Effect of sugarcane bagasse as industrial by-products treated with Lactobacillus casei TH14, cellulase and molasses on feed utilization, ruminal ecology and milk production of mid-lactating Holstein Friesian cows

The Effect of a Direct Fed Microbial on Liveweight and Milk Production in Dairy Cattle

This longitudinal study aimed to quantify the effects of dietary supplementation of a direct-fed microbial (DFM) consisting of three lactobacilli isolates on milk yield, milk fat and protein yields, somatic cell count (SCC), and liveweight in a single dairy herd in Australia. A total of 150 dairy cows were randomly selected based on parity and days in milk and divided into two groups: control (n = 75) and DFM treatment (n = 75). Throughout the study, the two groups of cows were housed separately in a dry lot yard, and each group had their own feeding area. For the DFM treatment group, selected cows in mid-lactation were supplemented with 10 mL/cow/day of the DFM via top dressing of the feed for the remainder of the lactation and through the dry period, extending into subsequent lactation. The control group had no supplementation. The milk yield and liveweight were recorded daily. Milk samples were collected every two months for milk component analysis (fat, protein, and somatic cell count [SCC]). The DFM-treated cows gained more liveweight across the study (19.40 kg, 95% CI 0.44 kg; 38.30 kg, p = 0.05) compared to the control cows. In the second production year, the DFM-treated cows mobilized more liveweight (-6.06 kg, 95% CI -10.49 kg; -1.61 kg, p = 0.01) and produced more milk (0.39 L/d 95% CI 0.10; 0.89, p = 0.05). Over a full lactation, DFM cows yielded at least 258 L (95% CI 252 L; 265 L) more milk than controls. No significant differences were found in fat and protein yield or SCC. This study suggests that consistent and ongoing supplementation with a Lacticaseibacillus- and Lentilactobacillus-based DFM could have a positive effect on milk production, but further research is needed to understand the underlying mechanism.

Influence of sugarcane bagasse on in vitro degradability, rumen characteristics, nutrients digestibility, blood parameters and milk production of lactating buffaloes

This study aimed to evaluate the use of sugarcane bagasse (SCB) as exclusive roughage in lactating buffaloes on digestibility, milk production and composition, and microbial protein. In vitro dry matter digestion (IVDMD) and organic matter digestion (IVOMD) for SCB as a replacement for barley straw (BS) of the control ration have been determined. In vivo experiment, 55 lactating buffaloes were randomly assigned into five groups. First group was fed the control ration (60% concentrate feed mixture (CFM) and 40% BS), second group was fed 60% CFM and 30% BS + 10% SCB, third group was fed 60% CFM and 20% BS + 20% SCB, fourth group was fed 60% CFM and 10% BS + 30% SCB and fifth group was fed 60% CFM and 40% SCB. Results indicated that IVDMD% and IVOMD% degradability were increased with the inclusion SCB in rations compared with the control. Full replacement of BS by SCB 40% significantly (p < 0.05) increased nutrients digestibility coefficient with improving ruminal basic parameters. Buffaloes fed SCB40 had higher milk component yields, 4% fat corrected milk and plasma proteins, and lower plasma creatinine and cholesterol than control buffaloes (p < 0.05). Finally, the inclusion of SCB up to 40% in lactating buffaloes rations favorably affected rumen fermentation characteristics (in vitro) and improved nutrients digestibility and milk production (in vivo).

Donkey Colostrum and Milk: How Dietary Probiotics Can Affect Metabolomic Profile, Alkaline Sphingomyelinase and Alkaline Phosphatase Activity

Positive results on animal health, feed efficiency, and milk's nutritional content have been obtained after oral administration of probiotics. The aim of the present study was therefore to evaluate the effect of dietary supplementation with high numbers of multispecies probiotic formulations on the milk metabolomic profiles of alkaline sphingomyelinase (alk-SMase) and alkaline phosphatase (ALP) in donkeys. Twenty animals were randomly allocated to receive either a normal diet (group B) or a supplemented diet (group A). Colostrum and milk samples were obtained within 48 h, at 15 days (supplementation start), and at 45 days after parturition. Different metabolomic profiles were observed between colostrum and milk, as were the concentrations of 12 metabolites that changed following 30 days of probiotic supplementation. Alk-SMase activity was found to be higher in donkey colostrum (vs. milk at 15 days); this enzyme, together with ALP, increased in milk after 30 days of probiotic supplementation. The results of the present study provide new insight into the complex changes in donkey colostrum and milk composition in the first 45 days of lactation and how the milk metabolome can be modulated by probiotic supplementation.

Microbial Fermented Liquid Supplementation Improves Nutrient Digestibility, Feed Intake, and Milk Production in Lactating Dairy Cows Fed Total Mixed Ration

The purpose of this experiment was to examine the effects of MFL supplementation on feed intake, nutrient digestibility, milk yield, and milk composition in early lactating dairy cows. Twelve, Thai crossbred Holstein Friesian cows in early lactation, 500 ± 30 kg of body weight (BW), were randomly assigned according to a completely randomized design (CRD). MFL supplementation levels of 0, 100, 200, and 300 mL/d were used as treatments. Experimental animals were fed a total mixed ration (TMR) with a roughage to concentrate ratio (R:C ratio) of 40:60, which contains 12% crude protein (CP) and 70% total digestible nutrient (TDN). Rice straw was a roughage source. MFL supplementation levels had no effect (p > 0.05) on body weight change and dry matter intake (DMI) expressed as %BW, whereas DMI expressed as metabolic body weight (BW^0.75) was linearly (p < 0.05) increased, with the highest at 200 mL/d in the YFL supplementation group (147.5 g/kg BW^0.75), whereas feed intake of organic matter (OM), CP, ether extract (EE), neutral detergent fiber (NDF) and acid detergent fiber (ADF) did not significant (p > 0.05) difference among treatments. Related to apparent digestibility, MFL levels did not affect (p > 0.05) on DM, OM, and EE digestibility, while apparent digestibility of CP, NDF, and ADF were linearly increased (p < 0.05) when increasing MFL supplementation levels, and the highest (p < 0.05) were the 200 and 300 mL/d FML supplemented groups. BUN at 0 h post feeding did not show a significant difference (p > 0.05) between treatments, while at 4 h after feeding, BUN was linearly (p < 0.05) increased from 0, 100, 200, and 300 (mL/day) MFL supplementation, the values were 12.9, 13.1, 19.7, and 18.4 mg/dL, respectively and the highest was 200 mL/head/day for the MFL supplemented group. MFL supplementation did not affect (p > 0.05) milk fat, lactose, solid not fat (SNF), and specific gravity of milk, while MFL supplementation at 200 mL/day caused a linear increase (p < 0.01) in BUN, MUN, milk yield, milk protein, total solids (TS) and 3.5% FCM when supplement levels were increased. In conclusion, MFL supplementation in early lactating dairy cows could improve feed intake, nutrient digestibility, milk yield, and milk composition.

The effect of excessive elemental sulfur addition on feed intake, digestibility, rumen characteristics, blood metabolites and nitrogen balance in Thai native beef cattle fed a diet containing high fresh cassava root

This study aimed to study the effect of excessive elemental sulfur addition on intake, digestibility, rumen characteristics, blood metabolites and nitrogen balance in Thai native beef cattle fed diets containing high fresh cassava root (FCR) supplementation. Four Thai native beef cattle with an initial body weight (BW) of 100 ± 10.0 kg were used and randomly assigned to a 2 × 2 factorial in a 4 × 4 Latin square design. Two levels of FCR supplementation at 15 (FCR-1.5) and 20 g/kg of BW (FCR-2) and two levels of sulfur supplementation in concentrate at 10 (Sulfur-1) and 20 g/kg dry matter concentrate (Sulfur-2) were evaluated. This study showed that sulfur and FCR in combination (p < 0.05) increased dry matter and organic matter digestibility and bacterial population. Sulfur-2 resulted in higher (p < 0.05) sulfur intake and serum thiocyanate concentration than Sulfur-1. FCR-2 had a greater (p < 0.05) FCR intake, total volatile fatty acids and propionate concentration than FCR-1.5. In conclusion, excessive elemental sulfur addition with high FCR supplementation showed no negative effect in Thai native beef cattle.

The Chemical Composition, Fermentation End-Product of Silage, and Aerobic Stability of Cassava Pulp Fermented with Lactobacillus casei TH14 and Additives

This study evaluated the effects of cassava pulp fermented with Lactobacillus casei TH14, urea, and molasses on its chemical composition, the fermentation end-product of silage, and aerobic stability. A 2 × 2 × 2 factorial arrangement with a randomized complete block design was employed. The first factor: level of L. casei TH14 [L; 0 and 105 cfu/kg fresh matter (FM)], the second factor: level of molasses (M; 0 and 4% DM), the third factor: level of urea (U; 0 and 4% DM), and the number of days of fermentation (7, 14, and 21 days) were evaluated using a statistical block. There were interactions among CSP fermented with different additives on DM content (p < 0.05). The control group (CON) and CSP fermented with L, L×M, and L×U had lower DM contents than U, U×M, and L×U×M. The crude protein of CSP was increased by interaction of L×U and U×M additives (p < 0.05 and p < 0.01, respectively). Interaction effects between L and U and NDF content were detected (p < 0.05). The L×U combination resulted in a significantly lower NDF than the other groups. The interaction between L×U×M had no effect on the change in the CSP fermentation process (p > 0.05). The combination of U×M caused a poorer pH than other groups (p < 0.01). The ammonia-N content was higher than others, when CSP was fermented with L×U (p < 0.01) or U×M (p < 0.05), respectively. The lactic acid levels in fermented CSP were higher (p < 0.01) than in other groups through the L. casei. The interaction between L×U×M had an influence on lactic acid bacteria (LAB) (p < 0.01) and aerobic bacteria (p < 0.01). The highest LAB population (p < 0.01) at 106 cfu/g FM was found in CSP fermented with L. casei and molasses. In conclusion, the current study shows that CSP treated with L×U×M resulted in good preservation by recovering DM, a low number of aerobic bacteria, and greater LAB than other treatments, with the exception of the L×U×M addition. A 21-day fermentation period is advised because it produces products with greater levels of crude protein, lactic acid, acetic acid, and propionic acid.

A newly developed strain of Enterococcus faecium isolated from fresh dairy products to be used as a probiotic in lactating Holstein cows

The objective of this study was to determine the ability of an isolated strain (EGY_NRC1) or commercial (NCIMB 11181) Enterococcus faecium as a probiotic for lactating cows. Two experiments were conducted: In Experiment 1, the effects of three levels (1, 2, and 3 g/kg diet, DM basis) of isolated and commercial E. faecium on in vitro ruminal fermentation kinetics, gas, methane (CH₄) and nutrient degradability were determined. In Experiment 2, thirty multiparous Holstein cows (633 ± 25.4 kg body weight) with 7 days in milk, were randomly assigned to 3 treatments in a completely randomized design in a 60-day experiment. Cows were fed without any additives (control treatment) or supplemented with 2 g/kg feed daily of E. faecium EGY_NRC1 (contain 1.1 × 10⁹ CFU/g) or commercial E. faecium NCIMB 11181 (contain 2 × 10¹² CFU/g). Diets were prepared to meet cow's nutrient requirements according to NRC recommendations. Probiotic doses were based on the in vitro Experiment 1. Feed intake, digestibility, blood parameters and lactation performance were evaluated. In Experiment 1, the isolated E. faecium linearly and quadratically increased (P < 0.001) in vitro total gas production (TGP), the degradability of dry matter (dDM) and organic matter (dOM) while decreased (P < 0.05) methane (CH₄) percent of TGP, NH₃CH₄ production, and pH. The commercial E. faecium increased TGP and decreased (P < 0.01) CH₄ production, pH and increased the dDM and dOM, short chain fatty acids and ruminal NH₃-N concentration. In Experiment 2, the isolated E. faecium increased (P < 0.01) total tract digestibility of DM, neutral and acid detergent fiber, daily milk production and feed efficiency compared to the control treatment without affecting feed intake and milk composition. Moreover, the isolated E. faecium increased (P < 0.05) the proportion of C18:1 trans-9, C18:2 cis-9-12 and C18:2 trans-10 cis-12. Both isolated and commercial E. faecium improved (P < 0.01) organic matter, crude protein and nonstructural carbohydrates digestibility, increased serum glucose (P = 0.002) and decreased serum cholesterol (P = 0.002). Additionally, both E. faecium strains decreased C23:0 (P = 0.005) in milk. In conclusion, the use of E. faecium (isolated and commercial) at 2 g/kg DM of feed improved feed efficiency and production performance, with superior effects on animal performance from isolated E. faecium compared to the commercial one.

Feeding Thai Native Sheep Molasses Either Alone or in Combination with Urea-Fermented Sugarcane Bagasse: The Effects on Nutrient Digestibility, Rumen Fermentation, and Hematological Parameters

The purpose of this study was to find out how adding molasses to fermented sugarcane bagasse (FSB) alone or in combination with urea affected sheep’s rumen fermentation, hematological parameters, and ability to digest nutrients. Four Thai native sheep with an initial body weight (BW) of 20.87 ± 1.95 kg and 11 ± 1.0 months old were assigned to a 4 × 4 Latin square design with 4 periods of 14-d adaptation and 7 d of sample collection. Each treatment received a different combination of experimental roughage as follows: FSB without additives (T1), FSB + 10% molasses (T2), FSB + 20% molasses (T3), and FSB + 10% molasses + 3% urea (T4). The concentrate diet was fed twice daily at 2% BW, while roughage sources were provided ad libitum for each treatment. The crude protein (CP) digestibility in the T2 and T3 groups was higher (p < 0.05) than in the FSB group without additions, with the T4 group having the highest (p < 0.05). Although there were no significant differences in blood glucose, packed cell volume, ruminal pH, ammonia−nitrogen (NH3-N), propionic acid, or acetic acid, the plasma urea nitrogen (PUN) at 0 h was highest in the T4 group (p < 0.05) compared with the other groups. However, the proportion of butyric acid tended to be higher in all FSB groups with additives. Thus, the current experiment concluded that the addition of molasses alone or in combination with urea had positive effects on pH and LAB population, and including both together in FSB improved the CP digestibility of sheep. In conclusion, FSB with 10% molasses and 3% urea might be used as an alternate roughage source for ruminants without affecting the animal’s ruminal fermentation or hematological parameters.

Impact of Probiotics on Dairy Production Efficiency

There has been growing interest on probiotics to enhance weight gain and disease resistance in young calves and to improve the milk yield in lactating animals by reducing the negative energy balance during the peak lactation period. While it has been well established that probiotics modulate the microbial community composition in the gastrointestinal tract, and a probiotic-mediated homeostasis in the rumen could improve feed conversation competence, volatile fatty acid production and nitrogen flow that enhances the milk composition as well as milk production, detailed changes on the molecular and metabolic level prompted by probiotic feed additives are still not understood. Moreover, as living biotherapeutic agents, probiotics have the potential to directly change the gene expression profile of animals by activating the signalling cascade in the host cells. Various direct and indirect components of probiotic approaches to improve the productivity of dairy animals are discussed in this review.

Effect of Feeding Discarded Durian Peel Ensiled with Lactobacillus casei TH14 and Additives in Total Mixed Rations on Digestibility, Ruminal Fermentation, Methane Mitigation, and Nitrogen Balance of Thai Native–Anglo-Nubian Goats

The objective of this study was to evaluate the effect of fermented discarded durian peel with Lactobacillus casei TH14, cellulase, and molasses separately or in combination in total mixed rations on feed utilization, digestibility, ruminal fermentation, and nitrogen utilization in growing crossbreed Thai Native–Anglo-Nubian goats. Five crossbreed Thai Native–Anglo-Nubian goats (50%) at 9 to 12 months of age and 20 ± 1 of body weight (BW) were assigned to a 5 × 5 Latin square design. Evaluated treatments were fermented discarded durian peel without additives (FDP), fermented discarded durian peel with 5% of molasses (FDPM), fermented discarded durian peel with 2% of cellulase (FDPC), fermented discarded durian peel with 1.0 × 105 cfu/g fresh matter of L. casei TH14 (FDPL), and fermented discarded durian peel with 5% of molasses and 1.0 × 105 cfu/g fresh matter of L. casei TH14 (FDPML). This study showed that acid detergent fiber intake was different (p < 0.05) between goats fed FDP and those fed FDPLM, 0.24 g/d and 0.20 g/d, respectively. The FDPML ration had significantly (p < 0.05) greater apparent nutrient digestibility and a better propionate concentration compared with other treatments. FDPML treatment significantly (p < 0.05) decreased the acetate-to-propionate ratio, methane production, and urinary nitrogen. Therefore, treated discarded durian peel with molasses and L. casei TH14 in combination could add 25% of dry matter into the diet for growing goats without a negative impact.

Rhodaneses Enzyme Addition Could Reduce Cyanide Concentration and Enhance Fiber Digestibility via In Vitro Fermentation Study

The use of cyanide-containing feed (HCN) is restricted because it causes prussic acid poisoning in animals. The objective of this study was to see how adding rhodanese enzyme to an HCN-containing diet affected gas dynamics, in vitro ruminal fermentation, HCN concentration reduction, and nutrient digestibility. A 3 × 4 factorial arrangement in a completely randomized design was used for the experiment. Factor A was the three levels of potassium cyanide (KCN) at 300, 450, and 600 ppm. Factor B was the four doses of rhodanese enzyme at 0, 0.65, 1, and 1.35 mg/104 ppm KCN, respectively. At 96 h of incubation, gas production from an insoluble fraction (b), potential extent (omit gas) (a + b), and cumulative gas were similar between KCN additions of 300 to 450 ppm (p > 0.05), whereas increasing KCN to 600 ppm significantly decreased those kinetics of gas (p < 0.05). Supplementation of rhodanese enzymes at 1.0 to 1.35 mg/104 ppm KCN enhanced cumulative gas when compared to the control group (p < 0.05). Increasing the dose of rhodanese up to 1.0 mg/104 ppm KCN significantly increased the rate of ruminal HCN degradation efficiency (DE) by 70% (p < 0.05). However, no further between the two factors was detected on ruminal fermentation and in vitro digestibility (p > 0.05). The concentration of ammonia-nitrogen (NH3-N) increased with increasing doses of KCN (p < 0.05), but remained unchanged with varying levels of rhodanese enzymes (p > 0.05). The in vitro dry matter digestibility (IVDMD) was suppressed when increasing doses of KCH were administered at 600 ppm, whereas supplementation of rhodanese enzymes at 1.0–1.35 mg/104 ppm KCN enhanced IVDMD (p < 0.05). Increasing doses of KCN affected reduced total volatile fatty acids (TVFA) concentration, which was lowest when 600 ppm was added (p < 0.05). Nevertheless, the concentration of TVFAs increased when rhodanese enzymes were included by 1.0–1.35 mg/104 ppm KCN (p < 0.05). Based on this study, it could be concluded that supplementation of rhodaneses enzyme at 1.0–1.35 mg/104 ppm KCN could enhance cumulative gas, digestibility, and TVAF, as well as lowering ruminal HCN concentration.

Ruminal Fermentation, Milk Production Efficiency, and Nutrient Digestibility of Lactating Dairy Cows Receiving Fresh Cassava Root and Solid Feed-Block Containing High Sulfur

This study evaluates the effects of fresh cassava root (CR) and a solid feed-block containing sulfur (S-FB) on fermentation in the rumen, feed utilization, milk yield, and milk composition in lactating dairy cows. Four Holstein-Friesian cows with 470 ± 50.0 kg body weight (BW), 10 ± 2 kg day−1 average milk yield, and 112 ± 15 days-in-milk were studied. A 2 × 2 factorial combination was arranged in a 4 × 4 Latin square design to evaluate the treatment-related effects. The treatments were obtained from a combination of two factors: (1) levels of CR at 10 g kg−1 BW (CR-1) and 15 g kg−1 (CR-1.5) and (2) levels of sulfur supplementation in solid feed-block at 20 g kg−1 (S-FB-2) and 40 g kg−1 (S-FB-4). The results showed that CR and S-FB had no interaction effect on feed intake, digestibility, fermentation, blood metabolites, milk yield, or its composition. Feeding CR up to 15 g kg−1 of the BW significantly increased (p < 0.05) the milk fat concentration while it decreased (p < 0.05) the somatic cell count. The S-FB-4 of the sulfur significantly (p < 0.05) increased the acid detergent fiber when compared with the S-FB-2 of the sulfur. CR could be fed up to 15 g kg−1 of BW with S-FB containing high sulfur (40 g kg−1) in dairy cows without a negative impact.

In Vitro Fermentation Characteristics and Methane Mitigation Responded to Flavonoid Extract Levels from Alternanthera sissoo and Dietary Ratios

Two experiments were conducted under this study: Experiment 1 was to study production yield, chemical composition, and in vitro degradability of Brazilian spinach (Alternanthera sissoo; BS) leaf and leaf + leaf-stalk at various maturity ages of 15, 30, 45, and 60 days after plantation and regrowth and Experiment 2 was to evaluate the effect of flavonoid extract from BS leaf and leaf + leaf-stalk and dietary ratios on ruminal gas production, fermentation characteristics, and in vitro degradability. Experiment 1 showed that maturity ages after planting and regrowth increased, the yield significantly increased. Increasing maturity ages significantly (p < 0.05) increased neutral detergent fiber and acid detergent fiber content and decreased crude protein content, total flavonoid (TF) content, and degradability for both leaf and leaf + leaf-stalk. Maturity ages from 15 to 30 days after plantation and regrowth resulted (p < 0.05) the highest TF content and degradability for both leaf and leaf + leaf-stalk. Thus, BS leaf and leaf + leaf-stalk samples from 15 to 30 days of age were used for flavonoid extraction and used in the Experiment 2. Experiment 2 was conducted according to a 3 × 5 factorial experiment. Three roughage to concentrate (R:C) ratios at 50:50, 40:60, and 30:70 were used, and five levels of flavonoid extract (FE) at 0, 10, 20, 30, and 40 mg of substrate dry matter (DM) were supplemented. Experiment 2 showed that R:C ratio and FE had an interaction effect only on acetate to propionate ratio. Varying R:C ratios significantly increased (p < 0.05) in vitro DM degradability, total volatile fatty acids (VFA), and propionate (C3) concentration. FE supplementation linearly (p < 0.05) increased total VFA and C3 concentration and decreased methane production and protozoal population. This study could conclude that FE from BS could effectively modulate ruminal fermentation and decrease methane production. However, in vivo study needs to elucidate in order to validate the present results.

Growth performances, nutrient digestibility, ruminal fermentation and energy partition of Thai native steers fed exclusive rice straw and fermented sugarcane bagasse with Lactobacillus, cellulase and molasses

The study aimed to evaluate the effect of sugarcane bagasse feeding treated with Lactobacillus casei TH14 (L. casei TH14), cellulase and molasses (BG) on nutrient digestibility, ruminal fermentation, energy partition and growth performances of Thai native steers compared to conventional feeding of rice straw (RS). Eight Thai native steers (144 ± 19.5 kg of initial body weight) were randomly allocated to two roughage sources in a completed randomized design: RS (n ꞊ 4) and BG (n ꞊ 4). The feeding trial lasted for 90 days plus 21 days for treatment adaptation. The results showed that the BG group showed (p < 0.05) greater intake (2.34 vs 2.02 kg/day), total intake (3.90 vs 3.55 kg/day) and average daily gain (0.27 vs 0.23 kg/day) while feed conversion ratio was lower compared to RS group. The BG group had a greater (p < 0.05) organic matter and acid detergent fibre intake than the RS group as well as dry matter and neutral detergent fibre digestibility. The steers fed RS and BG were significantly (p < 0.05) different for total volatile fatty acids and propionic acid at 4 h after offering the diet. The intake of nitrogen (g/day) and apparent nitrogen absorption was significantly (p < 0.05) higher for BG than the RS group while nitrogen excretion in faeces was significantly lower in RS than the BG group. BG group showed significantly (p < 0.05) greater gross energy intake and digestible energy partition when compared to the RS group. In conclusion, feeding BG enhanced feed utilization, growth performance, ruminal fermentation, nitrogen utilization and energy utilization.

Influence of chitosan sources on intake, digestibility, rumen fermentation, and milk production in tropical lactating dairy cows

The aim of study was to compare the influence of chitosan sources (commercial chitosan vs chitosan extract) on rumen fermentation, methane (CH₄) emission, and milk production in tropical lactating dairy cows. Six lactating Holstein-Friesian crossbreeds (410 ± 5 kg, 120 ± 21 day-in-milk) were arranged in a 3 × 3 replicated Latin square design. In addition to control, a 2% chitosan extract supplement and a 2% commercial chitosan supplement of dry matter intake were the treatments. The results denoted that no significant differences on daily dry matter, nutrients, or estimated energy intake were noted when cows received different sources of chitosan. Nutrient digestibility was not influenced differently by extraction-based or commercial chitosan supplements. The pH, temperature, ammonia nitrogen, blood urea, and microbial count were similar among treatments. The different sources of chitosan supplements did not change the totals of volatile fatty acids, acetate, and butyrate; in contrast, different chitosan sources influenced (P<0.05) propionate content. The ruminal acetate to propionate ratio was markedly (P<0.05) reduced with chitosan supplement, but no change appeared between sources of chitosan. At 4 h after feeding, the methane estimation significantly decreased with the addition of chitosan supplementation (P<0.05) compared to the control group. The purine derivatives and microbial protein synthesis were not altered by the treatments. No significant differences existed on milk yield, milk composition, or milk urea nitrogen when cows received different sources of chitosan (P>0.05). In summary, supplementing extracted chitosan showed more potential than did the commercial chitosan for enhancing economic efficiency and recycling shrimp residues, therefore, reducing environmental waste.