. The MW of peptides obtained from CP was within the range of 1000-1500 Da, while MW of peptides derived from BP and YPP was within the range of 400-2000 Da. In addition, free amino acids were mainly produced in the small intestine phase. Furthermore, the percentage of essential amino acids in the small intestine phase (63 ~ 82%) was higher than that in the gastric phase (37 ~ 63%). Taken together, these findings contribute to the current understanding of the utilisation of plant proteins in dog and cat foods and provide important insights into the selection and application of plant proteins as a staple in dog and cat foods.
This study aimed to evaluate the intake, digestibility, ingestive behaviour, productive performance, rumen fermentation and carcass yield of lambs fed diets with Parkia platycephala pods (PP) replacing ground corn. For this, twenty-eight castrated male lambs (18.34 ± 4.81 kg, 120 days of age), were distributed in randomised blocks with 4 treatments and 7 replicates. Four diets were formulated replacing ground corn with PP (0, 33, 66, and 100%) on a roughage: concentrate ratio of 30:70 on a dry matter basis. The feedlot period lasted for 60 days, and the animals were slaughtered consecutively. The replacing of ground corn with PP reduced the intakes of ether extract and metabolisable energy, digestibility of dry matter, organic matter, crude protein, ether extract, neutral detergent fibre, total digestible nutrients, isovalerate, and omental + mesenteric fat, while it increased the digestibility of non-fibrous carbohydrates, carcass finishing, and the yields of rumen, reticulum, and omasum (p < 0.05). A quadratic effect was observed for the time of chews per rumen bolus, number of rumination chews per day, number of rumination chews per bolus, and number of rumination chews per minute, propionate (p = 0.002), butyrate (p < 0.01) and total short chain fatty acids (SCFA) (p < 0.05) according to the increase in PP levels replacing ground corn in diets offered to lambs. The rumen pH was reduced and the NH3-N increased according to the evaluation period (p < 0.05). The highest concentration of total SCFA was observed in the collection carried out at 09 h (p < 0.05). The use of up to 100% PP in diets offered to lambs is recommended as it provides nutrient intake, weight gain, and carcass yield similar to ground corn.
Phosphorus (P) has several vital functions, and its excretion may have environmental impacts. Thus, an adequate P supply is of utmost importance to meet the requirements of the animals while avoiding unnecessary excretion. Calculation of the P requirement of dairy cows considers factors such as P secretion via milk and P deposition in growing or pregnant animals. Furthermore, a value for the efficiency of P utilisation is applied, which should be determined in animals fed at a marginal P supply to maximise absorption. The objective of the present meta-analysis was thus to estimate the efficiency of P utilisation, accounting for P supply in dairy cows. The dataset included 399 observations published in 77 studies on dairy cows. Data on P intake and faecal P excretion were used to calculate standardised P digestibility, corrected for faecal endogenous P losses. Furthermore, the P requirement and the P supply relative to the requirement were calculated. Linear and non-linear regressions were performed to analyse the relationship between P excretion via faeces and urine and standardised P digestibility with P intake and P supply. Phosphorus intake exceeding the net requirement of dairy cows was excreted with faeces to a large extent, while urinary P excretion had only minor quantitative importance below 5.2 g P/kg DM of feed. The estimated standardised P digestibility at a marginal P supply was 83% and was interpreted as the estimate for efficiency of P utilisation. The data did not indicate that differentiation in P utilisation efficiency between mineral and organic P sources in the feed or by lactation stage is helpful for adequate P supply of dairy cows.
The cis-9 trans-11 and trans-10 cis-12 isomers of conjugated linoleic acid (CLA) are associated with anticancer and lipolytic effects in tissues, respectively, but in lactating cows, the latter isomer reduces the milk fat concentration, a detrimental aspect for the dairy industry, as it reduces the yield of milk derivatives. Therefore, the objective of this study was to evaluate the effect of providing protected palmitic acid (PAP) to grazing lactating Holstein cows supplemented with soybean oil as a source of conjugated linoleic acid, on milk production, fat concentration and mitigation of milk fat depression. Nine multiparous Holstein cows were used, distributed in three groups of three cows each, with initial means of days in milk, live weight, milk production, and number of calvings: 124 ± 16 days, 494 ± 53 kg, 20.9 ± 1.3 kg, and 3.2 ± 2.2, respectively. A crossover design with three treatments was used: control (base diet, BD, = grazing +4 kg concentrate without soybean oil + 2.5 kg corn silage), soybean oil (BD with inclusion of 300 g dry basis soybean oil cow-1 day-1), and soybean oil + PAP (BD with inclusion of 300 g dry basis soybean oil and 412 g PAP cow-1 day-1). The groups of cows were on rotational grazing in a mixed pasture of Alfalfa (Medicago sativa) and Orchard grass (Dactylis glomerata). The variables evaluated were as follows: dry matter intake (DM), milk production, concentration of protein, fat and lactose in milk, and milk fat profile. Statistical analysis was through PROC MIXED and comparison of means with Tukey's test (p < 0.05). There were no differences (p > 0.05) between treatments in dry matter intake, milk production or milk protein and lactose content. But the addition of PAP in the cow diet increased fat-corrected milk production (p = 0.010), yield (p = 0.030) and fat concentration (p = 0.040), and improved the milk fatty acid profile, by increasing (p = 0.010) the concentration of cis-9, trans-11 CLA in milk fat. Soybean oil supplementation in the diet of grazing lactating cows showed no differences in productive variables, and did not cause the expected milk fat depression. However, combining soybean oil with PAP improved the fatty acid profile, increasing the cis-9, trans-11 isomer CLA and palmitic acid in milk fat, with higher yield and fat concentration.
The comprehension of the digestive strategy of red-footed tortoises (Chelonoidis carbonaria) is necessary for effective dietary practices, which prevent metabolic disorders often seen in captivity. The present study evaluated the effects of three extruded diets (high in fibre [Control], high in starch [Starch], and high in fat [Fat]) on the tortoises' preference, nutrient digestibility, faeces quality, fermentation products, and gastrointestinal transit time (GTT). Eighteen adult red-footed tortoises (9 males and 9 females) were used to compare diet palatability. Tortoises were randomly divided into three groups of six, balanced for sex and assigned to one of the experimental diets. The total tract apparent digestibilities (TTAD) of nutrients and energy was measured using chromium oxide (0.25%) as a marker, while GTT was assessed with ferric oxide (2.5%). Faeces were collected for analysis of short and branched-chain fatty acids, lactate, ammonia, and pH. Data were analysed using analysis of variance (ANOVA), and means were compared using Tukey's test (p < 0.05). Diet preference was evaluated with paired t-test, and first-choice preferences by the Chi-square test (p < 0.05). The tortoises showed preference for the Starch and Fat diets, consuming less of the Control diet, high in fibre (p < 0.05). The TTAD of dry matter, organic matter, and gross energy was highest for the Starch diet, intermediate for the Fat diet, and lowest for the Control diet (p < 0.05). The TTAD of fat was lowest for the Fat diet, which resulted in faeces with a high fat content (33.9 ± 2.64% faecal DM; p < 0.05). Tortoises fed the Control diet showed a trend towards a longer GTT, nearly three days longer than those on the other diets (p = 0.075). Short- and branched-chain fatty acids, and faecal lactate, were similar across diets (p > 0.05), though ammonia concentration was lower in the Control diet compared to the Starch diet (p < 0.05). In conclusion, red-footed tortoises showed a preference for diets high in starch and fat over the high fibre formulation. Fat TTAD was limited, decreasing with higher fat intake. Faecal concentrations of fermentation products remained consistent across diets, suggesting extensive absorption of these compounds due to the tortoises' long GTT and the reverse peristalsis.
Two isoenergetic (12.05 MJ/kg ME) and isonitrogenic (approximately 200 g/kg CP) basal diets were prepared using 670 g/kg of wheat with low fibre and/or high fibre contents. Each basal diet was divided into four portions: one remained as is and fed as control (C); the second was the C supplemented with 100 FXU/kg of a commercial xylanase (XYL); the third was the C plus 20 g/kg of inulin (IN) powder; and the fourth was the C supplemented with both XYL and IN at the same inclusion rates, resulting in a total of eight experimental diets. A study was conducted from 10 to 21 days of age involving 320 female Ross 308 broiler chickens. Each diet, in meal form, was fed ad libitum to eight pens, five birds each, following randomisation. Supplementary XYL increased dietary nitrogen corrected apparent metabolisable energy (AMEn) (p < 0.001), dry matter retention (DMR), daily feed intake (FI), weight gain (WG) and reduced feed conversion ratio (FCR) (p < 0.05). Dietary IN tended (p < 0.01) to increase WG and reduce FCR and dietary wheat did not have an impact on growth performance variables (p > 0.05). Birds fed XYL had reduced relative weight of the pancreas (p < 0.050) and there was XYL by IN interaction (p < 0.05) on relative weight of the caeca as it was greater for those fed XYL and IN. No other changes in relative weight of the gastrointestinal tract organs were observed (p > 0.05). Bird fed XYL or IN had greater (p < 0.05) butyric acid (BA) concentration in caecal content. Feeding XYL led to reduced acetic (AA) and propionic acid (PA) concentrations in caecal excreta (p < 0.05) and to a greater BA:AA ratio (p < 0.001). Dietary IN increased blood serum glutathione peroxidase (GSH-Px) (p < 0.05) and XYL increased concentration of hepatic coenzyme Q10 (p < 0.05). The type of dietary wheat did not have an impact on any of the studied variables, suggesting that birds were able to tolerate the fibre contents in this study. It seems that both IN and XYL, can serve as feed enhancers that potentially may promote antioxidant status of birds and help poultry to cope with various stress factors during production. The study further confirms that supplementing wheat-based diets with XYL may be a strategy to mitigate the reduction in available energy and to increase nutrient availability in broiler diets.
In vitro studies of gas production (GP) using rumen fluid obtained from rumen-cannulated animals are common in feed evaluation for ruminants. The objective was to compare sheep faeces with rumen fluid from dairy cows as inocula in the Hohenheim gas test (HGT) using a large number of different-quality feeds. It then was evaluated whether GP obtained by using rumen inoculum (RI-GP) can be estimated from GP using faecal inoculum (FI-GP). Ninety feeds for ruminants including roughages (n = 27), total mixed rations (n = 6), commercial compound feeds for dairy cows (n = 18), cereal grains (n = 10), energy-rich by-products (n = 5), legume grains (n = 6), oilseed meals (n = 6), and other protein-rich feeds (n = 12) were incubated with either rumen inoculum (RI) or faecal inoculum (FI), and GP was recorded at 2, 4, 8, 12, 24, 48, and 72 h. Nonlinear equations were fitted to the GP data to determine GP kinetic parameters. Correlations between RI-GP and FI-GP were calculated for different time points. Linear regressions were calculated to estimate RI-GP from FI-GP using the entire data set or subsets of roughages and concentrates. GP kinetic parameters were lower for all feed categories when incubated with FI instead of RI. On average of all feed samples, the potential GP was 9 mL/200 mg dry matter (DM) lower and the rate of GP was 3.1%/h lower with FI than RI. The estimation of kinetic data for FI included a lag phase of 1.51 h on average, whereas no lag phase was estimated for RI. Estimated parameters indicated an overall lower fermentation activity of FI than RI. However, there was a very similar progression of GP curves of RI-GP and FI-GP. RI-GP after 24 h was significantly correlated with FI-GP in the time period of 24 to 60 h (r = 0.973 - 0.982, including all feed samples). Linear regression analysis showed that RI-GP after 24 h can be estimated from FI-GP after 24 h (Slope = 1.02, R2 = 0.97) and 48 h (Slope = 1.1, R2 = 0.97) including the complete data set. Splitting the data set into roughages and concentrate feeds did not lead to distinctly higher estimation accuracy. In conclusion, sheep faeces can be used as an alternative inoculum for studying a wide range of different-quality feedstuffs. The standard gas test may be modified without the need for rumen-cannulated animals.
Protein supply to ruminants relies mainly on the flow of microbial crude protein (MCP) from the rumen, which is commonly assumed to primarily depend on energy supply. This study evaluated this assumption with recent data and tested if ruminally fermented organic matter (FOM) was a better predictor of MCP flow than total-tract digestible organic matter (DOM) and if more variables could improve the prediction of MCP flow. A previously published data set was extended by additional studies resulting in a data set of 139 studies including 407 treatment means, typical to Central European rations. Either DOM or FOM had to be reported and estimates of MCP were all based on gastrointestinal measurements. Dietary treatments were restricted to a maximum concentrate proportion of 0.6 and a CP concentration from 10% to 20% of dietary dry matter (DM). Treatments with more than 1% of animal by-products were excluded. Mixed models with "study" as random effect were used to test the ratios between MCP and DOM or FOM. Dietary characteristics including DM intake, OM digestibility (OMD), OM fermentability (OMF), and ruminal N balance and dietary concentrations of CP, rumen-degraded CP (RDP), rumen-undegraded CP (RUP), neutral detergent fibre, starch, and ether extract were evaluated as additional variables to improve prediction accuracy. Regression of MCP flow against DOM (n = 324) or FOM (n = 349) revealed estimates of 139 g ± 36 g and 164 g ± 40 g of MCP for each kg of DOM or FOM, respectively. The best-fitting mixed model estimating MCP/DOM [g/kg] was 312-2.75 · OMD - 0.229 · RUP + 0.290 · RDP whereas MCP/FOM [g/kg] may be calculated as 294-2.80 · OMF + 0.401 · RDP, with OMD and OMF in [%] and RDP and RUP in [g/kg DM]. Microbial CP flow [g/d] was most accurately described as 1896 + 110 · DOM - 23.7 · OMD - 0.164 · RUP + 0.153 · RDP, with DOM in [kg], OMD in [%] and RDP and RUP in [g/d]. Predictions based on DOM were at least as precise as FOM-based predictions and comparison with published models revealed that the presented models were of similar accuracy as the ones from literature.
Press cake silage (PCS) is a by-product of biorefining, which can substitute unprocessed grass or grass-clover silage (GCS) in ruminant feeding. The aim of this study was to examine the effect of including re-ensiled PCS from GCS in dairy cows' diet on feed intake, milk production and composition, feed conversion, apparent total tract digestibility (ATTD) as well as feed sorting and rumination behaviour compared to a control ration. Three total mixed rations (TMR) were tested in this experiment differing in PCS and GCS proportion in forage: 0% PCS and 50% GCS (CON), 25% PCS and 25% GCS (PCS25) and 50% PCS and 0% GCS (PCS50). The study was designed as a cross-over trial with six Holstein Friesian and nine Simmental cows (average 624 ± 68 kg body weight and 60 ± 20 days in milk at the start of the trial). The experiment consisted of three experimental runs, each lasting for 35 days with a 14 days adaptation phase and a 21 days measurement period. Diets were fed as TMR containing 37% grass silage, 26% concentrates and differing proportions of PCS or GCS depending on experimental group (37% GCS in CON, 18.5% PCS and 18.5% GCS in PCS25, 37% PCS in PCS50). Dry matter intake of dairy cows was higher in the PCS25 compared to the PCS50 group with both groups being not different from the CON treatment. Energy-corrected milk (ECM) production was lowest in the PCS50 group but did not differ significantly between treatments. Milk composition was also similar in all three treatments, except for milk urea content, which was lower in the PCS50 group. Moreover, ATTD of crude protein and ruminal nitrogen balance as well as phosphorus intake and the phosphorus effort for production of 1 kg ECM decreased with rising PCS inclusion in the diet. In contrast, no differences between treatments were found for dry matter, crude protein and energy effort for ECM production as well as for feed sorting and rumination behaviour. In conclusion, replacing GCS by re-ensiled PCS in TMR-diets did not affect ECM production and feed conversion of dairy cows while increasing the utilisation of crude protein and phosphorus. Therefore, re-ensiled PCS can substitute GCS in dairy cows' TMR-diets. However, the long-term effects of decreased phosphorus intake and ATTD of crude protein in cows fed PCS-rich diets should be examined in future studies.
The objective of this study was to evaluate the effects of chitosan (CH), with or without the inclusion of unsaturated fatty acid (UFA) sources, on intake and digestibility, ruminal fermentation, microbial protein synthesis, nitrogen balance, blood metabolites, milk production and composition, and ruminal dynamics and flow in lactating Jersey cows. Five rumen-fistulated Jersey cows [average days in milk = 105 ± 45 days; milk production = 18.0 ± 0.47 kg/day; body weight = 350 ± 25 kg] were used in a 5 × 5 Latin square design with 21-day periods. Five experimental diets were evaluated: (1) Control (CON), basal diet including 30 g/kg of palm oil; (2) (SOCH-) inclusion of 30 g/kg soybean oil (SO) without CH; (3) (WSCH-) inclusion of 160 g/kg whole raw soybeans (WS) without CH; (4) (SOCH+) inclusion of 30 g/kg SO and 2 g/kg CH; (5) (WSCH+) inclusion of 160 g/kg WS and 2 g/kg CH. There was a CH and UFA interaction effect on acetate (C2) concentration (p = 0.005), propionate (C3) concentration (p = 0.008), the C2:C3 ratio (p < 0.001), and the milk fat content of trans-9 C18:1 fatty acid (FA) (p = 0.004). The inclusion of SO, with or without CH, proved to be more active in improving ruminal fermentation patterns by increasing propionate concentration. Furthermore, incorporating SO into the diets of lactating Jersey cows increased CLA, particularly cis-9, trans-11, in milk fat, offering health benefits. We recommend further research to assess the effects of UFA supplementation in combination with CH.