Immune status and haemato-biochemical profile of buffalo calves supplemented with phytogenic feed additives rich in tannins, saponins and essential oils

Drying enhances the antioxidant activity of Allium mongolicum Regel through the phenylpropane and AA-MA pathway as shown by metabolomics

Fresh Allium mongolicum Regel (FA) and dried A. mongolicum Regel (DA) are significantly different in antioxidant activity. However, the relevant mechanisms have not yet been explored. We evaluated the antioxidant activities of two varieties of FA and DA and characterized their metabolites using targeted metabolomics. The effect of different metabolites on the antioxidant activity of A. mongolicum Regel was investigated by multivariate analysis. A total of 713 metabolites were detected in all samples. Pearson correlation analysis demonstrated that the key primary metabolites were directly and significantly correlated with the total phenolic content (TPC) and total flavonoid content (TFC), while the secondary metabolites were directly correlated with antioxidant activity. The higher antioxidant activity of DA may be mainly attributed to the higher TPC and TFC. This study revealed the potential mechanism by which drying enhances the antioxidant activity of A. mongolicum Regel.

Evaluation of oral supplementation of free and nanoencapsulated Minthostachys verticillata essential oil on immunological, biochemical and antioxidants parameters and gut microbiota in weaned piglets

Early weaning is an important stressor that impairs the piglet´s health, and essential oils appear as promising candidates to improve it instead of antibiotics. The aim of this study was to evaluate the effect of oral supplementation of free and nanoencapsulated Minthostachys verticillata essential oil (EO and NEO, respectively) on immunological, biochemical and antioxidants parameters as well as on gut microbiota in weaned piglets. EO was extracted by hydrodistillation and nanoencapsulation was performed by high-energy method using Tween 80 and Span 60 as surfactants. EO and NEO were chemically analyzed by gas chromatography-mass spectrometry (GC-MS). The cytotoxic effects of both EO and NEO was evaluated on Caco-2 cell line. For in vivo assay, male weaned piglets (age: 28 days, mean initial body weight: 11.63 ± 0.37 kg) were randomly distributed in six groups of six animals each (n = 6) and received orally EO (10.0 mg/kg/day) or NEO (2.5, 5.0 and 10.0 mg/kg/day), named hereinafter as EO-10, NEO-2.5, NEO-5 and NEO-10, for 30 consecutive days. Animals not treated or treated with surfactants mixture were evaluated as control and vehicle control. Subsequently, histological, hematological and biochemical parameters, cytokines production, oxidative markers, CD4+/CD8+ T cells and gut microbiota were evaluated. GC-MS analysis was similar in both EO and NEO. The NEO was more toxic on Caco-2 cells than EO. Oral supplementation of EO-10 or NEO-10 improved growth performance compared to control group NEO-2.5 or NEO-5 (p < 0.05) groups. NEO-2.5, NEO-5 and NEO-10 did not alter the morpho-physiology of digestive organs and decreased malondialdehyde (MDA) levels in liver compared to control (p < 0.05) or EO-10 groups (p < 0.05, p < 0.01). In addition, NEO-10 showed an increase in CD4+/CD8+ T cells ratio (p < 0.001), and induced the highest serum levels of IL-10 (p < 0.01). Serum triglycerides levels were significantly lower in animals treated with EO-10 or NEO-2.5, NEO-5 and NEO-10 compared to control group (p < 0.001). Gut microbiota analysis showed that NEO-10 favor the development of beneficial intestinal microorganisms to improve parameters related to early weaning of piglets. In conclusion, EO and NEO improved parameters altered by early weaning in piglets however, NEO was safer and powerful. Therefore, NEO should be further studied to be applied in swine health.

Phytogenic feed additives as natural antibiotic alternatives in animal health and production: A review of the literature of the last decade

The use of antibiotics in animal production raises great public safety concerns; therefore, there is an urgent need for the development of substitutes for antibiotics. In recent decades, plant-derived feed additives have been widely investigated as antibiotic alternatives for use in animal health and production because they exert multiple biological functions and are less likely to induce resistance development. This review summarizes the research history and classification of phytogenic feed additives and their main functions, potential modes of action, influencing factors, and potential negative effects. Further, we highlight the challenges in developing sustainable, safe, and affordable plant-derived antibiotic alternatives for use in livestock production.

Use of a commercial feed supplement based on diatom earth and yeast products on oxidative status and in vitro immune response in buffaloes during peripartum

The transition period is a critical metabolic phase for dairy ruminants, especially those with high production levels. In spite of this, little is still known about dairy water buffalo. The aim of this study was to evaluate the effect of a commercial feed additive based on diatomaceous earth and hydrolyzed yeasts on health status, milk quality, and immune response of buffalo cows during the transition period. Eighty healthy Water buffaloes (Bubalus bubalis) of Italian Mediterranean breed were included in the trial. They were subdivided into two groups: one group received the additive (n = 40) while the control group (n = 40) received a placebo. The trial lasted 120 d, from 60 d before calving to 60 d in milk. Blood samples were collected from each buffalo at -60 (60 d from the expected calving), -30, 0 (calving), +15, +30, and +60 d (respectively, i.e., 15, 30, and 60 d in milking). The biochemical as well as the oxidative profile, and the antioxidant power and enzymatic activity were evaluated in the samples obtained. Moreover, acute phase proteins, reactive proteins, and interleukin plasma levels were determined. Peripheral blood mononuclear cells (PBMCs) and monocytes were isolated and viability, reactive oxygen species (ROS), and reactive nitrogen species were measured on PBMC and monocytes. The introduction of additives enhanced the total antioxidant capacity and enzyme activity, while no differences were observed in oxidation products throughout the trial. Additionally, it significantly reduced the synthesis of ROS in polymorphonuclear cells, supporting a potential positive response in animals experiencing inflammation. The impact of oxidation on the products was not evident. Despite higher enzyme levels in plasma, this did not necessarily correspond to significantly increased enzymatic activity but rather indicated a higher potential. From these results, it was evident that the transition period in buffaloes differs notably from what reported in the literature for cows, probably due to the absence of common postpartum production diseases in dairy cows and lower metabolic challenges linked to lower milk production in buffaloes. Few parameters exhibited notable changes during the transition period in buffaloes, notably certain antioxidant enzymes, PBMC viability, PBMC ROS production, and Hp levels.

Utilizing intramammary Melaleuca alternifolia as an organic internal sealant for dry-off therapy in Murrah buffaloes

The effects of intramammary dry cow therapy based on the administration of 5% Melaleuca alternifolia tea tree essential oil (TTO) as an internal teat sealant to Murrah cows were evaluated. A longitudinal prospective and retrospective negative control study was performed using 12 buffaloes from a total of 20 Murrah buffaloes on an organic farm, with the cow used as a control for herself. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for treatments with pure oil (TTO) and medication containing 5% TTO (O5) were determined. The buffaloes were clinically examined, and the teats were evaluated using thermography and ultrasound. Udder health was monitored during the first 100 days in milk (DIM) using milk somatic cell count (SCC) and California mastitis test (CMT). Laboratory tests against standard strains Staphylococcus aureus ATCC®25,923™, Escherichia coli ATCC®25,922™, and wild bacterial strains showed maximum MIC values of 50 µL/mL for the TTO and O5 treatments. One wild-type S. aureus strain showed no MBC. No adverse effects were observed after the intramammary application of TTO. The CMT and SCC values were similar (P > 0.05) for all observations. The medication containing 5% TTO was effective in vitro and compatible with the intramammary tissue in vivo of Murrah buffaloes. TTO was safe, not inducing inflammatory processes or other modifications of the teat detectable by thermography or ultrasound. It was able to protect buffaloes during the dry period under field conditions, demonstrating potential use as a teat sealant for organic farms.

Effect of supplementation of fennel seed powder on intake, growth performance, gut health and economics in goats

The aim of this study was to evaluate the effect of fennel seed powder (FSP) at varying levels on intake, growth, gut health, body condition, body measurements and economics in post weaned male goats. For this experiment a total of 30 post weaned male kids of Barbari goats with statistically similar body weight (P = 0.575) and age (3-4 months) were randomly distributed in three comparable groups each having 10 kids. Three groups viz. control (no supplementation), T1 (0.5% of DM in diet) and T2 (1.0% of DM in diet) were formed and the study continued up to 5 months. Statistical analysis of results showed significant effect of FSP supplementation on intake, growth, body condition, and gut health and body measurements in goats of treatment groups. Significantly highest body weight (BW), average daily gain (ADG) and dry matter intake (DMI) (P < 0.001) was reported in T2 group, followed by T1 than control group goats. Further, feed conversion ratio (FCR), feed conversion efficiency (FCE%) and body condition score of treatment groups (T1 and T2) was improved significantly (P < 0.001) than control group goats. However, FCR and FCE% in T1 and T2 differed non- significantly (P > 0.05). Analysis of fecal samples indicated significantly higher (P < 0.001) fecal dry matter (FDM%), fecal consistency score (FS) in T1 and T2 group than control group whereas parasitic fecal egg count per gram (EPG) was significantly lower in T1 and T2 group than control group. However, EPG in T1 and T2 differed non- significantly (P > 0.05). Body measures differed significantly (P < 0.05) among groups. Economic evaluation of FSP supplemented showed that T1 and T2 group fetched INR 462 and 501 per goat on selling over control group (1USD = 82.54 INR). It can be concluded from this study that supplementation of FSP @ 1.0% of DM in diet may economically improve intake, growth, gut health, body condition, body measurements and economics in post weaned male Barbari goats.

Botanicals: A promising approach for controlling cecal coccidiosis in poultry

Avian species have long struggled with the problem of coccidiosis, a disease that affects various parts of the intestine, including the anterior gut, midgut, and hindgut. Among different types of coccidiosis, cecal coccidiosis is particularly dangerous to avian species. Chickens and turkeys are commercial flocks; thus, their parasites have remained critical due to their economic importance. High rates of mortality and morbidity are observed in both chickens and turkeys due to cecal coccidiosis. Coccidiostats and coccidiocidal chemicals have traditionally been added to feed and water to control coccidiosis. However, after the EU banned their use because of issues of resistance and public health, alternative methods are being explored. Vaccines are also being used, but their efficacy and cost-effectiveness remain as challenges. Researchers are attempting to find alternatives, and among the alternatives, botanicals are a promising choice. Botanicals contain multiple active compounds such as phenolics, saponins, terpenes, sulfur compounds, etc., which can kill sporozoites and oocysts and stop the replication of Eimeria. These botanicals are primarily used as anticoccidials due to their antioxidant and immunomodulatory activities. Because of the medicinal properties of botanicals, some commercial products have also been developed. However, further research is needed to confirm their pharmacological effects, mechanisms of action, and methods of concentrated preparation. In this review, an attempt has been made to summarize the plants that have the potential to act as anticoccidials and to explain the mode of action of different compounds found within them.

Effects of fennel (Foeniculum vulgare) seed powder addition during early lactation on performance, milk fatty acid profile, and rumen fermentation parameters of Holstein cows

Introduction

Aromatic and herbal plants usage as feed additives have become a new tendency in dairy cows’ nutrition to enhance animal performance. This experiment was performed to study the effects of supplementing fennel seed powder (FSP) to diets during early lactation on performance, milk fatty acid (FA) profile, and rumen fermentation of Holstein dairy cows.

Methods

Twenty-four primiparous Holstein dairy cows (10 ± 3 d in milk, 30 ± 2.1 Kg of milk/d, 610 ± 31 Kg body weight; mean ± SE) were balanced for actual milk yield and calving date (n = 8 per treatment) in a complete randomized design. Animals were allocated randomly to diets containing 0 g/d (0FSP), 25 g/d (25FSP), or 50 g/d (50FSP) FSP, individually top-dressed over the total mixed ration. The experimental period was 45 d consisting of the first 15 d for adaptation and the final 30 d for data collection and sampling.

Results and discussion

Dry matter intake responded quadratically to FSP feeding, and cows fed 25FP treatment had greater DMI than 0FSP treatment. The average ruminal pH value decreased linearly as FSP increased in diets. Ruminal valerate and isovalerate proportion increased linearly as FSP inclusion in diets increased, while acetate proportion decreased and acetate:propionate ratio tended to decrease linearly. Increasing FSP in diets linearly increased serum glucose, globulin, and total protein concentrations. Milk yield increased linearly as FSP inclusion in diets increased, whereas milk composition was unaffected. Increasing FSP in diets linearly increased de novo and mixed FA and decreased preformed FA in milk. Dietary treatments did not affect saturated FA, whereas unsaturated FA, mono and poly unsaturated FA linearly decreased with increasing FSP inclusion in diets. Moreover, the content of C18:0 tended to decrease, and C18:1 cis-9 decreased linearly as FSP inclusion increased. Also, increasing the FSP level in diets decreased linearly non-esterified fatty acids and acetone concentrations in the milk. It could be concluded that FSP addition at 50 g/d could enhance performance of early lactating cows.

The effect of dietary inclusion of Artemisia sieberi leaves on growth performance, feeding behaviors, ruminal fermentation, feed digestibility, and blood hemato-biochemical profile of growing male lambs

The objective of this study was to investigate the impacts of replacing alfalfa hay with Artemisia sieberi leaves (ASL) on growth performance, feeding behaviors, total tract feed digestibility, ruminal fermentation as well as blood cells, and biochemical parameters. A total of 21 Kermani male lambs (average body weight (BW) of 25.2 ± 0.9 kg) were randomly divided into three groups and offered the following treatments: (1) basal diet (65% concentrate and 35% alfalfa hay as forage source), (2) ASL inclusion at 25% of forage source (8.75% of TMR, ASL25), and (3) ASL addition at 50% of forage source (17.5% of TMR, ASL50). The experiment lasted for 64 days, including 14 days of adaptation and 50 days of data collection. Dietary ASL inclusion decreased lambs' feed consumption (6.7 and 2.8% reduction in ASL25 and ASL50, respectively, p < 0.05) without affecting water intake, final BW, daily weight gain, and feed conversion ratio. Moreover, feeding behaviors, including time spent for eating, ruminating, and chewing activities, were uninfluenced by the dietary ASL addition on days 25 and 50 of the experiment. Based on the data provided, the substitution of alfalfa hay with ASL resulted in an increase in the digestibility of dry matter, organic matter, and neutral detergent fiber (p < 0.05). In addition, the ruminal fluid of ASL-fed lambs had a lower molar proportion of acetate and a higher proportion of propionate compared to that of the control animals (p < 0.05), whereas other volatile fatty acids (VFA) and total VFA were not different between the experimental groups. Blood hematocrit, hemoglobin, red cells, white cells, and their differentiation, platelets, glucose, total protein, albumin, globulin, triglyceride, calcium, phosphorus, aspartate aminotransferase, and alanine aminotransferase, urea, total antioxidant capacity, and malondialdehyde remained unchanged when ASL was included in the diet. Regardless of the slight decrease in dry matter intake, the lack of adverse effects of dietary ASL addition on growth performance, feeding behaviors, rumen fermentation, and blood hemato-biochemical parameters, along with positive impacts of ASL on propionate production and total tract feed digestibility, suggest that Artemisia sieberi leaves can be considered as a potential alternative feed resource for small ruminants.

Effects of Neem (Azadirachta indica) Leaf Powder Supplementation on Rumen Fermentation, Feed Intake, Apparent Digestibility and Performance in Omani Sheep

The objective of the present study was to evaluate the potential of the dietary addition of neem (Azadirachta indica) leaf powder (NLP) when compared to monensin (MON) on ruminal fermentation, feed intake, digestibility, and performance of growing lambs. Eighteen Omani lambs (22.8 ± 2.18 kg of body weight (BW)) were equally divided into three groups (n = 6 lambs/group) for 90 days. Animals were fed an ad lib basal diet consisting of Rhodes grass (Chloris gayana) hay (600 g/kg) and a concentrated mixture (400 g/kg) offered twice daily. Experimental treatments were control (basal diet without supplements); MON (control plus 35 mg/kg DM as a positive control); and NLP (control plus 40 g/kg DM). Lambs fed NLP had reduced ruminal ammonia nitrogen concentrations, protozoal counts, total volatile fatty acid, and blood urea nitrogen concentrations compared to the control. Compared to MON, lambs fed NLP had increased ruminal acetate and decreased propionate proportions. Inclusion of NLP in the diet increased blood total protein, globulin, and liver enzyme concentrations in comparison with the control, which was similar to MON. The lamb's final BW and average BW gain were also increased with the NLP relative to the control. Further, adding NLP to the diet increased the digestibility of crude protein compared to the control diet. In conclusion, adding NLP to the diet with 40 g/kg DM could be used as a promising phytogenic supplement for growing lambs with no detrimental effects on the ruminal fermentation profile, nutrient intake, or digestibility.

Dietary Galla Chinensis tannic acid supplementation in the diets improves growth performance, immune function and liver health status of broiler chicken

This experiment was conducted to investigate the effects of Galla Chinensis tannic acid (TA) on growth performance, immune function, and liver health status in broilers. A total of 288 1-day-old Arbor Acres broiler chickens were randomly divided into two groups in a 42-days study. The two groups were a basal diet (CON group) and a basal diet supplemented with 300 mg/kg Galla Chinensis tannic acid (TA group). The results showed that the TA group had significantly decreased feed-to-gain ratio (F/G) throughout the experiment (P < 0.05). The levels of total protein, albumin, low density lipoprotein, high density lipoprotein, urea, total cholesterol, and glucose in the TA group were significantly higher than in the CON group (P < 0.05). In addition, the serum immunoglobulin G, immunoglobulin M, and complements (C3, C4) levels in the TA group were significantly higher than those in the CON group (P < 0.05). Compared with the CON group, the hepatic interleukin-6, interleukin-18, NLRs family pyrin domain containing 3 (NLRP3), caspase-1, and caspase-3 in the TA group were significantly decreased (P < 0.05). Besides, TA group had significantly lower mRNA expression levels of toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 (MyD88), nuclear factor-kappa B (NF-κB), and NLRP3 in liver (P < 0.05). The TA group had significantly higher the mRNA expression levels of Bcl-2 than CON group in liver (P < 0.05). Moreover, TA group tended to decrease Bax/Bcl-2 ratio in liver (P < 0.10). To sum up, dietary supplemented with microencapsulated TA from Galla Chinensis had beneficial effects on growth performance, immune function, and liver health status in broilers. The protective role of TA from Galla Chinensis in liver health of broilers might be related to the inhibition of hepatic apoptosis and pyroptosis via inactivation of TLR4/MyD88/NF-κB signaling pathway.

Minthostachys verticillata Griseb (Epling.) (Lamiaceae) essential oil orally administered modulates gastrointestinal immunological and oxidative parameters in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Minthostachys verticillata (Griseb.) Epling (Lamiaceae) is a plant used in folk medicine for digestive or respiratory disorders. In addition, it is incorporated as condiment, in foods, as beverage flavoring or mate. The ethnopharmacological interest of M. verticillata resides in its essential oil (EO). Part of group has demonstrated the immunomodulatory ability of EO giving this oil a biological potential not known until that moment and conducted studies to evaluate their possible application in diseases of veterinary interest. However, the immunomodulatory effects of EO administered orally have not been fully characterized.

AIM OF THE STUDY

This study evaluated the impact of EO oral administration on gastrointestinal and immune health through measurement of immunological and oxidative parameters in mice.

MATERIAL AND METHODS

The EO was extracted from the leaves, slender stems and flowers of M. verticillata by hydrodistillation and chemical analyzed by gas chromatography-mass spectrometry (GC-MS). Prior to in vivo study, the cytotoxic effect of EO was determined using the human colon carcinoma Caco-2 cell line. For in vivo study, three groups of male Balb/c mice (n = 3) were orally administered with saline solution (control group) and EO (5 or 10 mg/kg/day) during 10 consecutive days. Subsequently, histological and hematological parameters, cytokines production, oxidative markers and CD4⁺ and CD8⁺ T cells were evaluated.

RESULTS

The chemical analysis of EO revealed the presence of a high content of monoterpenes, being the main pulegone (76.12%) and menthone (14.28%). The EO oral administration improved mice growth performance and modulated systemic adaptive immune response by increasing in the total leukocyte number. A high percentage of CD4⁺ T cells were observed whereas the number of CD8⁺ T cells was not altered. EO did not alter the morpho-physiology of intestine and improved total antioxidant capacity by decreasing MDA concentrations. In addition, EO decreased the IL-6 levels and increased in the IL-4 and IL-10 concentrations.

CONCLUSION

Results indicate that M. verticillata EO modulate inflammatory and oxidative parameters constituting a natural alternative which could be applied to improve gastrointestinal and immune functionality in animals.

Supplementing a Phytogenic Feed Additive Modulates the Risk of Subacute Rumen Acidosis, Rumen Fermentation and Systemic Inflammation in Cattle Fed Acidogenic Diets

Feeding with high-concentrate diets increases the risk of subacute ruminal acidosis (SARA). This experiment was conducted to evaluate whether supplementing a phytogenic feed additive based on L-menthol, thymol, eugenol, mint oil (Mentha arvensis) and cloves powder (Syzygium aromaticum) (PHY) can amend the ruminal fermentation profile, modulate the risk of SARA and reduce inflammation in cattle. The experiment was designed as a crossover design with nine non-lactating Holstein cows, and was conducted in two experimental runs. In each run, cows were fed a 100% forage diet one week (wk 0), and were then transitioned stepwise over one week (0 to 65% concentrate, wk adapt.) to a high concentrate diet that was fed for 4 weeks. Animals were fed diets either with PHY or without (CON). The PHY group had an increased ruminal pH compared to CON, reduced time to pH < 5.8 in wk 3, which tended to decrease further in wk 4, reduced the ruminal concentration of D-lactate, and tended to decrease total lactate (wk 3). In wk 2, PHY increased acetate, butyrate, isobutyrate, isovalerate, and the acetate to propionate ratio compared to CON. Phytogenic supplementation reduced inflammation compared to CON in wk 3. Overall, PHY had beneficial effects on ruminal fermentation, reduced inflammation, and modulated the risk of SARA starting from wk 3 of supplementation.

Fresh Phyllanthus emblica (Amla) Fruit Supplementation Enhances Milk Fatty Acid Profiles and the Antioxidant Capacities of Milk and Blood in Dairy Cows

The objective of this study was to investigate the effect of a diet supplemented with fresh amla fruit as a natural feed additive on blood metabolic parameters, milk antioxidant capacity, and milk fatty acid (FA) proportions in lactating dairy cows. Eight ruminally cannulated mid-lactation dairy cows were used in a repeated crossover design. The first group of four cows received total mixed ration (TMR) feed without fresh amla fruit (control group). The remaining four cows sequentially supplemented fresh amla fruit (FAF) at three levels (200, 400, then 600 g/d) (treatment group) at 14-day intervals. In second period, control and treatment groups were exchanged. The first ten days were adjusted to diet adaptation for each sub-period, and the last four days for sampling milk and blood. A total of 514 metabolites were detected from FAF using UPLC-ESI-MS/MS. The five main metabolites in FAF were phenolic acids (22%), flavonoids (20%), lipids (20%), amino acids and derivatives (9%), and tannins (7%). Amla fruit supplementation reduced total saturated fatty acid and the omega-6/omega-3 ratio at 200 or 400 g/d FAF dose compared to controls. In addition, amla fruit increased unsaturated FA, such as C_20:5 (Eicosapentaenoic acid, EPA) and C_22:6 (docosahexaenoic acid, DHA), and branched-chain FA in a dose-dependent manner at 200 or 400 g/d compared to controls. In addition, amla fruit increased the antioxidant capacity biomarkers in the blood, such as superoxide dismutase (SOD) and albumin; this confirms that amla fruit is an excellent antioxidant, inhibiting reactive oxygen species’ (ROS) metabolism, and can thereby protect cells from oxidative stress. Moreover, the most remarkable improvement of ferric reducing-antioxidant power (FRAP) and total antioxidant capacity (TAC) in milk was recorded at 400 g/d FAF doses compared to controls. Therefore, fresh amla fruit doses for lactating cows at 400 g/d on an as-fed basis can be used as an alternative additive feed in dairy cow diets to improve antioxidant capacity, protein efficiency, butter quality, and to produce more desirable milk fatty acid profiles for human consumption.

Fennel and Ginger Improved Nutrient Digestibility and Milk Yield and Quality in Early Lactating Egyptian Buffaloes

The supplementation with herbal and medicinal plants to animals showed positive effects on feed digestion, performance and animal’s health. Fifteen multiparous Egyptian buffaloes (537 ± 18.1 kg body weight), 7 days after parturition, were randomly assigned to 3 treatments in a quintupled 3 × 3 Latin square design in a 63-day experiment. Each experimental period lasted 21 days (15 days of adaptation + 7 days for measurements and samples collection). Buffaloes were assigned according to their previous milk production, weight and parity to study the effect of fennel (Foeniculum vulgare) or ginger (Zingiber officinale) supplementation on feed utilization and lactational performance. Buffaloes were fed a basal diet of concentrates, berseem clover and rice straw in a ratio of 60:30:10 dry matter (DM) basis. The first group was fed the basal diet with no additive as the control treatment, while other buffaloes were fed on the basal diet supplemented with 75 g fennel or ginger/buffalo daily. Additives supplementation did not affect feed intake; however, fennel followed by ginger improved (P<0.05) dry matter, organic matter, crude protein and neutral detergent fiber digestibilities compared to the control. Without affecting blood chemistry, fennel and ginger supplementation improved (P<0.05) production of milk and energy corrected milk, fat concentration and milk energy content and output. Fennel followed by ginger decreased the somatic cell count (P=0.035) compared with the control. Fennel and ginger improved feed efficiency (P<0.05) compared with the control. Fennel increased the proportion of milk trans-10, cis-12 C18:2 (P=0.028), total conjugated linoleic acid without affecting other fatty acids. It is concluded that fennel or ginger at 75 g/buffalo/d improved nutrient digestibility and milk production of lactating buffaloes. Fennel improved milk nutritive value more than ginger.

Tannic Acid Exhibits Adjuvant Activity by Enhancing Humoral and Cell-Mediated Immunity Against BSA as a Protein Antigen

BACKGROUND

Immunization or vaccination is the process of inducing artificial immunity against an antigen taking advantage of the mechanisms of immunological memory. Current vaccines include substances known as adjuvants, which tend to improve the immunogenicity of the antigen, reduce the antigen quantity employed, and boost the immune response in weak responders. Unfortunately, only a few vaccine adjuvants are approved for human use.

OBJECTIVE

Thus, the objective of this study was to investigate the effect of Tannic acid on humoral and cell-mediated immunity against bovine serum albumin (BSA) as a protein antigen in Wistar rats.

METHOD

In order to establish the Tannic acid concentration to test it as an adjuvant, the lethal dose 50 and maximum non-toxic dose were calculated through cytotoxicity and hemolytic assays with J774 A.1 cell line and rat erythrocytes by resazurin reduction method and UV/vis spectrophotometry. Thirty Wistar rats were divided into 5 groups that included two controls without antigen and three treatment groups of adjuvants plus BSA as a protein antigen. The rats were immunized in a 30-day scheme. Blood samples were collected for humoral immunity analysis by means of immunoglobulin quantification, isotyping and antigen-antibody precipitation inhibition analysis. Rat peritoneal macrophages and splenocytes were isolated for cell-mediated immunity analysis by means of nitric oxide quantification from adjuvant stimulated peritoneal macrophages and lymphocytes proliferation assay.

RESULTS

Tannic acid was capable of increasing the immunogenicity of the antigen; besides, it was able to stimulate cell-mediated immunity by means of increased lymphocyte proliferation. Moreover, Tannic acid improved the humoral response by means of increased specific antibodies titers. These activities may be attributed to pattern recognition receptors stimulation.

CONCLUSION

Tannic acid was considered biocompatible when tested in vivo because the concentration tested did not show cytotoxicity or hemolytic effect, and there was no detrimental effect observed on the animals' health. These results show Tannic acid as a promising candidate for vaccine adjuvant.

Top-dressing of chelated phytogenic feed additives in the diet of lactating Friesian cows to enhance feed utilization and lactational performance

The present experiment evaluated the inclusion of chelated phytogenic feed additives mixture in the diet of lactating cows for the first 3 months of lactation. A week before calving, thirty multiparous Friesian cows were divided into three treatments in a complete randomized design and fed a basal diet without supplementation (Control treatment), or the control diet supplemented with chelated phytogenic additives at 3 g (PHY3 treatment), or at 6 g/cow/d (PHY6 treatment). Menthol, levomenthol, β-linaloolm, anethole, hexadecanoic acid and pmenthane were the principal compounds identified in the additives mixture. Milk production, total solid, protein, fat, and lactose were increased with PHY3, but decreased by PHY6 (P<0.01). Whereas the PHY3 treatment increased (P<0.05) milk contents of Ca and Zn, PHY3 and PHY6 treatments increased (P<0.05) milk Fe and Mn concentrations. Though the PHY3 treatment increased (P<0.05) nutrient digestibility, the PHY6 treatment decreased (P<0.05) the digestibility of organic matter, crude protein and neutral detergent fiber. The PHY3 treatment increased (P<0.05) ruminal volatile fatty acids (VFA) concentration and proportional acetate and propionate and decreased butyrate, while the PHY6 treatment decreased ruminal VFA concentration and proportional acetate. The PHY3 treatment increased (P<0.05) serum total protein, glucose, total antioxidant capacity, and the concentrations of Ca and Zn. Both PHY3 and PHY6 treatment decreased (P<0.05) the concentrations of serum triglycerides, and cholesterol. Daily inclusion of 3 g/cow of chelated feed additives mixture in diet of lactating cows improved milk production and ruminal fermentation, but additives dose of 6 g/cow/d had negative impact on cows’ performance.

Phytogenic feed additives mixture enhances the lactational performance, feed utilization and ruminal fermentation of Friesian cows

The assay aimed to evaluate the effect of feeding a recently developed phytogenic feed additives mixture in diets of lactating Friesian cows (n = 30; 514 ± 10.1 kg body weight) for 3 months. Cows were stratified into three groups of 10 cows each and fed a control diet alone or the control diet supplemented with the additives mixture at 3 g (PHY3) or 6 g (PHY6)/cow daily. Menthol, levomenthol, β-linaloolm, anethole, hexadecanoic acid and p-menthane were the principle compounds identified in the additives mixture. The PHY3 increased (p < 0.01) intake and nutrient digestibility. PHY3 and PHY6 increased (p < 0.01) ruminal pH, total volatile fatty acids, propionate and acetate. PHY3 and PHY6 improved serum total protein and antioxidant capacity and decreased the concentrations of serum urea-N, triglycerides, total lipids, cholesterol and malondialdehyde (p < 0.05). PHY3 increased milk production and milk content of total solids, protein, lactose and fat. Both PHY3 and PHY6 did not affect mineral concentrations in blood or milk. It is concluded that the inclusion of 3 g/cow/d of feed additives mixture in the lactating Friesian cows diet enhanced milk production and feed utilization, with negative effects observed with increasing the dose of additives mixture to 6 g/cow daily.