Dry Yeast Research Articles

Study of the Possibility of Honey Wine Production Using New Active Dry Yeasts and Yeasts Derivatives

The current article is dedicated to the study of the possibility of obtaining alcoholic beverages made by fermenting natural honey (honey wine) using different types of dry active yeast and yeast autolysis derivatives. The data obtained from the results of the research will be interesting both from the scientific and production point of view and allow us to conclude that the selected yeasts can be used for the production of such alcoholic beverages.

Effect of some growth stimulators on productivity, chemical and biological properties of Coleus amboinicus Lour. Cultivated under desert conditions

During the two successive seasons, 2020 and 2021, this investigation was carried out on Coleus amboinicus to study the effect of spraying some plant stimulators on growth, yield, active constituents, and biological activities. The experiment included six foliar spray treatments (control, moringa extract, blue green algae extract, compost tea, active dry yeast extract, and Azolla extract). The applications were arranged in a randomized complete block design with three replicates. The measured data involved growth and yield parameters (plant height, fresh weight of herb per plant, fresh yield of herb per hectare, dry weight of herb per plant, and dry yield of herb per hectare), chemical parameters (essential oil percent, oil content per plant, oil yield per hectare, oil composition, total phenolic content, total flavonoid content), and biological activities (antioxidant and anticancer). The results represented that spraying C. amboinicus with all stimulators significantly increased growth, yield, essential oil percent, oil content per plant, and oil yield per hectare over control. The significant promising treatment was sprayed with blue green algae extract, which recorded the best traits. Moreover, the results showed that using blue green algae extract revealed the highest total phenolic content in the plant while utilizing compost tea represented the highest total flavonoid content. Consequently, using compost tea enhanced in vitro antioxidant and anticancer activities of C. amboinicus.

A Research on the Comparative Effect of Active Dry Yeast and Inactivated-Stabilized Probiotic Yeast (Thepax) Added at Different Levels to Diets on Broiler Performance

This experiment was conducted to determine the effect of active yeast (AY) and inactive-stabilized yeast (Thepax) supplementation to the rations in different levels on broiler performance. In the experiment carried out according to the randomized plot design, there were 5 different treatment groups as control group (Group 1), 0.1% Thepax (Group 2), 0.2% Thepax (Group 3), 0.1% AY (Group 4) and 0.2% AY (Group 5). In the experiment, the effects of active and inactive yeasts on body weight gain (BWG), feed consumption, feed conversion rate, carcass weight (CW), carcass yield (CY), abdominal fat amount and mortality were investigated. In the present experiment, the final live weight, the cumulative feed consumption and feed conversion were insignificant. The statistical difference between the groups in the experiment was significant in carcass weight, but insignificant in the amount of abdominal fat and mortality rate. Inactive-stabilized yeast (Thepax 0.1%) was more effective than 0.2% AY on BWG. Only 0.1% Thepax increased the CW besides CY was high in 0.1%, 0.2% Thepax and 0.1% AY groups. It has been observed that active and inactive yeasts are used in broiler chickens without any problem.

Evaluation of extruded roughage with different additives in sheep diet

The purpose was to evaluate the effect of extruded roughage Foragge® with different additives on intake, digestibility nutrients and nitrogen balance of sheep. Twenty adults, non-pregnant ewes with average weight 68 kg were used. The treatments were extruded roughage with additives (essential oil, virginiamycin, unpurified inactive yeast, tannin and purified inactive yeast). The design was in randomized blocks. The means were contrasted by SNK test, and the fecal score was tested by the Kruskal Wallis test (1952), at 5% significance. There was no difference in the intake of dry matter, crude protein, nitrogen, water, water in relation to dry matter, neutral detergent fiber (NDF), and acid detergent fiber (p > 0.05). As well as the digestibility of dry matter, crude protein and neutral detergent fiber, the fecal weight, fecal nitrogen, retained nitrogen and nitrogen retained in relation to nitrogen ingested (p > 0.05). However, dry matter intake as a function of body weight and metabolic weight, urinary nitrogen, hemicellulose intake, and hemicellulose as a function of NDF, were higher in the Foragge Factor® treatment (p < 0.05). The inclusion of different additives in the extruded roughage improved nutritional parameters, without causing disturbances.

The effect of wheat variety, fermentation and incorporation of ingredients on the texture profile, colour and sensory attributes of whole wheat brea

Whole grain flour is gaining an increase in demand for its nutritive and health promotion values in different food products for human consumption worldwide. Whole flour from wheat grain varieties (Gihundo, Kibatsi, Nyaruka and Reberaho), spent coffee grounds (SCG), juices of lemon fruit (L) and rosemary leaves (R), and dough fermentation were assessed for their impact on the texture profile, colour and sensory attributes of bread. Wheat grains (sampled from the stores of Rwanda Agriculture and Animal Resources Development Board, Kinigi, Rwanda) were conditioned to 15.5% moisture content and were wholly milled. The mixture of 200 g whole wheat flour, 4% spent coffee grounds, 1% juice of lemon fruit and 1% juice of rosemary leaves were fermented by using 2% instant dry yeast at 34 °C, 60% relative humidity (RH) for 60 min and at 39 °C, 85% RH for 120 min, separately. The dough was baked at 180 °C for 20 min. Data were subjected to one-way analysis of variance using SAS System. Treatment means were separated using Tukey’s test and the least significant difference was accepted at p ≤ 0.05. The control bread was made for 60 min of fermentation without incorporation of SCG and LR. The control bread was harder than the bread containing SCG and SCG+LR with the same time of fermentation. The long fermentation and the inclusion of SCG and SCG+LR in doughs, caused the supplemented bread to have lower L*, a* and b* values than control bread. Low L*, a* and b* values indicate minimum darkness, redness and yellowness of bread. Aroma, taste and appearance of SCG+LR bread from doughs fermented for 120 min were the most liked. Whole wheat bread obtained satisfied consumers’ preferences. Therefore, the application of spent coffee grounds, juices of lemon fruit and rosemary leaves in bread making represents a good opportunity at low cost.

Interaction of Long-Chain Alcohol with Dry Yeast, Cholesterol, and Sea Firefly Luciferase

Background: A hand sanitizer containing alcohol, usually ethanol or isopropanol, is typically used for disinfection, but given that cholesterol is one of the main components of virus envelopes, long-chain alcohol may be more effective. To better understand the potential disinfection activity of long-chain alcohols, we studied their interactions with dry yeast, cholesterol, and sea firefly luciferase. Methods and Results: We measured, at 30oC and 39oC, the minimum inhibition concentration (MIC) of dry yeast fermentation and the stability of cholesterol and sea firefly luciferase with alcohols, diols, cetyltrimethylammonium chloride, and stearyltrimethylammonium chloride. The MIC decreased with the chain length at C≤12 for dry yeast and cholesterol with alcohol at 30oC. At C13 and higher, the cut-off region was observed. At 39oC, the cut-off region shifted to C15 and higher. The reduction of MIC was measured with the diol or sea firefly luciferase at C≤14. Conclusion: The presence of the cut-off region is suggested to be related to whether the alcohol is in the liquid state. For the liquid alcohol, the longer the chain length, the lower the MIC. This suggests a potential disinfection activity of long-chain alcohol.

The effect of high-penetrating emission on the growth, superoxide accumulation and ATP/ADP ratio in Saccharomyces cerevisiae

Many kinds of physical fields are able to affect biological activity, such as electromagnetic field, magnetic field, scalar wave, magnetic vector potential and so on. Some works investigated a high-penetrating emission (HPE) generated by a LED generator that can affect the conductivity of water and the growth of dry yeast. In this research, the biological effect of the HPE of LED generator on S. cerevisiae was studied. The results showed that this kind of HPE could promote the growth of S. cerevisiae. With the decrease of initial concentration and the extension of exposure time, the growth promoting effect of HPE increased significantly. When the initial cell concentration was 2 × 102 cell/ml and exposed for 24 h, the number of yeast cells increased by 19.5% compared with the control group. Further studies showed that adenosine triphosphate (ATP) content and the ratio of ATP and adenosine diphosphate (ADP, ATP/ADP ratio) of exposed cells were higher than those of unexposed cells, indicating that exposed cells had higher cell viability and energy status. In addition, the intracellular superoxide (O2−) content decreased significantly after the HPE exposed. In this study, the stainless steel box acts as a Faraday cage to shield the electromagnetic field, so the biological effect of the HPE is not produced by the electromagnetic field. Nevertheless, the mechanism of the HPE is still unknown and needs further research. This is the first report on the effect of HPE on mitochondrial parameters, contributing to further study on HPE and revealing potential for future medical applications.

BAKING QUALITY OF SPRING SOFT WHEAT AND TRITICALE DEPENDING ON THE FORECROP AND BACKGROUND OF CULTIVATION

The article presents data on the assessment of the baking quality of the varieties of spring soft wheat - Shortandinskaya 95 improved and spring triticale – Rosinka. The purpose of the work: a comparative assessment of bread quality made from spring wheat flour and spring triticale, depending on the forecrop and background of cultivation in Northern Kazakhstan. The sowing was carried out in the period 2018-2019 on the experimental areas of the “SPC GF named after A. I. Barayev” LLP. The influence of organic and traditional farming systems on the quality of the resulting products was studied. The organic farming system included the use of aboveground biomass of perennial grasses and legumes as organic fertilizer. Traditional - the use of mineral fertilizers: ammophos in a dose of P40, ammonium nitrate in a dose of N20, N40, N60 and N80. The test baking was carried out by the non-paired method with intensive kneading of the dough using dry yeast and 100 g of flour. The evaluation of the baking advantages of flour was carried out according to the method of the state variety testing with the determination of external  and internal signs of bread quality. Based on all the indicators, the overall baking score was obtained. It was found that the baking score of triticale bread is lower than that of wheat by 1- 1.5 points. In the years of research, the dependence of the quality of bread on the predecessor and the background of cultivation was noted. The advantage for the studied crops was the organic background, the best precursor for spring triticale was melilot, for spring soft wheat – granary.

Changed Rumen Fermentation, Blood Parameters, and Microbial Population in Fattening Steers Receiving a High Concentrate Diet with Saccharomyces cerevisiae Improve Growth Performance.

The effect of dry yeast (DY) (Saccharomyces cerevisiae) supplementation in a high-concentrate diet was evaluated for rumen fermentation, blood parameters, microbial populations, and growth performance in fattening steers. Sixteen crossbred steers (Charolais x American Brahman) at 375 ± 25 kg live weight were divided into four groups that received DY supplementation at 0, 5, 10, and 15 g/hd/d using a completely randomized block design. Basal diets were fed as a total mixed ration (roughage to concentrate ratio of 30:70). Results showed that supplementation with DY improved dry matter (DM) intake and digestibility of organic matter (OM), neutral detergent fiber (NDF), and acid detergent fiber (ADF) (p < 0.05), but DM and crude protein (CP) were similar among treatments (p > 0.05). Ruminal pH (>6.0) of fattening steer remained stable (p > 0.05), and pH was maintained at or above 6.0 with DY. The concentration of propionic acid (C3) increased (p < 0.05) with 10 and 15 g/hd/d DY supplementation, while acetic acid (C2) and butyric acid (C4) decreased. Methane (CH4) production in the rumen decreased as DY increased (p < 0.05). Fibrobacter succinogenes and Ruminococcus flavefaciens populations increased (p < 0.05), whereas protozoal and methanogen populations decreased with DY addition at 10 and 15 g/hd/d, while Ruminococcus albus did not change (p > 0.05) among the treatments. Adding DY at 10 and 15 g/hd/d improved growth performance. Thus, the addition of DY to fattening steers with a high concentrate diet improved feed intake, nutrient digestibility, rumen ecology, and growth performance, while mitigating ruminal methane production.

Nutritional Yeast Ferritin-Iron Complex: A Novel Source of Dietary Iron

Iron deficiency anemia (IDA) is the leading nutritional disorder in the world. Iron deficiency (ID) occurs commonly in the US, particularly among children and women and in the elderly. Its impact on quality of life includes decreased cognitive ability and increased fatigue. Thus, there is clearly a need for effective and economical approaches to providing adequate dietary iron. We introduce nutritional yeast (S. cerevisiae) technologically modified to express human H-ferritin as a potential source of dietary iron. The efficacy of the yeast ferritin complex (YFC) was tested in established rat and monkey models of ID. In the rat model of ID, YFC improved hemoglobin (Hgb), hematocrit (Hct) levels as well as plasma iron and transferrin saturation and liver and spleen iron concentrations. Moreover, the YFC achieved a larger effect on Hgb and Hct with consumption of less iron compared to ferrous sulfate over a similar period. In the monkeys, YFC supplemented diet significantly improved Hgb levels within one month and increased mean corpuscular volume (MCV) by two months. To demonstrate that the Fe in the YFC was utilized by RBCs, we used a labeled isotope approach and found Fe from the ferritin in the monkeys’ RBCs with 5 days of consumption. This is the first attempt to use H-ferritin homopolymer as a nutritional iron source. Previous data from our laboratory and others have established H-ferritin as a significant iron delivery protein to the brain. Thus, H-ferritin appears to have a novel function as an iron delivery protein independent from its cooperation with L-ferritin to form an iron storage protein.

Імунологічний профіль крові ярок за використання у раціонах про- і пребіотичних добавок

Goal. To study the effect of different doses of pro- and pre-biotic preparations of domestic production, made based on baker’s yeast Saccharomyces cerevisiae, when they are added to feeding rations of heifers, on the immunological status of the organism and the intensity of growth and development of animals. Methods. The study was conducted on heifers of Askanian meat-wool breeds aged from 11 to 12 months in the winter-spring stall period. The diet of animals in the control group consisted of meadow hay and standard mixed fodder K 83-19-89. Animals of the experimental groups in the mixed fodder received pro- and pre-biotic additions. The studies used zootechnical (determination of gross, average daily, and relative weight gain of animals), physiological and biochemical (determination of the number of leukocytes in the blood, the content of circulating immune complexes and lysozyme and bactericidal activity), analytical (analysis of literature sources on the topic of the article), and statistical computer programs in the processing the obtained data) methods. Results. It is established that the use in mixed fodder for heifers at the age of 11–12 months in the winter-spring stall period of the pro-biotic Enzymaktyv (EA) in doses of 0.4; 0.8 and 1.2% and pre-biotic Inactivated dry glutathione yeast (IDGY) in doses of 1.0, 1.4 and 1.8% by its weight has a positive effect on the level of immunological ingredients in the blood and productive qualities of animals. The addition of pro-biotic EA and pre-biotic IDGY in the specified doses to mixed fodder of heifers increases the number of leukocytes in their blood by 1.2–6.4%, reduces the content of medium molecular circulating immune complexes (CIC) in the blood by 5.3–12.8%, activates lysozyme and bactericidal activity in serum in 1.03–1.25 times. The use of pro-biotic EA in feed in the studied doses increases the gross increase in live weight of animals by 15–35%, and relative — by 14–32%, while the use of prebiotic IDGY — by 30–55 and 27–50% respectively. Conclusions. Taking into account the results of immunological parameters of blood and intensity of growth of animals, they recommend adding 0.8% pro-biotic EA and 1.4% pre-biotic IDGY to the feed for heifers in the winter-spring stall period.

Evidence for hybrid breakdown in production of red carotenoids in the marine invertebrate Tigriopus californicus.

The marine copepod, Tigriopus californicus, produces the red carotenoid pigment astaxanthin from yellow dietary precursors. This 'bioconversion' of yellow carotenoids to red is hypothesized to be linked to individual condition, possibly through shared metabolic pathways with mitochondrial oxidative phosphorylation. Experimental inter-population crosses of lab-reared T. californicus typically produces low-fitness hybrids is due in large part to the disruption of coadapted sets nuclear and mitochondrial genes within the parental populations. These hybrid incompatibilities can increase variability in life history traits and energy production among hybrid lines. Here, we tested if production of astaxanthin was compromised in hybrid copepods and if it was linked to mitochondrial metabolism and offspring development. We observed no clear mitonuclear dysfunction in hybrids fed a limited, carotenoid-deficient diet of nutritional yeast. However, when yellow carotenoids were restored to their diet, hybrid lines produced less astaxanthin than parental lines. We observed that lines fed a yeast diet produced less ATP and had slower offspring development compared to lines fed a more complete diet of algae, suggesting the yeast-only diet may have obscured effects of mitonuclear dysfunction. Astaxanthin production was not significantly associated with development among lines fed a yeast diet but was negatively related to development in early generation hybrids fed an algal diet. In lines fed yeast, astaxanthin was negatively related to ATP synthesis, but in lines fed algae, the relationship was reversed. Although the effects of the yeast diet may have obscured evidence of hybrid dysfunction, these results suggest that astaxanthin bioconversion may still be related to mitochondrial performance and reproductive success.

БІОКОНВЕРСІЯ МЕЛЯСИ ДО ЕТАНОЛУ РЕАКТИВОВАНИМИ ДРІЖДЖАМИ

The process of fermentation of beet molasses to ethanol using dry alcohol yeast Deltaferm AL-18, reactivated in wort with different dry matter content was studied. It is shown that the fermentative activity of these yeasts is higher than the generative one. The concentration of ethanol in the brew is maximum under the condition of reactivation of yeast in the wort (22 % CF). The density of yeast after fermentation decreases proportionally if the yeast is activated in the wort with a higher concentration.

Molecular brewing: The molecular structural effects of starch adjuncts on barley malt brewing performances

In this study, the effects of starch adjuncts with different fine molecular structures obtained by size-exclusion chromatography on the mashing and fermentation efficiencies of barley malts were investigated. Following fermentation, violate compounds of freshly-fermented beer samples were determined by headspace-solid-phase microextraction coupled with gas chromatography–mass spectrometry analysis (HS-SMPE-GC-MS). High performance liquid chromatography results showed that depending on their molecular structures, starch adjuncts addition significantly increased wort maltose and maltotriose content, whereas reducing the glucose content and thus both the ratios of glucose and maltotriose to that of the maltose. The whole fermentation by dry beer yeast was finished within the first 48 h and reached to equilibrium for the rest 72 h, represented by the stable soluble protein content. Results also showed that the addition of starch adjuncts resulted into increased alcohol content, which was mainly attributed to the altered glucose/maltose ratio. The HS-SPME-GC–MS results showed that whether or not with starch adjuncts addition, the composition of violate compounds were not significantly influenced, their content, on the contrary, were altered, represented by different peak heights. This study provides important information concerning the molecular effects of starch adjuncts on brewing performances of barley malts, and also provides a new pathway for choosing suitable types of adjuncts for making beer with better quality.

Development of simple and environmentally friendly soil solidification technique

We developed and studied a simple and environmentally friendly soil solidification technique utilizing bio-mineralization or bio-cementation process. The microorganism used for this technique was baker’s dry yeast. To adjust the pH of the soil and promote mineralization, agricultural fertilizer was used. Sandy soil was solidified by mixing the materials, adding water, and letting them cure. In terms of reproducible results, it was possible to produce solidified bodies with the same strength as cement-improved soil. In our study, only environmentally friendly materials have been used. Therefore, this technique can be applied not only for ground improvement, but also for other various applications such as sandy soil utilization.

288 Inclusion Effects of Quebracho (Schinopsis Balansaie) Extract and Active Dry Yeast (Saccharomyces Cerevisiae) in Beef Cattle Limit-fed a Grower Ration

Abstract Plant secondary metabolites (PSM) and yeast supplemented in growing cattle have been reported as improving dry matter digestibility (DMD) and reducing enteric methane emissions. This study aimed to evaluate the effect of combined supplementation with condensed tannin (CT; Schinopsis balansae) extract and active dry yeast (ADY; Saccharomyces cerevisiae) on fermentation dynamics, utilizing in vitro gas production (IVGP) technique. A 2 × 2 Latin square design was used to study fermentation patterns of four dietary treatments (CON- no CT and no ADY, ADY alone, CT alone or combined CT + ADY). Animals received daily CT at 1% DM and 10 g of ADY, respectively. On d 0, 7, 14, 21, 28, and 35 rumen inoculum was collected from 23 fistulated steers (284.3 ± 4.1 kg) four hours post-feeding. Samples were incubated under anaerobic conditions at 39oC for 48 h with 200 mg of a grower diet (14.8% CP, 40.6% NDF, 88.5% DM). Gas parameters were analyzed using a mixed linear statistical model. There was a day effect for total gas production (TGP; P &amp;lt; 0.001), non-fiber carbohydrate degradation (P = 0.031) and fractional degradation assuming an asymptote model (P = 0.015). Both asymptote and non-fiber fractional degradation rate estimates had an interaction between Day × TRT (P = 0.001 and 0.0104, respectively). Data were analyzed using polynomial contrasts showed a difference in non-fiber fractional rate of fermentation for CON × CT and CT × ADY (P = 0.052 and 0.054, respectively). This was also true if an asymptote model was assumed (P = 0.0 34 and 0.034, respectively). We concluded that combined supplementation of CT and ADY exhibited similar IVGP trends over time, this may be because animals only received a grower diet at 1.5% shrunk BW. Future studies should investigate the impact of combined supplementation on varying levels of concentrate diets.

The effects of feeding benzoic acid and/or live active yeast (Saccharomyces cerevisiae) on beef cattle performance, feeding behavior, and carcass characteristics.

Fifty-nine Angus-cross finishing steers were used to evaluate benzoic acid, active dry yeast (Saccharomyces cerevisiae), or a combination of benzoic acid and active dry yeast when supplemented in a high-grain finishing diet on live animal performance, feeding behavior, and carcass characteristics. Steers were fed a high-grain diet for the final 106 d of finishing. Treatments were as follows: no additional supplementation (CON), 0.5% benzoic acid (ACD), 3 g per head per day active dry S. cerevisiae (YST), or both 0.5% benzoic acid and 3 g/head per day S. cerevisiae (AY). Steers were weighed every 14 d, and ultrasound was performed for rib and rump fat thickness at the beginning (day 1), middle (day 57), and end (day 99) of the experiment. Insert feeding stations were used to collect individual feeding behavior data and DMI daily throughout. Blood samples were collected on days 21 and 22 and days 99–101 to assess plane of nutrition and metabolism. Ruminal fluid samples were collected by oral gavage 4 wk prior to slaughter. Carcass characteristics were examined at a federally inspected slaughter facility. Data were analyzed using PROC GLIMMIX of SAS with initial body weight (BW) as a covariate. Benzoic acid supplementation increased (P = 0.002) overall dry matter intake (DMI) compared to YST and CON steers, which may be due to a faster eating rate (P ≤ 0.008). Animal performance parameters (BW, average daily gain, feed conversion, and ultrasound fat depth) were not different (P ≥ 0.11) among treatment groups. Aspartate aminotransferase concentration was greatest (P ≤ 0.01) for YST steers, which may have been reflected in numerically greater liver abscesses. Carcass traits did not differ (P ≥ 0.33) among treatment groups. Ruminal pH was greater (P = 0.006) for ACD steers than AY steers (pH of 6.16 vs. 5.66, respectively), which indicated that there may be an interactive effect between benzoic acid and active dry yeast. To summarize, steers fed a high-grain finishing diet supplemented with benzoic acid, active dry yeast, or both benzoic acid and active dry yeast had similar growth performance and carcass characteristics compared to those without supplementation. However, the addition of benzoic acid alone increased DMI, variation in DMI, eating rate, and ruminal pH. Future studies are warranted to further investigate the impacts of benzoic acid on the ruminal environment of feedlot cattle.

The Effect of Different Cold Storage Period on Total Lipid Amount of Tenebrio molitor (Coleoptera: Tenebrionidae) Larvae

The ever-increasing world population indicates that it is inevitable to consider insects such as Tenebrio molitor, which are used as live food and even human food in some countries, as an alternative food source. Especially T. molitor larvae are a source of food with high nutritive value for including high lipid and protein. The main material of this study was T. molitor cultures. Flour:wheat flour (250 g: 250 g) in a ratio of 1:1 was used as food. 25 g wheat germ and 5 g dry yeast was put in it. Larvae at stages 13-15th were grouped as control and trial groups and kept for 5, 10, 15 and 20 days at specified temperatures. This study seeks answer to the question “will the insect continue to keep its lipid sources during the periods in which it is kept in the cold, or will it continue to use its energy sources since the physiological adaptations it develops are not enough?” This study evaluates the total lipid amount and percentages of T. molitor larvae stored in refrigerator for different periods. Total lipid amount and percentages of the larvae stored in the cold for 5, 10 and 15 days were found to be higher when compared with the control group. A tendency to decrease was observed in larvae kept for 20 days. As a result, it is recommended for producers not to keep in the refrigerator for more than 15 days. Otherwise, it should be considered that there may be a decrease in important energy and food sources.

Successful rearing of Bactrocera dorsalis on a semi-solid artificial diet

The fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae) is an economically important polyphagous pest and has been adjudged as one of the five most devastating fruit flies throughout the world. These flies are highly polyphagous, multivoltine, fertile, and mobile which makes it very difficult to manage these insect-pests. Finding a simple, cheap, and appropriate rearing approach of B. dorsalis is an urgent need to support research activities for management of this pest. This investigation is meant to evaluate various artificial diets and to find out the most suitable artificial diet for mass rearing of this pest. In the present studies, five different artificial diets were used for the rearing of B. dorsalis at Punjab Agricultural University, Ludhiana during 2018–19. A semi-solid artificial diet consisting of 1000 ml water, 40 g dry yeast, 120 g sucrose, 1 g sorbic acid, 6.6 g ascorbic acid, 10 g agar, 10 g soya peptone, 0.1 g ampicillin, and 0.03 g tetracycline was considered most suitable for successful rearing of B. dorsalis. The biological parameters of B. dorsalis were used to validate the diet quality and rearing procedure. This diet supported the development of B. dorsalis efficiently and was used further for evaluation of RNA interference (RNAi) studies. This artificial diet and suggested rearing procedure will help to maintain culture of B. dorsalis and further help to study biology and management of other insect-pests species as well.

Active dry yeast supplementation improves the growth performance, rumen fermentation, and immune response of weaned beef calves.

The objective of this experiment was to investigate the potential benefits of active dry yeast (ADY) on the growth performance, rumen fermentation, nutrient digestibility, and serum parameters of weaned beef calves. Thirty Simmental crossbred male calves (body weight = 86.47 ± 4.41 kg and 70 ± 4 d of age) were randomly divided into 2 groups: control (CON) (fed basal ration) and ADY (fed basal ration and 5 g/d ADY per calf). The dietary concentrate-to-roughage ratio was 35:65. All the calves were regularly provided rations 3 times a day at 07:00, 13:00, and 19:00 and had free access to water. The experiment lasted for 60 d. The average daily gain of ADY group was higher (P = 0.007) than that of the CON group, and the ratio of feed intake to average daily gain in the ADY group was reduced (P = 0.022) as compared to the CON group. The concentration of ruminal ammonia-N was higher (P = 0.023) in the CON group than that in the ADY group, but an opposite trend of microbial protein was found between the 2 groups. Also, the ruminal concentrations of propionate and butyrate were higher (P < 0.05) in the ADY group than those in the CON group. Calves fed ADY exhibited higher (P < 0.05) crude protein and neutral detergent fiber digestibility. Supplementation of ADY increased (P < 0.05) the contents of glucose, glutathione peroxidase, superoxide dismutase, immunoglobulin A, immunoglobulin M, and interleukin 10 in the serum of calves, but an opposite trend was observed in malondialdehyde, interleukin 1 beta, and tumor necrosis factor alpha contents between the 2 groups. In conclusion, dietary supplementation with ADY could improve the growth performance, rumen fermentation, nutrient digestibility, antioxidant ability, and immune response of weaned beef calves.