Apparent Digestibility Of CP Research Articles

Seasonal effects on growth, digestibility, and metabolism of preweaned dairy calves in the Southeastern United States.

The aim of the current study was to evaluate seasonal effects on growth, digestibility, and metabolism of dairy calves in Georgia. Holstein calves (n = 48/season) were enrolled at 7 d of age (DOA) from June to Aug (defined as summer, BW = 40 ± 4 kg) and from Nov to Jan (defined as winter, BW = 42 ± 4 kg). Similar general management and feeding practices were applied to calves in both seasons. Calves were housed in individual polyethylene hutches with sand bedding. Starting at 2 DOA, calves were fed a milk replacer (MR) containing 26% protein and 17% fat (0.65 or 0.76 kg of DM/day and mixed with warm water to reach 12.5% solid) and calf starter (CS) was offered ad libitum. Weaning began at 43 DOA by reducing MR 50% until 49 DOA when MR feeding ceased. Calves remained enrolled until 63 DOA. Calf starter intake was recorded daily. Ambient temperature (AT) and relative humidity (RH) were recorded hourly. Rectal temperature and respiration rate were assessed 3 × /wk and BW measured weekly. Blood was collected to analyze metabolites and insulin at 3, 7, 14, 21, 28, 35, 42, 49, 56, and 63 DOA. The apparent total-tract digestibility of nutrients was measured during both the pre- (14.9 - 17.9 DOA) and postweaning (51.0 - 54.0 DOA) periods. The MIXED procedure of SAS was used to analyze repeated measures data. Season, time and their interactions were included as the fixed effects. The CV of hourly AT or RH within a day was calculated as a proxy of within-day variation. The CV of daily average AT or RH within a week was used as the proxy of day-to-day variation. Linear regression analysis between ADG and environmental parameters was performed using GLM procedure. Summer months had greater AT (27 vs. 13°C) but similar RH (83 vs. 81%) relative to winter months, respectively. Rectal temperature and respiration rate were higher during the summer compared with winter. Season had no effect on CS intake before weaning, but summer calves had greater CS intake at 9 wk of age compared with winter calves. No seasonal effect was observed for BW, but summer calves had greater ADG at 3, 5, and 9 wk of age. A negative relationship (r2 = 0.11) between preweaning ADG and within-day AT variation was observed during winter whereas during the summer day-to-day AT variation was negatively associated with preweaning ADG (r2 = 0.06). Compared with calves raised during winter, calves in summer had lower apparent total-tract digestibility of DM, OM and CP during the preweaning period. Further, summer calves had lower circulating glucose before and after weaning and lower blood BHB concentrations following weaning compared with calves raised in winter. In conclusion, in Georgia, the within-day and day-to-day AT variations affect preweaned calf growth, and calves raised during summer had lower nutrient digestibility and altered metabolism relative to calves raised in winter.

Effects of Substitution of Wheat Straw by Giant Reed on Growth Performance, Serum Biochemical Parameters, Nutrient Digestibility, and Antioxidant Properties of Sheep.

The development and utilization of unconventional forage resources is crucial to alleviating the current situation of shortage of forage resources. Giant reed (Arundo donax) is a promising forage resource from the Poaceae family, one of the largest herbaceous plants globally, with fast growth, high biomass yield, and strong ecological adaptability. However, there are still very few reports on the use of giant reed in livestock and poultry production. The purpose of this study was to evaluate the effects of adding giant reed instead of wheat straw in total mixed ration (TMR) diets on growth performance, blood biochemical indexes, nutrient digestibility, and antioxidant properties of sheep, thereby providing a theoretical basis for the development and utilization of giant reed herbage resources. A total of 24 fattening sheep (Han × Duper) with similar body weight (20 kg), age (2 months), and health status were randomly divided into four groups with six replicates per group. Sheep in the control group were fed a basal diet (CON), and those in the experimental groups were fed giant reed Lvzhou No. 1 instead of wheat straw, with replacement proportions of 10% (GR10), 20% (GR20), and 30% (GR30) of the total diet, respectively. The results showed that (1) the body weight (FBW) and average daily gain (ADG) of sheep in the GR20 and GR30 groups were higher than those of sheep in the CON and GR10 groups (p < 0.05). Meanwhile, the feed to gain ratio (F/G) of sheep in the GR20 and GR30 groups was lower than those sheep in the CON and GR10 groups (p < 0.05), and the F/G of the GR30 group was lower than that of the GR20 group (p < 0.05). (2) The apparent digestibility of DM and CP in groups GR10, GR20 and GR30 was significantly higher than that in group CON (p < 0.005). The digestibility of NDF and ADF in groups GR20, and GR30 was significantly higher than that in the CON and GR10 groups (p < 0.05). (3) dietary substitution of giant reed for wheat straw had no effect on serum biochemical indices, except serum glucose (GLU, p = 0.014) of sheep. In addition, the substitution of giant reed for wheat straw had a tendency to decrease serum urea content of sheep (p = 0.098). (4) Dietary substitution of giant reed for wheat straw significantly improved serum T-SOD (p < 0.001) and T-AOC (p < 0.001), and significantly decreased MDA (p < 0.001) of sheep. In conclusion, replacing wheat straw with giant reed can significantly enhance growth performance, nutrient digestibility, and antioxidant capacity in sheep without adverse effects on their normal physiological functions.

The effect of protease supplementation in broiler chicken diets containing maize from different batches on growth performance and nutrient digestibility

Maize is the primary energy source in poultry diets. Nutritional and physical traits related to maize composition can affect nutrient utilization, as well as the efficacy of exogenous enzymes. A study was conducted to evaluate the effect of maize from different batches and protease supplementation on growth performance and ileal nutrient digestibility of broiler chickens from 1 to 40 days of age. A total of 1 920-day-old Ross 308 male chicks were assigned in a complete randomized design distributed into a 2 × 2 factorial arrangement comprising maize from two different batches (A and B) without and with protease (0 and 200 g/t), totaling 4 treatments and 12 replicates of 40 broiler chickens each. Experimental diets were divided into starter, grower I, grower II, and finisher phases. Both maize types were analyzed for nutritional composition, hardness, and structural differences in the starch granules via scanning electron microscopy. Feed intake, weight gain (WG), and feed conversion ratio (FCR) were evaluated. Ileal digesta was collected at 35 days to determine the apparent ileal digestibility (AID) of DM, CP, and ileal digestible energy (IDE). Hardness was higher in maize grains from batch A (P < 0.05), which may be associated with the denser and compact starch granules observed in electron microscopy. Broiler chickens fed maize from batch B and supplemented with protease showed greater WG and better FCR from 9 to 19 days (P < 0.05). From 1 to 40 days, birds fed the maize B diet had greater WG and lower FCR compared to those fed the maize A diet (P < 0.05). In the total period, protease supplementation reduced FCR (P < 0.01). No differences were found for AID of DM and CP, but broilers fed maize B diets had greater IDE (P < 0.05). In conclusion, although nutrient ileal digestibility was unaffected by treatments, the use of maize B led to superior growth performance and energy utilization due to its softer endosperm and starch composition, and protease supplementation reduced FCR and increased IDE regardless of maize batch.

In vitro and in vivo evaluation of the nutritional value of various hydrolyzed feather meals and comparison of their effect on performance and carcass characteristics of broilers

In the current study, the nutritional value of various hydrolyzed feather meals (HFM) was investigated in two separate experiments (an in vitro and an in vivo experiment). The in vitro experiment was based on a completely randomized design with five replications and seven treatments including (1) Raw feather meal (RFM), (2) HFM by autoclave (Au-HFM), (3) Fermented feather meal (FFM) by Bacillus licheniformis (Bl-FFM), (4) FFM by Bacillus subtilis (Bs-FFM), (5) FFM by Aspergillus niger (An-FFM), (6) FFM by Bacillus licheniformis + Bacillus subtilis + Aspergillus niger (Co-FFM), and (7) HFM by an enzyme (En-HFM). The highest in vitro pepsin-pancreatin and apparent ileal CP digestibility were observed in Co-FFM, and the lowest amount belonged to RFM (P < 0.05). For the in-vivo experiment, 480 1-d-old male Ross 308 broilers were distributed in the experimental units in a completely randomized design with 8 treatments and 5 replicates (12 chicks/replicate). The treatments were: (1) Control diet (without feather meal (FM)), (2), (3), (4), (5), (6), (7), and (8), diets containing 4 % RFM, Au-HFM, Bl-FFM, Bs-FFM, An-FFM, Co-FFM, and En-HFM, respectively. For the in-vivo study, the birds fed control and Co-FFM diets had the highest feed intake, body weight gain, and the lowest feed conversion ratio compared to the other treatments (P < 0.05). The broilers fed the control and FFMs diets had the lowest relative weight of abdominal fat and liver compared to the other groups (P < 0.05). Therefore, our findings advise the poultry feed industry to look for Co-FFM as an effective alternative and cheaper feed ingredient to replace part of soybean meal in poultry diet.

Soybean Oil, Linoleic Acid Source, in Lamb Diets: Intake, Digestibility, Performance, Ingestive Behaviour, and Blood Metabolites.

The objective of the current study was to evaluate the effects of soybean oil inclusion in diets on feeding behaviour, digestibility, performance, and blood metabolites of feedlot lambs. Forty non-castrated Santa Inês lambs with a mean age of 5 months and initial body weight of 34.88 ± 3.19 kg were used in a 40-day feeding trial. The lambs were distributed in five experimental diets with the inclusion of increasing soybean oil (SO) levels: 0, 30, 60, 90, and 120 g/kg DM. The SO inclusion promoted a linear reduction in DM intake (p < 0.001), crude protein (CP, p < 0.001), non-fibrous carbohydrates (NFC, p < 0.001), and total digestible nutrients (TDN, p = 0.004). There was an increasing quadratic effect on the intake of ether extract (EE; p = 0.002) and decreasing for neutral detergent fiber (p = 0.005). The soybean oil inclusion promoted the greater apparent digestibility of CP (p = 0.016), EE (p = 0.005), NDFom (p < 0.001), and TDN (p < 0.001); on the other hand, the apparent digestibility of NFC (p = 0.005) was decreased. The average daily gain decreased (p < 0.001) with SO inclusion. The SO inclusion increased feeding time (p = 0.004), reduced the efficiency of DM rumination (p = 0.001), and reduced the concentration of blood N-ureic (p < 0.001). Considering the productive parameters, SO can be included in diets and it is recommended that we include SO of up to 41 g/kg DM in diets for fattening lambs as the ideal maximum level. The strategy implemented to adapt lambs to increasing levels of high-fat diet mitigated the detrimental effects of lipids on the rumen, with high-density energy intake being the constraining factor on performance.

Effects of potassium diformate on growth performance, apparent digestibility of nutrients, serum biochemical indices, and intestinal microflora in Cherry Valley ducks

This study was performed to investigate the effects of potassium diformate (KDF) on growth performance, apparent digestibility of nutrients, serum biochemical indices, and intestinal microflora of Cherry Valley ducks. In total, 144 female healthy 1-day-old Cherry Valley ducks were divided into 3 groups with 6 replicates per group and 8 ducks per replicate according to the principle of similar body weight. The control group was fed a basic diet. In the 2 experimental groups, 0.8% and 1.2% KDF was added to the basic diet, respectively. The trial period was 6 wk and the pretrial period was 3 wk. The final weight and ADG were significantly higher in the 0.8% KDF group than in the control group (P < 0.05). The feed-to-gain ratio was significantly lower in both KDF groups than in the control group (P < 0.05). The apparent digestibility of CP was significantly higher in both KDF groups than in the control group (P < 0.05). The apparent digestibility of calcium was also significantly higher in the 0.8% KDF group (P < 0.05). The serum levels of alkaline phosphatase, cholesterol, and total protein were significantly lower in the 0.8% KDF group than in the control group (P < 0.05), the IgM content was significantly higher (P < 0.05), the low-density lipoprotein cholesterol, triglyceride, and urea levels were significantly lower (P < 0.01), and the glucose level was significantly higher (P < 0.01). The serum total protein level was significantly higher in the 1.2% KDF group than in the control group (P < 0.05). The relative abundance of Firmicutes and Patescibacteria in the gut of ducks was significantly higher in the 0.8% KDF group than in the control group (P < 0.05), the relative abundance of unclassified Erysipelotrichaceae and Lactobacillus was significantly higher (P < 0.01), and the relative abundance of Fusobacteriota was significantly lower (P < 0.05). However, the relative abundance of Firmicutes in the gut of ducks was significantly higher in the 1.2% KDF group than in the control group (P < 0.05). The relative abundance of unclassified Erysipelotrichaceae and Clostridium sensu stricto 1 was significantly higher (P < 0.01), as was the relative abundance of Fusobacteriota and Proteobacteria (P < 0.05). These findings indicate that the addition of 0.8% KDF to the diet can improve the growth performance of Cherry Valley ducks, promote the absorption of nutrients, change the structure of the microflora in the cecum, and increase the relative abundance of dominant bacteria. It was also shown that there was a significant difference between the 0.8% and 1.2% KDF levels which suggest that the safety margin for overdosing is quite low.

Prolonged feeding of high-concentrate diet remodels the hindgut microbiome and modulates nutrient degradation in the rumen and the total gastrointestinal tract of cows

The aims of this research were to evaluate how prolonged feeding of a high-concentrate diet affects the ruminal degradation kinetics of fiber and starch, and to evaluate the effects of the high-concentrate diet on apparent total-tract nutrient digestibility in dairy cows. We also investigated the dysbiotic effects and the remodeling of the hindgut microbiome with prolonged high-concentrate feeding. Nine Holstein cows were used in 2 experimental periods; in each period, cows were first fed a 100% forage diet for 1 wk, followed by stepwise adaptation during one week to a high-concentrate (HC) diet (65% concentrate), which was then fed for 4 consecutive weeks. The kinetics of in situ ruminal degradability of grass silage (DM and NDF), corn grain and wheat grain (DM and starch), as well as the apparent total-tract nutrient digestibility were evaluated in the forage feeding and in wk 4 on the HC diet. Whereas the hindgut microbiome and fermentation profile were evaluated on a weekly basis. Regarding the in situ ruminal degradability due to grain type, the rate of degradation of the potentially degradable fraction and the effective rumen degradability of wheat grain were greater compared with corn grain. The in situ ruminal degradability of NDF decreased with the HC diet. However, the apparent total-tract digestibility of CP, fat, starch, NDF, ADF, and NFC increased with the HC diet compared with forage feeding. In addition, the HC diet increased the concentration of short-chain fatty acids in the hindgut, lowering fecal pH by 0.6 units, which correlated positively with microbial α diversity. This resulted in lower α diversity with the HC diet; however, α diversity (number of amplicon sequence variants) showed recovery in wk 3 and 4 on HC; in addition, microbial β diversity did not change from wk 2 onward on the HC diet. Two microbial enterotypes were identified: one for the forage diet with abundance of Akkermansia and Anaerosporobacter, and another enterotype for the HC diet with enrichment in Bifidobacterium and Butyrivibrio. Overall, results show that major microbial shifts and hindgut dysbiosis occurred in wk 1 on the HC diet. However, the hindgut microbial diversity of cows adapted after 3 wk of consuming the starch-rich ration. Thus, feeding the HC diet impaired fiber degradation in the rumen, but increased apparent total-tract nutrient digestibility. Likely, the forage diet contained less digestible NDF than the HC diet due to greater inclusion of forages with lower NDF digestibility and lower inclusion of more digestible nonforage NDF. Results also suggest that the adaptation of the hindgut microbial diversity of cows observed 3 weeks after the diet transition likely contributed to enhance total-tract nutrient digestibility.

Lycium barbarum (Wolfberry) Branches and Leaves Enhance the Growth Performance and Improve the Rumen Microbiota in Hu Sheep.

The Lycium barbarum branches and leaves (LBL) are known to contain a range of active substances that have positive effects on animal immunity and antioxidation. This study aimed to examine how LBL impacts the growth and slaughter performance as well as rumen fermentation and microbiota in Hu sheep. A total of 50 male Hu sheep of indigenous origin, aged 3 months, were randomly divided into 5 groups of 10 sheep each. The groups were given different levels of LBL supplementation (0%, 3%, 6%, 9%, and 12%) to evaluate growth performance and nutrient apparent digestibility. Rumen fluid samples were collected for analysis of the fermentation parameters and rumen chyme was examined to study the rumen microbiota. The slaughter performance, meat quality, and organ index were evaluated at the conclusion of the experiment. The results showed that the final body weight and average daily gain of the LBL1 group were significantly higher than those of the CON group, LBL3 group, and LBL4 group (p < 0.05). The average dry matter intake of the LBL4 group was significantly lower than that of other experimental groups (p < 0.05). The apparent digestibility of CP in the LBL1 and LBL2 groups was higher than that in other experimental groups (p < 0.05). At the same time, the eye muscle area and grade-rule (GR) value of Hu sheep in the LBL1 group significantly increased and the quality of Hu sheep meat improved (p < 0.05). There was no significant difference in organ weight and organ index between the experimental groups (p > 0.05). The pH of the rumen fluid in the LBL1 group was significantly lower than that in the CON group (p < 0.05). There was no significant difference in the NH3-N content between the experimental groups (p > 0.05). The propionate and valerate in the rumen fluid of Hu sheep in the LBL2 group were significantly higher than those in other experimental groups (p < 0.05). In addition, this had no significant effect on the structure and abundance of the rumen microbiota (p > 0.05). LBL is a promising functional feed. Adding an appropriate amount of LBL to the diet can improve the feed efficiency, growth performance, and meat quality of Hu sheep but has no adverse effects on the rumen. In this experiment, the appropriate supplemental level of LBL in the diet was 3%.

Activated Charcoal Affects the Bioavailability of Cyanide in Weaned Pigs: Growth Performance, Nutrient Retention and Cyanide Degradability in Various Segments of the Gastro-Intestinal Tract

Sixty-four weaned pigs (Large White-Landrace, age = 8 weeks) were assigned to eight groups with eight pigs per group, and each pig was a replicate. A set of four diets formulated, contained cassava root meal (CRM) at 0%, 25%, 50% and 75% replacing maize such that they were without activated charcoal while the next set of four diets had activated charcoal (AC) at 40g/kg diet as a supplement. Thus, making eight diets. The experiment was a 2 x 4 factorial arrangement in a completely randomised design. The result indicated that the interaction effect differs significantly (p&lt; 0.05) for Live Weight (LW), Daily Weight Gain (DWG), Daily Feed Intake (DFI), Feed-Gain ratio (F:G) and Hydrogen Cyanide (HCN) intake. Diets with activated charcoal supplementation (ACS) differed significantly (p&lt;0.05) for LW such that the control group had a higher value (29.06kg) which is similar to that of groups 2 (28.25kg) and 3(28.63kg). Diets with ACS (0% and 50% CRM) for DWG recorded the highest value (0.35kg/day) (p&lt;0.05). The least F:G was observed in diet with 50% CRM with ACS. Cyanide intake increased with increasing CRM with or without AC supplementation. Apparent digestibility of CP, EE, CF, NFE and HCN were significantly affected (p&lt;0.05) (i.e by both varying levels of CRM and activated charcoal supplementation) except for nitrogen-free-extract at 25% CRM level where charcoal supplementation had no effect. Digestibility of HCN improved significantly (&lt;0.05) across the CRM levels. The interaction effects of CRM and ACS differ (p&lt;0.05) for cyanide degradability in the stomach, caecum and large intestine. It can be concluded that weaned pigs fed 50% CRM with ACS had higher DWG and F:G. Diets without ACS had significantly better nutrient digestibility at 0% level (control) except for CP and ash at 50% CRM. ACS significantly (p&lt;0.05) influenced HCN degradability but more in the stomach and caecum at 25% CRM level. For improved weight and feed conversion, 50% CRM replacement for maize with ACS is recommended.

Influence of dietary Salicornia europaea L. extract supplementation on feed efficiency of Altay sheep by modifying their gastrointestinal bacteria communities.

This experiment aimed to examine the impact of Salicornia europaea L. extract on sheep growth performance, rumen fermentation variables, nutrient apparent digestibility, and gastrointestinal microbial diversity. Forty-eight male Altay sheep, weighing 32.5 ± 2.8 kg and approximately 3.5 months old, were chosen. Four dietary treatments, each consisting of four replicates and three sheep per replicate, were distributed randomly to the sheep. The pelleted total mixed ration containing Salicornia europaea L. extract at 0.0, 0.2, 0.4, and 0.6% DM was freely available to the sheep in the four treatment groups. The 56-day experiment consisted of 45 days of measurements followed by 11 days of adaptation. The growth performance was not affected by nutrition Salicornia europaea L. extract (p ≤ 0.05), but the feed-to-gain ratio was reduced when the extract was given at 0.4% DM (p ≤ 0.05). Compared to the 0 and 0.2% treatments, the apparent digestibility of DM, OM, NDF, and ADF was substantially greater in the 0.4, and 0.6% treatments. Furthermore, compared to sheep in the 0 and 0.2% groups, sheep in the 0.6% group had a noticeably higher apparent digestibility of CP. As the amount of Salicornia europaea L. extract added to the rumen fluid rose, the molar ratio of acetic acid increased. In contrast, the molar ratio of propionic acid gradually decreased, and the total volatile fatty acid content gradually reduced. Thus, adding a suitable quantity of Salicornia europaea L. extract to the sheep ration is natural and secure, which may improve the environmental sustainability of small ruminant production systems.

47 Inclusion of black soldier fly (Hermetia illucens) larvae frass as an alternative protein source in the diet of Florida native yearling ewes.

Abstract The objective of the study was to evaluate the effects of partially replacing soybean meal (SBM) with black soldier fly larvae frass (BSFL) on nutrient digestibility, growth performance, and blood profile of ewes consuming diets with approximately 10% SBM on a DM basis. Six yearling Florida native ewes, averaging (mean ± SD) 44 ± 3 kg BW were enrolled in a replicated 3 × 3 Latin square design with 3 experimental periods of 21 d each (14 d adaptation + 4 d samples collection + 3 d washout). First 14 d of each period, ewes were housed in 7.4 × 1.8 m individual pens with rubber mats, one automatic waterer and two plastic feeders. During collection, ewes were moved to 1.4 × 0.7 m metabolic crates equipped with an individual waterer and feeder and two trays for the collection of feces and urine. Animals were fed TMR ad libitum twice daily at 0730 and 1530 h consisting of different levels of SBM replacement with BSFL, as follows: no replacement (CON), partial replacement of SBM with 25% BSFL (BSFL25) and 50% BSFL (BSFL50) on a DM basis. Data on DM and nutrient intake, excretion, and apparent digestibility, and also plasma concentrations of glucose and blood urea nitrogen (BUN), and urine concentrations of allantoin, urine blood nitrogen, and uric acid, were collected. Data were analyzed with SAS 9.4 evaluating orthogonal polynomial contrasts to determine linear and quadratic effects of SBM replacement with BSFL for each response variable. The intakes of DM, NDF, ADF, EE, and starch were greater for BSFL25 compared with control (Quadratic effect; P &amp;lt; 0.01) while no differences were observed between BSFL25 and BSFL50. Similarly apparent digestibilities of DM, NDF, ADF and starch was less for BSFL25 than CON (Quadratic effect; P ≤ 0.01). Intake of CP linearly increased (P &amp;lt; 0.01) with BSFL, while apparent digestibility of CP linearly decreased and that of EE increased, with inclusion of BSFL. There was a quadratic effect of BSFL on total feces excretion (P &amp;lt; 0.01) and water consumption (P &amp;lt; 0.01) being greater in BSFL25 compared with CON. Urine BUN (P &amp;lt; 0.01) and urine nitrogen (P &amp;lt; 0.01) linearly increased with BSFL inclusion. Results indicate that partial replacement of SBM with BSFL in the diet of yearling Florida native ewes may quadratically increase feed intake and decrease nutrient apparent digestibility. Further research is needed to explore the long-term implications of incorporating BSFL into animal diets, considering their impact on overall growth and performance.

Effect of an Escherichia coli-derived phytase and a carbohydrase-protease cocktail derived from Bacillus spp. on performance, digestibility, bone mineralization and gut morphology in broilers fed different nutrient density diets.

Enzyme combinations, particularly phytase (PHY) with various carbohydrases and proteases, are utilized in commercial broiler production to enhance nutrient and energy bioavailability. A feeding study was undertaken to determine whether the efficiency of an Escherichia coli-derived PHY and a feed enzyme complex (FEC) derived from Bacillus spp. containing carbohydrase and protease as main activities in broiler chickens is dependent on diet quality. A total of 900 male one-day-old broiler chickens (Ross 308) were assigned to a 2×3 factorial arrangement of the treatments with 2 different nutrient density diets, standard nutrient diet (SN diet) and a low-nutrient diet (LN diet; -100kcal/kg for AMEn and -5% for crude protein [CP] and limiting amino acids), and 3 enzyme treatments (control [no enzymes], PHY and PHY+FEC). Each treatment group was composed of 6 replicates of 25 birds each. The LN diet caused a decrease in performance index, tibia length and diameter, tibia calcium content and jejunal villus surface area (VSA). The interaction effects between diet and enzyme supplementation were observed (p<0.05) on overall average daily gain (ADG), performance index, tibia ash content and jejunal villus height (VH) and VSA, with the favourable benefits of PHY+FEC treatment being more pronounced in the LN diets. Regardless of dietary nutrient density, supplementation with PHY alone or combined with FEC enhanced (p<0.05) final body weight, overall ADG and jejunal villus height (VH)/crypt depth, with the highest values observed in the PHY+FEC group. The PHY+FEC treatment also improved (p<0.05) overall feed conversion ratio, apparent ileal digestibility of dry matter, organic matter, CP, and energy, and tibia phosphorus content compared to the control treatment. The results indicate that the simultaneous addition of PHY and FEC to the LN diets improved the growth rate, bone mineralization and gut morphology.

Replacing the forage portion of the ration with triticale hay improves the performance of Holstein dairy cows

The aim of the present study was to assess the effect of replacing the forage portion (alfalfa, corn silage, and barley straw) in the diet of lactating Holstein cows with triticale hay (TH, × Triticosecale L.) on DMI, digestibility, ruminal fermentation variables, estimated microbial-N synthesis (EMNS), and milk production and composition. Eight Holstein cows were used in a replicated Latin square design (two 4 × 4 squares) with four 28-d periods and 4 treatments, including a TH-free diet (control), and diets replacing 33%, 66%, and 100% of the forage portion with TH. Cows were fed ad libitum with 10% carryover during the experimental periods. Intakes and in vivo digestibilities of dry matter, organic matter, crude protein, and ash-free neutral detergent fiber, rumen pH, ammonia-N, total and individual short-chain fatty acids, protozoa, and bacteria populations were evaluated using specific methods. Moreover, in vitro total gas and methane release and in vivo urinary purine derivatives, EMNS, milk production, and composition were measured. The results showed that TH diets lowered DMI, compared with the control. Apparent digestibilities of DM, OM, CP, and NDF increased with dietary TH inclusion. The addition of TH instead of the diet forage portion increased in vivo rumen pH; acetic, propionic, valeric, and isovaleric acids concentrations; cellulolytic bacteria number; and in vitro gas production. In vivo rumen ammonia-N, short-chain fatty acids, butyric acid, in vivo and in vitro total protozoa and Entodiniinae numbers, and in vitro methane production decreased with increasing dietary levels of TH instead of the forage portion. The dietary addition of TH did not affect milk yield, protein, and lactose, but increased fat-corrected milk, milk fat, fat-corrected milk:DMI ratio, and milk yield:DMI ratio. Milk urea N decreased, but urinary purine derivatives excretion and EMNS increased with increasing levels of TH in the diet. For variables with significant changes, except for isovaleric acid, there was a linear response of animals to increasing levels of TH in the diet. Results suggest that TH, which is grown with less water compared with alfalfa, corn forage, and straw, is a potential alternative to those forages by increasing milk production efficiency, milk fat, and decreasing methane emission.

Dietary crude protein time-dependently modulates the bacterial community and metabolites and changes dietary nutrient efficiency in growing pigs

The reduced nutrient digestibility of low-protein (LP) diets has been shown to be caused by the weakened fermentative capacity of the post-gut flora. The dynamic regulation of dietary protein contents on post-gut microbial population and fermentative metabolism is unclear. Twelve growing barrows (19.9 ± 0.8 kg) fitted with a T-cannula at the blind end of the cecum were randomly administered a high-protein (HP, 21.5% crude protein [CP]) diet or an LP (15.5% CP) diet for 28 d. The cecal content and feces were collected at d 1, 14, and 28 of the experiment for microflora structures and metabolite concentrations analysis. The nutrient digestibility coefficient and plasma biochemical parameters were also determined. Compared with the HP treatment, the LP treatment showed decreased plasma urea nitrogen concentration and apparent total tract digestibility of dry matter, gross energy, and CP (P < 0.01). In addition, urinary nitrogen losses, total nitrogen losses, and daily nitrogen retention in the LP treatment were lower than those in the HP treatment (P < 0.01), and the nitrogen retention-to-nitrogen intake ratio in the LP treatment was increased (P < 0.01). The HP group showed increased cecal total short-chain fatty acids (SCFA) concentration and fecal propionate, butyrate, and total SCFA concentrations (P < 0.05) on d 14 and 28, which may be mainly related to the elevated abundance of SCFA-producing bacteria, such as Ruminococcus, Lactobacillus, and Prevotella (P < 0.05). Probiotics, such as Bifidobacterium, Bacteroidales S24-7, and Rikenella, enriched in the LP treatment possibly contributed to reduced plasma endotoxin content. The differences in the abundances of almost all the above-mentioned flora appeared on d 28 but not d 14. Likewise, differences in the Simpson and Shannon indices and clustering patterns of the microbiota between treatments were also only observed on d 28. To sum up, in a time-dependent manner, the LP diet increased probiotics with gut-improving functions and decreased SCFA-producing bacteria, which may cause enhanced intestine health and reduced nutrient digestibility.

Effect of physical form of starter feed on nutrient digestibility of dairy calves

Abstract. The present experiment aimed to compare the effect of the physical form of a starter for dairy replacement calves on some rumen fermentation parameters. Nine male calves 4 days old and averaging 41.3 kg (SD = 3.6) were divided into three groups. The calves were housed in individual hutches bedded with straw. The calves were weaned at the age of 56 days of age and remained in the experiment until they reached 70 days. Three different physical forms of starter feeds were tested: 1) Ground starter – starter in meal form with coarsely ground maize (GS); 2) Pelleted starter (PS); and 3) Textured starter – a mixture of whole maize grain plus pelleted protein concentrate (TS). The ingredients and chemical composition of the three starter feeds were similar. The calves from all groups received 4 L of whole milk until 56 days of age. The liquid feed was provided twice daily from 4 to 35 days of age, and once daily from 36 to 56 days. From 35 days of age, calves were offered a free choice of alfalfa hay. OM digestibility was lower in calves that received ground starter compared to calves fed pelleted starter and textured starter. Apparent total tract digestibility of CP was the lowest in calves fed GS compared to those receiving PS and TS (P &lt;0.05). No statistically significant difference in CP digestibility was observed between PS and TS-fed calves. EE digestibility was significantly lower in calves that received GS compared to those that received PS (P &lt;0.05), but not different from EE digestibility in calves fed TS. The highest EE digestibility was that in PS-fed calves. CF digestibility was the highest in calves that received PS and the lowest in those fed GS, with significant differences (P &lt;0.05). There was no significant difference in NFE digestibility among tested physical forms of starter feeds.

Approaches to determine the efficiency of novel 3-phytase from Klebsiella pneumoniae and commercial phytase in broilers from 1 to 14 d of age

This study aimed to evaluate the effects of a laboratory 3-phytase (the expression of the phyK gene, Lab-Phy) and a commercial 6-phytase (Quantum Blue 40 P, Com-Phy) alone and in combination (corn-soy-based diets) in broilers. A total of 400, day-old Ross 308 male broilers were randomly assigned to 5 treatments with 10 replicate cages (8 chicks/cage) for a 14-day trial. Experimental treatments included the positive control (0.95% Ca and 0.48% nonphytate phosphorus (nPP), PC), negative control (0.90% Ca and 0.22% nPP, NC), and NC which was supplemented with Lab-Phy 250 FTY/kg and Com-Phy 250 FTY/kg alone or in combination of Lab-Phy 125 FTY/kg and Com-Phy 125 FTY/kg. The inclusion of Lab-Phy in the NC diet significantly improved the P and Ca content in the tibia compared to the NC group. Moreover, the inclusion of Com-Phy alone and in combination with Lab-Phy in the NC diet significantly increased the P and Ca content in the tibia compared to the Lab-Phy. The mRNA expression of NaPi-IIb was upregulated in the duodenum by the reduction of nPP and downregulated by the inclusion of any phytase, whereas other nutrient transporters were not influenced by the reduction of nPP or the addition of phytase in the small intestine mucosa. Broilers receiving the NC diet obtained the lowest body weight (BW) and body weight gain (BWG) at 8 to 14 and 1 to 14 d of age. The NC group showed the lowest villi height and surface area, Newcastle disease (ND) antibody titer, and digestibility of nutrients compared to the PC group at 14 d of age. Supplementing the NC diet with the Lab-Phy and Com-Phy individually, or in combination tended to improve BW, BWG, tibia characteristics, villi characteristics, ND, and retained CP and P, and apparent ileal digestibility of CP, P, methionine, and threonine. The present research indicated that the studied traits by the combination of phytases were slightly better than the average of the 2 individually, suggesting there might be some value in combining the laboratory and commercial phytases.

Comparative Evaluation of Extruded Complete Feeds based on Finger Millet (Eleusine coracana) Straw, Areca (Areca catechu) Sheath and Maize (Zea mays) Cob in Mandya Lambs

Background: Although crop residues rich in lignocellulose are a potential source of energy, their utilization is limited due to lack of lignolytic activity of the rumen microbial population. Feed processing by heat treatment is known to break the ligno-cellulolse complexes, in which extrusion has been reported as one of the best processing techniques to improve the nutritional value and efficient utilization of complete diets. A comparative evaluation of extruded complete feed based on finger millet straw, a conventional crop residue, along with areca sheath and maize cob has been taken up in this study. Methods: The extruded complete feed was prepared using roughage and concentrate at proportion of 40:60, respectively. Twenty four Mandya lambs of about 3 to 4 months of age with body weight ranging from 7.8 to 12.9 kg were divided into three groups of eight each in a completely randomized design. Feeding trial was carried out for 12 weeks. The animals were randomly assigned to one of the treatment groups viz., T1 (Finger millet straw based extruded complete feed), T2 (Areca sheath based extruded complete feed) and T3 (Maize cob based extruded complete feed). Digestion trial was conducted using 5 animals in each group during the last week of the growth trial. Result: Analysis of chemical composition (%) revealed that, maize cob and areca sheath were comparable with finger millet straw except that the maize cob contained lower total ash (2.52 v/s 8.61) and higher NDF and hemicellulose content (86.66 v/s71.61; 29.79 v/s17.18). Rumen in vitro net gas (ml / 200 mg DM / 24 h) production and energy density (ME MJ / kg DM) was higher in areca sheath and maize cob as compared to finger millet straw. There was significant difference in total DMI (g/d and g/kgW0.75) among the treatment groups (P£0.05). There was also a significant difference in OM, CP, EE and ADF intake (P£0.05). The ADG (g) and FCR (g DMI/ g BW gain) for T1, T2 and T3 groups were statistically non-significant. The mean apparent digestibility (%) of DM, OM, CP, NDF and ADF was significantly different among the treatment groups(P£0.01). The per cent Digestible organic matter in dry matter (DOMDM) (T1:70.89,T2:76.13and T3:63.33) was also significantly different among the treatments (P£0.01). It was concluded that the growth rate of lambs fed finger millet straw, areca sheath and maize cob based extruded complete feeds was comparable and could be utilized to sustain production performance of growing Mandya lambs.

Effect of waste mango silage on the in vitro gas production, in situ digestibility, intake, apparent digestibility, and ruminal characteristics in calf diets.

Mexico is the fifth largest producer of mangoes in the world. For the conservation of agro-industrial waste and crop residues, the ensiling technique has shown good results. This study aimed to evaluate the effect of increasing the level of mango silage (86% waste mango and 14% pangola grass hay) in calf diets on in vitro gas production, in situ digestibility, intake, apparent digestibility, and ruminal characteristics. The diets contained 0 (T0), 30 (T1), 45 (T2), and 60% (T3) mango silage. The partial (24, 48, and 72 h) and cumulative (72 h) biogas, CH4 production, and degradation were determined in the in vitro evaluation. In situ digestibility and estimators of fermentation kinetics of dry matter (DM) and organic matter (OM) were determined. Intake, apparent nutrient digestibility, and rumen parameters of calves (200 kg) were evaluated in a 4 × 4 Latin square design. Response to increased mango silage was calculated by linear and quadratic orthogonal contrasts. In vitro partial and cumulative biogas production decreased linearly (p < 0.05), and the partial and cumulative CH4 production did not show linear or quadratic contrast (p > 0.05); in vitro DM degradation, in vitro neutral detergent fiber degradation, and in vitro acid detergent fiber degradation showed a linear increase (p < 0.05). In situ dry matter digestibility (DMDis), in situ organic matter digestibility (OMDis), b, a + b, c, and effective digestibility (ED) of DMDis, a, a + b, c, and ED of OMDis increased linearly (p < 0.05). Dry matter intake, OM intake, and crude protein intake showed a linear increase (p < 0.05); NDF intake and ADF intake presented a quadratic behavior (p < 0.05). Apparent digestibility of DM, OM, CP, and hemicellulose, pH, N-NH3, total bacterial count, acetate, propionate, butyrate, volatile fatty acids, acetate: propionate ratio, cellulolytic bacteria, and protozoa did not present a linear or quadratic orthogonal effect (p > 0.05). The in vitro, in situ, and in vivo variables demonstrated that up to 60% mango silage can be used for the intensive fattening of calves in confinement.

Effects of substitution of millet straw for corn silage and alfalfa hay on lactation performance, ruminal fermentation, and blood metabolites in late-lactation Holstein dairy cows

The study was conducted to evaluate the effect of replacing dietary corn silage (CS) and alfalfa hay (AH) with millet straw (MS) on the production performance and the ruminal fermentation patterns of Holstein cows in late lactation. For this purpose, forty-eight multiparous Holstein dairy cows blocked by milk yield (32 ± 3.2 kg/d) and days in milk (179 ± 19 d) were randomly allocated to one of four treatments. The diets were formulated with a forage-to-concentrate ratio of 48:52 [dry matter (DM) basis] and contained the same concentrate mixtures, with different forage sources (on a DM basis): (1) Control (60% CS, 40% AH, and 0% MS; on 100% roughage); (2) LMS (54% CS, 36% AH, and 10% MS), (3) MMS (48% CS, 32% AH, and 20% MS), and (4) HMS (42% CS, 28% AH, and 30% MS). The dry matter intake and milk yield were lower in the HMS diet than those in the Control, LMS, and MMS diets (P < 0.01), whereas there was no difference in the Control, LMS, and MMS diets. Compared with the Control diet, 4% FCM, milk protein yield, and N conversion ratio decreased in the MMS and HMS diets (P < 0.01), whereas no difference between the Control and LMS diets was found. Besides, cows fed the HMS diet had lower milk fat yield, lactose percentage, and feed efficiency than those in the Control and LMS diets (P < 0.05), with no difference between the Control, LMS, and MMS diets. The percentage of milk fat and protein was not affected by the diets. Compared with the Control diet, the total VFA concentration was decreased, whereas the ammonia-N concentration was increased in the HMS diet (P < 0.05), with no difference between the Control, LMS, and MMS diets. The molar proportion of acetate and the ratio of acetate to propionate were lower (P < 0.01), while the molar proportion of propionate was higher in the Control diet than that in the MMS and HMS diets (P < 0.01), with no difference between the LMS and MMS diets. Compared with the Control, the apparent digestibility of DM, CP, NDF, and ADF was decreased, while the blood urea nitrogen concentration was increased in the HMS diet (P < 0.05), with no differences in the Control, LMS, and MMS diets. Thus, it was concluded that it is feasible to use MS as a fiber source for late-lactation dairy cows. However, considering the milk production performance and the feed digestibility, the replacement of CS and AH with MS should not exceed 20% of the roughage.

Effects of ensiling sugarcane tops with bacteria-enzyme inoculants on growth performance, nutrient digestibility, and the associated rumen microbiome in beef cattle.

Major challenges when ensiling sugarcane tops include fermentation that results in high quantities of alcohol and decrease in nutrient digestibility due to the accumulation of fiber components. Increased efforts to apply bacteria-enzyme inoculants in silage have the potential to improve nutrient digestibility. This study aimed to evaluate the effects of ensiling sugarcane tops with bacteria-enzyme inoculants or mixed bacterial inoculants on growth performance, nutrient digestibility, and rumen microbiome in beef cattle. Chopped sugarcane tops were ensiled in plastic bags for 60 d after application of 1) no inoculant (control check, CK); 2) bacteria-enzyme inoculants containing Pediococcus acidilactici, Saccharomyces cerevisiae, cellulase, and xylanase (T1, viable colony-forming units of each bacterial strain ≥108 CFU/g; enzyme activity of each enzyme ≥200 U/g); or 3) mixed bacterial inoculants containing Lactobacillus plantarum, Bacillus subtilis, and Aspergillus oryzae (T2, viable colony-forming units of each bacterial strain ≥107 CFU/g). Silages were fed to eighteen Holstein bull calves (n = 6/treatment) weighing 163.83 ± 7.13 kg to determine intake in a 49-d experimental period. The results showed that beef cattle-fed T1 silage or T2 silage had a significantly higher (P < 0.05) average daily gain than those fed CK silage, but the difference in dry matter intake was not significant (P > 0.05). The apparent digestibility of crude protein (CP) and acid detergent fiber (ADF) were higher (P < 0.05) for beef cattle-fed T1 silage or T2 silage than for those fed CK silage. The rumen bacterial community of beef cattle-fed T1 silage or T2 silage had a tendency to increase (P > 0.05) abundance of Firmicutes and Rikenellaceae_RC9_gut_group than those fed CK silage. Rumen fungal communities of beef cattle-fed T1 or T2 silage had a tendency to increase (P > 0.05) abundance of Mortierellomycota and of Mortierella than those fed CK silage. Spearman's rank correlation coefficient showed that the apparent digestibility of ADF for beef cattle was positively correlated with unclassified_p_Ascomycota of the fungal genera (P < 0.05). Neocalimastigomycota of the fungal phyla was strongly positively correlated with the apparent digestibility of neutral detergent fiber (NDF) (P < 0.05). Ruminococcus was positively correlated with the apparent digestibility of CP (P < 0.05). It was concluded that both T1 and T2 improved the growth performance of beef cattle by improving the ruminal apparent digestibility of CP and ADF, and had no significant impact on major rumen microbial communities in beef cattle.