Predicting early pregnancy in Egyptian buffalo cows via measuring uterine and luteal blood flows,and serum and saliva progesterone

Various methods are being employed to detect early pregnancy in domestic animals. This study aimed to predict early pregnancy in buffaloes via measuring the corpus luteum (CL) diameter, the luteal blood flow (LBF) area, the uterine blood flow (UBF) vascularization area, and progesterones in saliva and serum for non-pregnant (NPBs, N = 12) and pregnant (PBs, N = 12) buffaloes. The results revealed that the CL diameter and the luteal color blood flow blue and red (P = 0.0001) areas of the pregnant animals kept increasing from day 1 to day 35 of the gestation period, but it decreased in NPBs on day 21 after reaching a peak from ovulation to day 18. Interestingly, the UBF of the pregnant buffaloes (PBs) kept increasing (P = 0.0001) from ovulation to day 42. The difference of the CL diameter (P = 0.03) and the LBF color blue vascularization area (P = 0.002) between PBs and NPBs became clear from day 14 after ovulation, though the difference of UBF between PBs and NPBs became markedly obvious from day 7 after breeding. Both saliva (P = 0.001) and serum (P = 0.0001) progesterones of PBs continued increasing (P = 0.0001) from day 14 to day 35, but those of NPBs started decreasing (P = 0.0001) from day 14 and reached low values on day 21. Therefore, measuring saliva progesterone in addition to the high LBF (day 14) and UBF (day 7) of the pregnant buffaloes using a Doppler ultrasound could be applicable as noninvasive methods to detect early pregnancy and to improve reproductive management of buffaloes.     

Elimination of tilmicosin in lactating ewes.

Tilmicosin was injected subcutaneously to lactating ewes once at a dose of 10 mg kg-1 b.wt. to determine its plasma, milk, urine and ruminal juice concentrations. Tilmicosin could be detected in all those fluids 30 minutes after injection. Milk and urine concentrations were higher than those of plasma and ruminal juice. The drug was detectable in milk, urine and plasma for 9, 4 and 3 days after injection, respectively. No amount of tilmicosin could be detected in ruminal juice 12 hours following administration. The mean peak concentration of tilmicosin in plasma and milk (Cmax) were 1.29 and 9.5 micrograms ml-1 and were obtained at (Tmax) 5.235 and 15.093 hours, respectively. The drug was slowly eliminated from plasma and milk as indicated by its long half-life (t1/2el) of 15.4 and 26.2 hours, respectively. The mean binding of tilmicosin to plasma and milk proteins in vitro was 16.8% and 26.8%, respectively. The drug was not bound to ruminal juice at any extent. The rate of tilmicosin renal clearance revealed that it was correspondingly increased with higher blood concentrations. While creatinine clearance showed no significant change after tilmicosin administration. The ratio (fractional clearance) between tilmicosin renal clearance to creatinine clearance was less than one indicating that the glomerular filtration is the main pathway of elimination through kidneys. The rate of ruminal gas fermentation in ewes was inhibited after subcutaneous injection of tilmicosin at a dose of 10 mg kg-1 b.wt. The tested samples taken at different time intervals from the rumen of ewes showed a subsequent reduction in the rate of fermentation as compared to control samples. The reduction was correspondingly increased with the increase of tilmicosin concentration in ruminal juice and returned to normal thereafter.     

Survey of viruses infecting open‐field pepper crops in Côte d'Ivoire and diversity of Pepper veinal mottle virus and Cucumber mosaic virus

The prevalence of viruses in pepper crops grown in open fields in the different agro‐ecological zones (AEZs) of Côte d'Ivoire was surveyed. Pepper veinal mottle virus (PVMV; genus Potyvirus) and Cucumber mosaic virus (CMV; genus Cucumovirus) were the most frequent viruses among those surveyed, while tobamoviruses (genus Tobamovirus) were detected at low frequency. PVMV showed a high heterogeneity across AEZs, which may be related to climatic, ecological or agronomical conditions, whereas CMV was more homogeneously distributed. The molecular diversity of CMV and PVMV were analysed from partial genome sequences. Despite the low number of CMV isolates characterized, two molecular groups were revealed, one corresponding to subgroup IA and the other to reassortants between subgroups IA and IB. RNAs 1 and 3 of the reassortants clustered with the IB subgroup of CMV isolates, whereas their RNA 2 clustered with the IA subgroup. Importantly, RNA 1 of CMV isolates of the IB subgroup has been shown to be responsible for adaptation to pepper resistance. The diversity of PVMV in the VPg‐ and coat protein‐coding regions revealed multiple clades. The central part of the VPg showed a high level of amino acid diversity and evidence of positive selection, which may be a signature of adaptation to plant recessive resistance. As a consequence, for efficient deployment of resistant pepper cultivars, it would be desirable to examine the occurrence of virulent isolates in the CMV or PVMV populations in Côte d'Ivoire and to follow their evolution as the resistance becomes more widely deployed.     

High‐level of resistance to spinosad,emamectin benzoate and carbosulfan in populations of Thrips tabaci collected in Israel

BACKGROUND: The onion thrips, Thrips tabaci Lindeman, is a major pest of several crop plants in the genus Allium, such as onions, garlic and chives. In Israel, these crops are grown in open fields and in protected housing. This thrips is usually controlled by the application of chemical insecticides. In recent years, spinosad, emamectin benzoate and carbosulfan have been the major insecticides used for the control of the onion thrips. In the last 4 years, growers of chives and green onion from several regions of Israel have reported a significant decrease in the efficacy of insecticides used to control the onion thrips. RESULTS: The susceptibility of 14 populations of the onion thrips, collected mainly from chives between the years 2007 and 2011, to spinosad, emamectin benzoate and carbosulfan was tested using a laboratory bioassay. The majority of the populations showed significant levels of resistance to at least one of the insecticides. LC₅₀ values calculated for two of the studied populations showed that the resistance factor for spinosad compared with the susceptible population is 21 393, for carbosulfan 54 and for emamectin benzoate 36. Only two populations, collected from organic farms, were susceptible to the insecticides tested. CONCLUSION: This is the first report of a high resistance level to spinosad, the major insecticide used to control the onion thrips. Resistance cases to spinosad were associated with failures to control the pest. Populations resistant to spinosad also had partial or complete resistance to other insecticides used for controlling the onion thrips. Copyright © 2012 Society of Chemical Industry     

Potentiality of Soil Mulch and Sorghum Extract to Reduce the Biotic Stress of Weeds with Enhancing Yield and Nutrient Uptake of Maize Crop

Two field trials were conducted in 2018 and 2019 to develop practical and economically efficient weed control programs in corn. The experiment included six treatments (cowpea, rice straw, sorghum extract, hoeing, foramsulfuron herbicide and weedy check). The treatments were arranged in randomized complete block design with four replicates. Findings showed that reduction in total weed number was evident with application of hoeing, cowpea and rice straw in 2018 and 2019 seasons, in addition to foramsulfuron herbicide and sorghum extract in 2019. Cowpea, hoeing, foramsulfuron herbicide and rice straw recorded higher reduction in dry biomass of grassy weeds in both seasons. Reductions in N, P and K uptake by weeds because of rice straw and cowpea treatments were similar to hoeing treatment in both seasons. The increases in ear grain weight and grain yield ha^?1 due to cowpea and hoeing treatments were similar to rice straw one. In 2019 season, cowpea treatment was the superior practice for improving N, P and K uptake of maize, significantly leveling hoeing for K uptake. The values of gross returns and benefit/cost ratio of cowpea and sorghum extract, respectively, were higher than rice straw application. In conclusion, cowpea as a live mulch achieved acceptable weed control in maize by reducing weeds growth and lowering their ability to deplete the soil nutrients. Also, cowpea treatment improves growth and yield of maize with better utilization of nutrients. Thus, cowpea could be exploited as an eco-friendly method of weed management programs in maize cultivation.

     

The influence of normal and low-rate application of insecticides on populations of the cotton whitefly and melon aphid and associated parasites and predators on cucumber

Studies were conducted in cucumber fields to evaluate the standard and reduced dosage rates of 5 insecticides for control the cotton whiteflyBemisia tabaci (Genn.) and melon aphidAphis gossypii Glov. and effect of insecticide application on associated parasites and predators. Eggs of whitefly appeared to be less susceptibility to all treatments (max. 66% reduction) than larval and pupal stages. Populations of larval and pupal stages of whitefly were significantly reduced in all treated plots. For example (larvae on day 10 after treatment with ethiofencarb, diafenthiuron, and chlorpyrifos methyl 67, 50, and 68% pupae 68, 69, and 75%). Two aphelinid parasitoids,Eretmocerus mundus Mercet andProspaltella lutea Masi, were the most primary important parasitoids of the whitefly pupae in all test plots. Percent parasitism, in most treated plots, were slightly affected as a result of insecticide application. However, all tested insecticides and dosage rates caused severe suppression of emergence of adult parasitoids. Moreover, longevity of adult parasitoids were highly decreased. Populations of the melon aphid were extremely reduced, especially by ethiofencarb and diafenthiuron. Populations of predator species (Chrysopa carnea Steph.,Coccinella undecimpunctata Reiche andSyrphus spp.) were reduced in all treated plots. However, ethiofencarb applied at rates as low as 208.4g a.i./1001 provided equally effective aphid control and conserved numbers of insect predators in the treated plots. Also, the prothiofos and chlorpyrifos methyl applications at rates as low as 166.7 g a.i./1001 kept aphid numbers below than those in control and caused a smaller reduction in the combined populations of insect predators.     

Zur Bestimmung von Zuckerrohrmosaikvirus-Stämmen In Ägypten

Twentyfour samples of naturally mosaic infected sugarcane plants were collected from Giza and Kena Governorates of A. R. E. They were identified as SCMV strain D and its substrains Da and Dc according to their physical properties in diseased samples and symptoms produced on differential hosts. The two substrains are recorded for the time in Egypt as incitants of this disease. Distribution frequency of strains varied with locality. Strain D was distributed more in Giza Governorate than in Kena Governorate while frequency of substrains Dc and Da was of a reverse trend. Dilution end point, thermal inactivation point and longevityin vitro for strain D and its substrains Da and Dc ranged 10^?3–10^?6, 50°C–63°C, and up to 48 h respectively. These properties varied also within each strain.     

Effects of herbicides on consumption,growth and food utilization by cotton leafwormSpodoptera littoralis (Boisd.) larvae

The deterrent effects of nine herbicides on feeding and growth of cotton leafworm,Spodoptera littoralis (Boisd.), larvae were investigated. Fourth-instar larvae were fed on castor-bean leaves treated with recommended field rates of selected herbicides. Nutritional indices were measured regularly throughout the feeding tests until pupation. The food consumed by larvae in most herbicide-treatments was below that of control. Fluazifop [500 active ingredient (AI)], bentazon (250 AI), ametryne (800, 1600 AI), flamprop (130 AI), and isoxynil (187.5 AI) treatments seemed to be the best feeding deterrents. Relative growth rates of larvae fed on leaves treated with bentazon (250 AI), ametryne (1600 AI), gluphosate (1440 AI), glufosinate (800 AI), and bromoxynil (120 AI) were significantly reduced compared to that in control. Likewise, both the efficiency of conversion of ingested food to body substance (ECI) and the efficiency of conversion of digested food to body substance (ECD) were reduced with herbicide treatments below that in control. Approximate digestibility (AD), however, was significantly increased with most herbicide treatments. Moreover, feeding on herbicide-treated leaves resulted in a significant reduction in both pupation and adult emergence compared to that in control.     

Impact of two synthetic pyrethroids and methomyl on management of the cabbage aphid,brevicoryne brassicae (L.) and its associated parasitoid,diaeretiella rapae (M'Intosh)

The effectiveness of two synthetic pyrethroids, cypermethrin and fenvalerate, and of methomyl applied to cabbage plants was tested against the cabbage aphid, Brevicoryne brassicae (L.), and its parasitoid, Diaeretiella rapae (M'Intosh). Dosage rates chosen were equivalent to the manufacturer's maximum and minimum recommendations. Methomyl was considerably more toxic to B. brassicae adults than the two synthetic pyrethroids used. Fenvalerate, at the lowest rate used (71 g ha^?1), showed satisfactory effectiveness in reducing aphid adult population on treated plants by c. 77% below that of the control. All insecticides and rates used significantly reduced the emergence of parasitoid adult D. rapae from mummified aphids compared to the control. Fenvalerate clearly had less impact on emergence than cypermethrin or methomyl at any dosage used, while methomyl has appeared to be the most toxic compound in this respect. Longevity of parasitoid adults was highly affected by insecticide application, particularly those adults emerging from mummified aphids exposed to methomyl or cypermethrin. However, only a slight difference in longevity was seen at the lower rate of 71 g ha^?1 of fenvalerate. At the lowest dosage rates used, methomyl and cypermethrin reduced the F₁-progeny of adult parasitoid females by 70.5% and 58.3%, respectively, of the control, whereas fenvalerate reduced the progeny by only 36.4%.     

Comparative Pharmacokinetics and Bioavailability of Amoxycillin in Chickens after Intravenous,Intramuscular and Oral Administrations

The pharmacokinetics and systemic bioavailability of amoxycillin were investigated in clinically healthy, broiler chickens (n = 10 per group) after single intravenous (i.v.), intramuscular (i.m.), and oral administrations at a dose of 10 mg/kg body weight. The plasma concentrations of amoxycillin were determined using high-performance liquid chromatography (HPLC) and the data were subjected to compartmental and non-compartmental kinetic analyses. Following single i.v. injection, all plasma amoxycillin data were described by a two compartment-open model. The elimination half-lives of amoxycillin were 1.07 h, 1.09 h and 1.13 h after single i.v., i.m. and oral administration, respectively. The total body clearance (Cl(B)) of amoxycillin was 0.80 (L/h)/kg and the volume of distribution calculated as V(d(area)) was 1.12 L/kg, respectively after i.v. administration. Substantial differences in the resultant kinetic data were obtained by comparing the plasma concentration profiles after i.m. injection with that after oral administration. The systemic i.m. bioavailability of amoxycillin was higher (77.21%) than after oral (60.92%) dosing. In vitro, the mean plasma protein binding of amoxycillin amounted to 8.27%. Owing to high clearance of amoxycillin in birds in our study, a plasma level was maintained above 0.25 microg/ml for only 6 h after i.m. and oral routes of administration and consequently frequent dosing may be necessary daily.