Effect of zinc sources and experimental conditions on zinc balance in growing wethers

Three experiments were conducted with growing wethers to evaluate apparent excretion and retention of Zn from various sources. In Exp. 1 and 2, Zn-ethylene diamine (ZE), Zn hydroxychloride (ZHYD), Zn-lysine/glutamate (ZAA), and Zn-glycinate (ZG) were used and ZnSO4 (ZS), Zn hydroxychloride (ZHYD), Zn-lysine/glutamate (ZAA), and Zn-glycinate (ZG) were used in Exp. 3. In Exp. 1, 8 wethers were used in a replicated 4 × 4 Latin Square design. In Exp. 2 and 3, 40 wethers were used in a randomized block design. In Exp. 1, each period (total 4 periods) consisted of 14-day diet adaptation and 4 days of total collection of feces and urine. In Exp. 2 and 3, wethers received a basal diet for 14 days and received experimental diets for 9 days (diet adaptation), followed by 4 days of total collection of feces and urine. Total collection was conducted in wooden metabolic cages. All data were analyzed using the MIXED procedure of SAS as a Latin square design for Exp. 1 and a completed randomized block design for Exp. 2 and 3. In all experiments, dry matter intake did not differ among treatments except that it tended to be different in Exp. 2. In Exp. 1, no difference in Zn excretion (88%) and retention (11%) as proportion of Zn intake was observed among Zn sources. In Exp. 2, total tract digestibility of crude protein was greater (P < 0.01) for ZAA than ZE and ZG (82.0 vs. 79.1 and 77.8%, respectively) and greater (P < 0.01) for ZHYD than ZG (80.2 vs. 77.8%). However, total tract digestibility of neutral detergent fiber was low (on average 16%) for all treatments with no difference among treatments in Exp. 2. Apparent excretion and retention of Zn as proportion of Zn intake did not differ among treatments, and Zn retention (~1.4% of Zn intake) was very low for all treatments. In Exp. 3, ZHYD and ZAA had greater retention of Zn (17.8 vs. 1.5%; P = 0.01) than ZG. Fecal Zn excretion was greater (97.3 vs. 81.2%; P = 0.01) for ZG vs. ZHYD and ZAA, and Zn retention for ZG was only 1.5% of Zn intake. In conclusion, potential increases in Zn absorption and retention were observed for ZHYD and ZAA compared with ZS and ZG in Exp. 3 and these differences were not found in Exp. 1 and 2. Experiment 1 used a Latin square design and Exp. 2 used a diet containing largely undigestible fiber. These experimental conditions may have affected Zn metabolism in wethers. Inconsistent results on Zn balance for ZG among the experiments warrant further studies regarding its bioavailability.

Effect of replacement of forage sorghum silage with biomass sorghum silage in diets for dairy heifers

This trial aimed to analyze the replacement of forage sorghum silage (FS silage) with biomass sorghum silage (BRS 716 silage) in diets for heifers ¾ Holstein x ¼ Zebu on their nutrient intake and digestibility, nitrogen balance, microbial production, feeding behavior, and animal performance. Eight heifers with average age 18±4 months (mo) and average body weight (BW) 271 ± 57 kg were used. The experimental design was double-Latin square, 4×4, being four diets, four experimental periods and four animals. Four experimental diets with 0, 33, 67 and 100% substitution of forage sorghum silage with biomass sorghum silage were used. The roughage:concentrate ratio in the total dry matter (DM) of the diets was 75:25. The fraction “b” of DM was higher in the BRS 716 silage. There was no difference (p> 0.05) for dry matter intake (DMI; p = 0.45) and total digestible nutrients intake (p = 0.76). The dry matter digestibility (DMD), crude protein, ether extract and neutral detergent fiber increased linearly with the inclusion of BRS 716 silage. The feeding times, ruminating and idle have not been changed (p > 0.05). The replacement of FS silage with BRS 716 silage did not modify the average daily weight gain (ADG; p > 0.05; mean 1.30 ± 0.025 kg). Biomass sorghum silage can replace up to 100% forage sorghum silage in the diets of ¾ Holstein x ¼ Zebu heifers.

Controlling critical mistag-associated false discoveries in metagenetic data

Metagenetic methods are commonplace within ecological and environmental research. One concern with these methods is the phenomenon of critical mistagging, where sequences from one sample are erroneously inferred to have originated from another sample due to errors in the attachment, PCR replication or sequencing of sample-specific dual-index tags. For studies using PCR-based library preparation on large sample sizes, the most cost-effective approach to limiting mistag-associated false detections involves using an unsaturated Latin square dual-indexing design. This allows researchers to estimate mistagging rates during sequencing but the statistical procedures for filtering out detections using this mistag rate have received little attention. We propose a straightforward method to limit mistag-associated false discoveries during metabarcoding applications. We analyzed two Illumina metabarcoding datasets produced using unsaturated Latin square designs to explore the distribution of mistagged sequences across dual-index combinations on a per taxon basis. We tested these data for conformity to the assumptions that 1) mistagging follows a binomial distribution [i.e., X ~ B(n, p)] where p, the probability of a sequence being mistagged, varies minimally across taxa and 2) mistags are distributed uniformly across dual-index combinations. We provide R functions that estimate the 95th percentile of expected mistags per dual-index combination for each taxon under these assumptions. We show that mistagging rates were consistent across taxa within the datasets analyzed and that modelling mistagging as a binomial process with uniform distribution across dual-index combinations enabled robust control of mistag-associated false discoveries. We propose that this method of taxon-specific filtering of detections based on the maximum mistags expected per dual-index combination should be broadly accepted during metagenetic analysis, provided that experimental and control sequence abundances per taxon are strongly correlated. When this assumption is violated, data may be better fit by assuming that the distribution of mistags across combinations follows Poisson characteristics [i.e., X ~ Pois(𝜆)], with 𝜆 empirically estimated from the abundance distribution of mistags among control samples. We provide a second R function for this case, though we have yet to observe such a dataset. Both functions and demonstrations associated with this work are freely available at https://github.com/RTRichar/ModellingCriticalMistags.

The Effect of Yeast and Roughage Concentrate Ratio on Ruminal pH and Protozoal Population in Thai Native Beef Cattle

The objective of this research is to investigate the effect of yeast (Saccharomyces cerevisiae) adding and roughage-to-concentrate ratio (R:C ratio) on nutrients utilization, rumen fermentation efficiency, microbial protein synthesis, and protozoal population in Thai native beef cattle. Four Thai native beef cattle, weighing an average of 120 ± 10 kg live weight, were randomly assigned to four dietary treatments using a 2 × 2 factorial arrangement in a 4 × 4 Latin square design. Factor A was the level of roughage-to-concentrate ratio (R:C ratio) at 60:40 and 40:60; factor B was the levels of live yeast (LY) supplementation at 0 and 4 g/hd/d; urea–calcium-hydroxide-treated rice straw were used as a roughage source. Findings revealed that total intake and digestibility of dry matter (DM), organic matter (OM), and crude protein (CP) were increased (p < 0.05) by both factors, being greater for steers fed a R:C ratio of 40:60 supplemented with 4 g LY/hd/d. Ruminal ammonia nitrogen, total volatile fatty acid (VFA), and propionate (C3) were increased (p < 0.05) at the R:C ratio of 40:60 with LY supplementation at 4 g/hd/d, whereas rumen acetate (C2) and the C2 to C3 ratio were decreased (p < 0.05). With a high level of concentrate, LY addition increased total bacterial direct counts and fungal zoospores (p < 0.05), but decreased protozoal populations (p < 0.05). High-concentrate diet and LY supplementation increased nitrogen absorption and the efficiency of microbial nitrogen protein production. In conclusion, feeding beef cattle with 4 g/hd/d LY at a R:C ratio of 40:60 increased C3 and nutritional digestibility while lowering protozoal population.

Effect of Vacuum Level and Pulsation Parameters on Milking Efficiency and Animal Welfare of Murciano-Granadina Goats Milked in Mid-Line and Low-Line Milking Machines

The Murciano-Granadina goat breed has been described as a slow milking breed. As milking machine parameters can affect milk extraction in terms of yield and time employed, two experiments of one-month duration were performed with 88 goats in Latin square design to find the best combination of these parameters. One of them was carried out in a mid-line milking machine and one in a low-line milking machine. For each of them, two vacuum levels (36 and 40 kPa), two pulsation rates (90 and 120 cycles/min) and two pulsator ratios (50 and 60%) were used and milking efficiency, sanitary status of the mammary gland, milk cortisol, and teat end status were evaluated. Results showed that in milking machines installed in mid- and low-line, the use of 40 kPa system vacuum, 60% pulsator ratio and 90 or 120 cycles/min pulsation rate achieved optimum milking fractioning and efficiency. In the case of low-level milking machines, a similar combination with 36 kPa not only showed worse milking fractioning values, but also provided better values of teat end status and cortisol level.

Supplementing a blend of magnesium oxide to feedlot cattle: effects on ruminal, physiological, and productive responses

This experiment evaluated ruminal, physiological, and productive responses of feedlot cattle consuming a corn-based finishing diet that included different levels of a magnesium oxide (MG) blend. Yearling cattle (58 heifers and 62 steers) were ranked by sex and initial body weight (BW; 407 ± 3.1 kg), and allocated to 4 groups of 30 animals each. Groups were housed in 1 of 4 drylot pens (30 × 12 m) equipped with GrowSafe automated feeding systems (Model 6000E, 4 bunks/pen) during the experiment (d -14 to 117). On d 0, groups were randomly assigned to receive a total-mixed ration without (CON; n = 30) or with the inclusion (as-fed basis) of MG at 0.25% (MG25; n = 30), 0.50% (MG50; n = 30), or 0.75% (MG75; n = 30) until slaughter on d 118. Individual feed intake was recorded daily, and BW were recorded every 14 d and prior to slaughter (d 117). Blood samples were collected on d 0, 28, 56, 84 and 112, and hair samples were collected on d 0, 56 and 112 from the tail-switch. On d 42, 8 rumen-cannulated steers (BW = 492 ± 8.0 kg) were housed with yearling cattle (1 pair/pen). Pairs rotated among groups every 14 d, resulting in a replicated 4 × 4 Latin square design (n = 8/treatment; d 42 to 98). Rumen pH was measured on d 7 and 14 of each period (0800, 1200, 1600 and 2000 h). Orthogonal contrasts were used to determine if inclusion of MG (0, 0.25, 0.50, or 0.75% of the diet) yielded linear or quadratic effects, and to explore overall effect of MG supplementation (CON vs. MG25 + MG50 + MG75). No treatment differences were noted (P ≥ 0.31) for BW gain, feed intake, or feed efficiency. Cattle supplemented with MG tended have less carcass marbling (P = 0.07) compared with CON. Inclusion of MG linearly increased (P &lt; 0.01) mean plasma concentrations of magnesium, and tended to linearly decrease (P = 0.09) mean plasma concentrations of haptoglobin. Cattle supplemented with MG had greater (P &lt; 0.01) mean plasma concentrations of cortisol compared with CON. Hair cortisol concentration did not differ between treatments on d 56 (P ≥ 0.25), and linearly decreased (P &lt; 0.01) with MG inclusion on d 112 (treatment × day; P = 0.02). Inclusion of MG linearly increased (P = 0.03) mean rumen pH, but these outcomes were mostly noted during the last two sampling of the day (treatment × hour; P = 0.02). Collectively, supplemental MG was effective in controlling rumen pH in cattle receiving a corn-based finishing diet, but without improvements in feedlot performance and carcass merit.

Design, Formulation and Physicochemical Evaluation of Clotrimazole Chewing Gum

Background: Oral candidiasis is widespread in the patients with immunodeficiency diseases. Chewing gums are considered as mobile drug delivery systems that affected locally or systemically via the oral cavity. This study aimed to develop and evaluate the formulation of clotrimazole chewing gums for patients having oral candidiasis. Materials and Methods: Fourteen formulations (F) were designed by Design-Expert, version 7. These formulations were different in the amount of gum bases and sweeteners. Gum bases of elvasti, 487, stick, and fruit C were heated up to 70°C. Clotrimazole powder, sugar, liquid glucose, glycerin, mannitol, xylitol, and maltitol as well as different flavoring agents were added to the gum bases at 40°C. Content and weight uniformity, organoleptic properties evaluation, releasing the active ingredient in the phosphate buffer pH, 6.8, and taste evaluation were analyzed by Latin square analysis. Also, the mechanical test was done on F13 and F14 formulations. Results: F14 was the best formulation in terms of organoleptic properties. This formulation had suitable size, hardness, softness, and lack of adhesion to teeth. F14 formulation released 89% and 97% of clotrimazole after 30 and 45 minutes, respectively. F14 content uniformity and weight variations were 9.83±0.086 mg and 1.14±0.09 g, respectively. F14 evaluation of mechanical properties showed Young’s modulus about 0.32 MPa, and yield point occurred at the stress of 0.599 MPa and strain of 4.1%. Conclusion: F14 was chosen according to its physicochemical and organoleptic properties. F14 had adequate hardness, lack of adhesion to the teeth, suitable size, and best drug release. Tutti Frutti was a proper flavoring agent for clotrimazole gum formulations.[GMJ.2021;10:e1084]

The Effects of Fermentation of Low or High Tannin Fava Bean-Based Diets on Glucose Response, Cardiovascular Function, and Fecal Bile Acid Excretion during a 28-Day Feeding Period in Dogs: Comparison with Commercial Diets with Normal vs. High Protein

We have shown that feeding dogs fava bean (FB)-based diets for 7 days is safe and FB flour fermentation with Candida utilis has the potential to decrease FB anti-nutritional factors. In the present study, the effects of 28-day feeding of 4 different FB-based test dog foods containing moderate protein (~27% dry matter (DM)) were compared with two commercial diets with normal protein (NP, grain-containing, ~31% DM protein) or high protein (HP, grain-free, ~41% DM protein). Health parameters were investigated in beagles fed the NP or HP diets or using a randomized, crossover, 2 × 2 Latin square design of the FB diets: unfermented high-tannin (UF-HT), fermented high-tannin (FM-HT), unfermented low-tannin (UF-LT), and fermented low-tannin (FM-LT). The results showed that fermentation increased glucose tolerance, increased red blood cell numbers and increased systolic blood pressure, but decreased flow-mediated vasodilation. Taken together, the overall effect of fermentation appears to be beneficial and improved FB nutritional value. Most interesting, even though the HP diet was grain-free, the diet did contain added taurine, and no adverse effects on cardiac function were observed, while glucose tolerance was impaired compared to NP-fed dogs. In summary, this study did not find evidence of adverse cardiac effects of pulses in ‘grain-free’ diets, at least not in the relatively resistant beagle breed over a 28-day period. More importantly, fermentation with C. utilis shows promise to enhance health benefits of pulses such as FB in dog food.

Protein Source and Intake Effects on Diet Digestibility and N Excretion in Horses—A Risk of Environmental N Load of Horses

Six Finnhorse mares were used in a digestibility trial, in which six typical horse diets were compared. The diets were: (A) haylage 100%; (B) hay 100%; (C) hay 70% and oats 30%; (D) hay 70% and soybean meal + oats 30%; (E) hay 70%, rapeseed meal + oats 30% and (F) hay 70 %, linseed meal + oats 30%. The trial was conducted according to an unbalanced 6 × 4 Latin square design with four 3-week experimental periods. The experimental period consisted of 17-day preliminary feeding which was followed by a 4-day total faecal and urine collection periods to evaluate N excretion. The digestibilities of DM (p < 0.001) and OM (p < 0.001) in the haylage-only diet were lower compared to the other diets. The supplemental protein feeds improved the diet digestibility of CP (p = 0.002) compared to a hay + oats diet. Furthermore, the DM (p = 0.019), OM (p = 0.006), and CP (p = 0.016) digestibilities of the soya-supplemented diet were better than those of the rapeseed- and linseed-supplemented diets. Faecal excretion was greater for haylage (19.3 kg fresh faeces and 3.6 kg DM/day) and hay (18.7 kg fresh faeces and 3.6 kg DM/day) diets (p < 0.001) compared with the other diets. Urine excretion was also greater for forage-only diets compared with diets including protein supplements. Horses excreted 14.0 L urine/day on haylage-only diet (p = 0.026) and 14.3 L/day on a hay-only diet (p = 0.003). Horses excreted more nitrogen in their urine than in dung. N excretion differed between the diets. Horses on a haylage-only diet excreted 51.6 g N in faeces /day and on hay-only diet 51.4 g N/day. On the other hand, when protein content in forages increased, N excretion via urine increased (haylage vs. dried hay). Horses excreted less N in urine with hay-only diet than with haylage-only or protein-supplemented diets (p < 0.001). When N excreted in faeces and urine was counted together, horses excreted less N with a hay-only diet (p < 0.001) than with a supplemented one (oats and/or protein feeds). The results showed that feed choices affected the amount of nitrogen excreted. Feeding recommendations should consider not only the horse category and work level, but also the protein source. When good quality protein is fed, smaller N intakes can be applied to reduce the N excretion via urine and dung. At the farm level, improved understanding of feed quality, as well as feeding planning and practices, is a way to decrease the risk of N leaching and evaporation.