The effect of oral metformin on insulin sensitivity in insulin-resistant ponies

Metformin may be an effective therapeutic option for insulin-resistant (I-R) horses/ponies because, in humans, it reportedly enhances insulin sensitivity (SI) of peripheral tissues without stimulating insulin secretion. To determine the effect of metformin on insulin and glucose dynamics in I-R ponies, six ponies were studied in a cross-over design by Minimal Model analysis of a frequently-sampled intravenous glucose tolerance test (FSIGT). Metformin was administered at 15 mg/kg bodyweight (BW), orally, twice-daily, for 21 days to the metformin-treated group. The control group received a placebo. A FSIGT was conducted before and after treatment. The Minimal Model of glucose and insulin dynamics rendered indices describing SI, glucose effectiveness (Sg), acute insulin response to glucose (AIRg) and the disposition index (DI). The body condition score (BCS), BW and cresty neck score (CNS) were also assessed. There was no significant change in SI, Sg, AIRg, DI, BW, BCS or CNS in response to metformin, or over time in the control group. There were no measurable benefits of metformin on SI, consistent with recent work showing that the bioavailability of metformin in horses is poor, and chronic dosing may not achieve therapeutic blood concentrations. Alternatively, metformin may only be effective in obese ponies losing weight or with hyperglycaemia.     

Subsequent nitrogen utilisation and soil water distribution as affected by forage radish cover crop and nitrogen fertiliser in a corn silage production system

Forage radish is a unique winter cover crop that is relatively new but becoming rapidly adopted in temperate, humid North America. Little is known about how the use of this cover crop may influence subsequent nitrogen availability, soil water accumulation in the soil profile in corn silage production system. In this present work, the average nitrogen uptake by silage corn increased significantly by 11.6% in cover plots compared with the no-cover control plots. The recovery efficiency and agronomic efficiency of applied nitrogen in silage corn declined in cover plots compared to no-cover plots. The average soil water storage in cover plots was significantly higher than in the control after corn sowing and at the harvest stage. With increasing nitrogen application level, the average corn grain yield increased significantly at 56 and 112 kg N ha^?1 by 13.1% and 39.8%, respectively. Planting a forage radish cover crop can facilitate growth of silage corn and markedly improve total nitrogen uptake of corn. Consideration should be given to nitrogen application rate and also to avoiding excessive nitrogen input in the subsequent crop following a cover crop, thereby truly improving subsequent fertiliser use efficiency.     

Experimental infection of cats (Felis catus) with Tritrichomonas foetus isolated from cattle

Tritrichomonas foetus is recognized as the causative agent of venereal trichomoniasis in cattle. It is characterized by embryonic and early fetal death and post-coital pyometra, and feline trichomoniasis, manifest as chronic, large bowel diarrhea. Many of the infected cats are less than 2 years old and specific routes of transmission remain unknown. We recently demonstrated that feline isolates of T. foetus can successfully infect heifers, resulting in pathologic changes similar, but not identical to those previously reported as representative of bovine trichomoniasis. In this study, we experimentally infected six cats less than 1 year of age with a bovine (D-1) isolate of T. foetus and one cat with a feline (AUTf-1) isolate of T. foetus. Within 2 weeks, the cat infected with the feline (AUTf-1) isolate was culture positive for trichomonads in weekly fecal samples. At the end of 5 weeks, only one cat infected with the bovine (D-1) isolate was fecal culture positive for trichomonads. At necropsy, the intestine of each cat was removed and divided into five sections (ileum, cecum, anterior, medial and posterior colon). Contents from each section were collected and cultured. The cat infected with the feline (AUTf-1) isolate was culture positive in the ileum, cecum, medial and posterior colon. Two cats infected with the bovine (D-1) isolate were culture positive in the cecum only. Additionally, each intestinal section was submitted to a pathologist for histopathological examination. The combined results indicate that there are demonstrable differences between the feline (AUTf-1) and bovine (D-1) isolates regarding their infectivity in cats.     

Studies on ‘zinc deficiency syndrome’ in Black Bengal goats (Capra hircus) fed with fodder (Andropogon gayanus) grown on soil treated with an excess of calcium and phosphorus fertilizer

Overliming and excessive application of superphosphate caused a zinc deficiency in the soil and so reduced the uptake of zinc by fodder plants. Bucks reared on such fodder had significantly (p<0.01) less zinc in their hair compared with controls and suffered from conditioned zinc deficiency syndrome with a significant (p<0.01) loss of body weight, stunted growth, alopecia, lethargy, abnormal (kyphotic) gait, anorexia, digestive and respiratory problems. Oral supplementation with zinc sulphate very rapidly improved these conditions to near normality. Histological examination of samples of skin and testis from the zinc-deficient bucks revealed formation of excessive keratin, retention of nuclei in the stratum corneum and reduction in the width of the stratum granulosum in the skin, while samples of testis indicated degenerative changes, including atrophy of the seminiferous tubules, hyperplasia of the germinal epithelium and thickening of the walls of blood ve ssels.     

Vitamin D3 supplementation of beef steers increases longissimus tenderness.

The objectives of these experiments were to determine 1) the effectiveness of supplemental vitamin D3 (VITD) on altering plasma and muscle calcium levels, 2) whether VITD supplementation improves Warner-Bratzler shear force (WBS) values of steaks from feedlot beef steers, and 3) the tenderness response curve of longissimus steaks from steers supplemented with VITD. In Exp. 1, 20 crossbred steers were assigned randomly to one of four treatment diets consisting of either 0, 2.5, 5.0, or 7.5 x 106 IU of VITD per day for 10 d. Blood samples were obtained daily during this supplementation period and 5 d thereafter (d 11 to 15). Between d 6 and 13, a linear increase (P < .01) in ionized plasma calcium concentrations was observed in steers supplemented with VITD. Compared to unsupplemented steers, serum calcium concentrations of the steers receiving 7.5 x 106 IU of VITD per day were increased 8 to 48%. In Exp. 2, longissimus samples from crossbred steers (n = 118) that were supplemented with either 0 or 5 x 106 IU of VITD per day for 7 d were obtained and aged for 7, 14, or 21 d. Following the initial 7-d postmortem aging period, VITD supplementation lowered (P < .01) WBS (.58 kg) and increased sensory tenderness rating (.6 units) compared to cuts originating from unsupplemented steers. In Exp. 3, 44 steers were supplemented with either 0 or 7.5 x 106 IU of VITD per day for 10 d immediately prior to slaughter. Results indicated that plasma and longissimus calcium concentration were higher (P < .05) for steers that received supplemental VITD. Compared with unsupplemented cuts, VITD supplementation improved WBS of cuts aged for either 7 or 14 d (P = .02 and P = .07, respectively). Sensory panelists rated samples from VITD supplemented steers as more tender than their unsupplemented counterparts. Activation of calpain proteases could be responsible for the observed tenderization due to the supplementation of VITD.     

Probiotic efficiency of Bacillus sp. in Labeo rohita challenged by Aeromonas hydrophila: assessment of stress profile,haemato‐biochemical parameters and immune responses

Fish are always susceptible to a wide variety of deadly pathogens which cause a huge loss in aquaculture industries. In this investigation, we have demonstrated the in vivo probiotic efficiency of Bacillus sp. MVF1 (GenBank Acc. No. KP256503) in Labeo rohita challenged with pathogenic strain of Aeromonas hydrophila (MTCC 1739). To check the probiotic potential of the selected bacterial strain, fish were divided into four groups: control, D1, D2 and D3. A total of 100 days (70 days probiotic feeding + 71th day sampling and 28 days challenged test + 29th day sampling) of feeding trial was conducted. To establish the probiotic potential of Bacillus sp. MVF1, certain haematological parameters (haemoglobin, total erythrocyte and leucocyte count), serum biochemical parameters (total protein, albumin and globulin), immune parameters (serum lysozyme and total IgM levels) and hepatic stress profile (malondialdehyde production, superoxide dismutase and catalase activity) have been measured. Our results demonstrated that red blood cell number, white blood cell number and haemoglobin content were much higher in D2 group fish compared to other groups and control fish. Similarly, total protein contents, albumin concentration, globulin concentration, lysozyme activity and IgM production were also recorded to be highest in D2 group fish. This finding clearly indicated the probiotic potential of Bacillus sp. MVF1 in L. rohita. Furthermore, our results also demonstrated that 1 × 10⁷ CFU g^?1 feed (D2) provides better immunity compared to 1 × 10⁵ (D1) and 1 × 10⁹ (D3). Due to beneficial effects, the bacterium Bacillus sp. MVF1 might be useful in aquaculture industries to reduce the disease susceptibility.     

Effect of plastic mulch on water flow and herbicide transport in soil cultivated with pineapple crop: A modeling study

In Hawaii, pineapple is typically grown in raised beds covered with impervious plastic mulch. Field measurements of a commonly used herbicide (bromacil) mass beneath mulch-covered pineapple beds and inter-bed open areas revealed that open areas contained a mass of bromacil about 3.5 times greater than was originally applied, based on label instructions, to the entire field. The broadcast bromacil ended up in the inter-bed open areas through water runoff from the plastic mulch covering the pineapple beds. The objective of this study was to evaluate the impact of surficial management on water dynamics and bromacil concentration in the soil on a pineapple plantation using the one- (1D) and two-dimensional (2D) flow and transport models. Flow and transport processes were simulated in a 2D vertical cross-section perpendicular to the plant rows. The 1D simulation was limited to the open inter-bed areas. Several simulation scenarios were proposed to evaluate the effect of plastic mulch on bromacil transport in soil. In our simplified approach, the water and solute boundary fluxes for the non-covered areas were increased to simulate the water and solute contribution from the plastic mulch surface. The simulation results were compared with field observations of soil water potentials and resident bromacil concentration profiles. The field and laboratory-measured hydraulic and transport parameters were used for all simulation scenarios. Reasonably good agreement between the model-predicted and observed soil water potentials and bromacil concentration profiles was obtained. Biased 1D and 2D results were predicted when the water runoff from plastic mulch was neglected. The 1D approach to quantify bromacil transport beneath the inter-bed open areas seemed to be sufficient in case the water runoff from the mulch was taken into account.     

Identification of gut‐associated amylase,cellulase and protease‐producing bacteria in three species of Indian major carps

Isolation and enumeration of amylase, cellulase and protease‐producing autochthonous bacteria in the proximal intestine (PI) and distal intestine (DI) of three species of Indian major carps, catla (Catla catla), mrigal (Cirrhinus mrigala) and rohu (Labeo rohita), were investigated using the conventional culture‐based technique. Population levels of amylolytic strains were the highest in the PI of catla and the lowest in the DI of rohu. The highest viable count of cellulase and protease‐producing bacteria was recorded in the DI and PI of mrigal respectively. Among the bacteria isolated, 10 strains (five from PI and five from DI) were selected as potent enzyme producers according to a quantitative enzyme assay. The chosen strains were further identified by 16S rRNA gene sequence analysis. The five strains isolated from catla showed high similarity to Citrobacter sp. clone W2, Enterobacter sp. JA24, Bacillus coagulans strain TR, uncultured bacterial clone Hel3bc04 and Bacillus cereus strain UST2006‐BC004. The four strains isolated from mrigal were most closely related to Bacillus sp. KCd2, uncultured bacterial clone Hel3bd09, B. cereus strain BU040901‐020 and Citrobacter freundii strain YRL11, while the strain isolated from rohu probably belonged to Bacillus sp. GV.     

Effects of antimicrobial peptides on growth,feed utilization,serum biochemical indices and disease resistance of juvenile shrimp,Litopenaeus vannamei

This experiment was conducted to assess the effects of antimicrobial peptides at different levels (Diet 1 (0%), Diet 2 (0.1%), Diet 3 (0.2%), Diet 4 (0.4%), Diet 5 (0.6%) and Diet 6 (1%)), on growth, serum biochemical indices and antioxidant effect, feed utilization and disease resistance in Litopeneaus vannamei. There were four replicates in each group in the experiment (mean weight = 0.21 ± 0.00 g) and also fed with their respective diets for 8 weeks. Growth performance compared with the control group (0%) significantly increased at first and then decreased among treatment groups (p < .05) whereas the survival rate ranged from 78% to 96%. No significant differences were observed in terms of moisture, crude protein and ash content, but there was a significant increase in crude lipid (p < .05). In serum, acid phosphatase, alkaline phosphatase, polyphenol oxidase, triglyceride, glucose and total cholesterol changed as compared with 0%. Total antioxidant capacity, glutathione peroxidase, catalase, superoxide dismutase and malondialdehyde were also different from 0%. Disease resistance was increased in shrimp among treatment groups with 0.4% recording the lowest mortality percentage of 37% after the challenge test. The results from the present study suggested that supplementation of AMP at 0.4% in shrimp diet can improve growth performance, antioxidants activities and innate immune response of Pacific whiteleg shrimp.     

Livelihood Improvements Through Agroforestry: Evidence from Northern Bangladesh

Agroforestry is one of the most sustainable land management systems practiced around the world due to the socioeconomic benefits that it brings to farmers. In Bangladesh, farmers practice agroforestry, applying indigenous knowledge. The present study was designed to identify the present status, management practices and its role in improving the livelihoods of farmers in northern Bangladesh. Data for the study were collected through quantitative and qualitative methods. A total of 29 tree and 38 agricultural crop species were planted by the102 farmers interviewed. Mangifera indica (relative prevalence 49%) is the most predominant species, followed by Eucalyptus camaldulensis (relative prevalence 35.4%). Farmers of northern Bangladesh plant trees in cropland for fruits (90%), fuel wood (87%) and timber production (79%). Fruit trees were planted with wider spacing while forest and fuel wood species were planted with narrower spacing. Farmer’s livelihoods improved enormously by practicing agroforestry as they have more access to food, fodder and fuel wood which is reflected by greater access to livelihood capitals (except social capital). However, farmers have experienced increased incidences of pests and diseases to the annual crops and trees. Agroforestry practices increases species diversity, ensure economic return and sustain farmer’s livelihoods.