Mycoplasmas from donkeys and horses in the Sudan

Seventeen isolates (4.27%) were recovered from 398 samples. Twelve isolates (4%) were obtained from 300 donkey nasal swabs, three (4.3%) and two (6.89%) isolates were recovered from 69 horse nasal swabs and 29 mare uterine washings, respectively. Nine isolates were lost during storage at -20 degrees C and the remaining eight were identified as mycoplasmas and their biological, biochemical and serological reactions were investigated. The isolates could be divided into two groups on the basis of glucose fermentation and arginine hydrolysis. The first group neither fermented glucose nor hydrolysed arginine. Organisms in the second group hydrolysed arginine only.     

Verte and Romaine lettuce varieties (Lactuca sativa) show differential responses to high NaCl concentrations

In this study, we report on the relationship between individual antioxidant carotenoids, phenolic fractions, and flavonoids and attenuating NaCl toxicity in two contrasting varieties of lettuce (Lactuca sativa L., var. Verte and Romaine), as a means of developing more precise targets for lettuce breeding. In seedling leaves, carotenoid levels increased under NaCl stress in Verte, but remained unchanged in Romaine. Chlorogenic acid (CGA), a soluble polyphenol abundantly present in leaves, was the only phenolic acid that accumulated significantly in both varieties and was predominant under salinity. Remarkably, CGA was more prominent in Verte than Romaine at moderate salinity levels (100 mM). Foliar flavonoid levels were also differentially increased in both seedling types grown under 100 mM NaCl, but dropped significantly in both varieties under 200 mM NaCl. Germination, which was overall more salt‐resistant in Romaine, was significantly increased under salt stress by application of low dosage (10^–6 to10^–5 M) of CGA to Verte, but not to Romaine. These results suggest that CGA is involved in modulating NaCl‐induced oxidative‐stress responses during seed germination in Verte.     

Egg storage and breeder age impact on egg quality and embryo development

Prolonged hatching egg storage (>7 days) influences internal egg quality and embryo survival during both storage and subsequent incubation. Moreover, effects of storage of hatching eggs interact with the breeder age. The aim of this review was to investigate how this interaction between storage duration and breeder age affects egg, embryo, hatchling and chicken characteristics. Prolonged storage resulted in a reduction in egg quality in both young and old breeders. This reduction was more pronounced in young flocks than in older flocks. For example, albumen pH increased more after 8 days of storage in younger flocks than in older flocks. Additionally, the embryonic morphological stage appears to increase as well with storage duration, but this increase is again more pronounced in younger flocks than in older flocks. Short storage (<7 days) seems to increase hatchability of eggs from young breeders, probably as a result of albumen liquefaction with consequently better oxygen availability for the embryo. However, long storage (>7 days) resulted in a decline in hatchability, which was stronger in older breeders than in younger breeders. Prolonged storage duration resulted in lower chicken quality in both young and old breeders, but interaction between storage duration and breeder age on multiple chicken quality parameters is not clear. Based on this review, it can be concluded that (a) Short storage can improve hatchability of eggs from young breeders, but not from older breeders. (b) Negative impact of long storage appears to be lower with young breeders than with old breeders. (c) Adapted storage conditions related to the age of breeders might be an option to reduce negative effects of prolonged storage on hatching egg quality and chicken quality.     

Phenotypic diversity of durum wheat (<Emphasis Type="Italic">Triticum durum</Emphasis> Desf.) from Jordan

Durum wheat landrace genotypes are disappearing from the main wheat areas in Jordan, because of spreading of new uniform cultivars and the serious reduction in wheat cultivation. This study was conducted to evaluate genetic diversity in durum wheat landraces from Jordan and to identify desirable agronomic traits. Landraces were collected from two target areas: Ajloun and Karak. The collected material was grown under rainfed conditions using an augmented design with five blocks and four repeated check cultivars. Data were collected for 14 morphological and agronomic traits. Phenotypic diversity index (H′) was estimated, and the relationships among accessions were measured using cluster analysis and dendrogram similarity matrix. The results revealed the presence of a wide range of variability among landraces., which possess high levels of variability for biological yield, fertile tillers, number of seeds per spike, seed weight per spike and weight of 1000 seeds. These landraces must be considered as a reservoir of genes that plant breeders need in their wheat improvement programs and should be conserved both ex situ and in situ.     

INFLUENCE OF DIFFERENT SEED PRIMING METHODS FOR IMPROVING SALT STRESS TOLERANCE IN LETTUCE PLANTS

Seeds of lettuce, variety Romaine were subjected to different priming treatments such as water, potassium nitrate (KNO₃) and gibberellic acid (GA₃). Seedlings obtained from primed (Pr) and nonprimed (NP) seeds were grown in a hydroponic culture system supplemented with 0, 100 or 200 mM sodium chloride (NaCl). The different physiological and biochemical responses were studied 15 days after treatment. Under NaCl, the dry weight was higher in plants derived from hydro-primed (HP) seeds when compared to NP, osmoprimed (KNO₃P), and hormonal primed (GA₃P) ones. Under control and 100 mM NaCl treatment, malondialdehyde (MDA) content and EL did not show any correlation with activities of gaiacol peroxidase (GPX) and catalase (CAT), but did with the increase in reduced ascorbate (AsA) and total ascorbate contents. The results indicated that plants derived from HP seeds exhibited higher adaptive potential under salinity stress. Our findings suggest that a hydropriming technique can be used as a simple commercial approach to alleviate the effects of NaCl induced stress in lettuce plants.     

Preliminary observations on the natural variation in the endogenous rhythm of the desert Isopod Hemilepistus reaumurii

The desert woodlouse Hemilepistus reaumurii lives in monogamous pairs, together with their offspring, in self-dug burrows. Every burrow contains only one family. This animal is active on the surface from the beginning of spring to autumn. It remains in the burrow during the hottest part of the day, to avoid the heat, but is active at the surface during morning and evening. During the winter, low temperature prevents its above ground activity. Freshly collected animals, from the north of Kairouan (Tunisia) were transferred to a controlled environment cabinet in the laboratory and their locomotor activity monitored as individuals or in male/female pairs, in annular chambers equipped with an infrared activity recording system. For the first 7 days of recording, the animals were kept in a light–dark cycle in phase with the natural diel cycle. For the second 7 days, animals were maintained in constant darkness. The temperature was held constant at 18±1 °C. Analysis of preliminary data indicates that both individuals and pairs exhibit an endogenous rhythm of locomotor activity with a circadian periodicity. Activity was mostly confined to the hours of the photophase (1–7 days) or to those of subjective day (8–14 days). The activity pattern showed two main peaks, around dusk and dawn, respectively. This bimodal circadian rhythm persisted for as long as the experiments were run, and was clearer in individual recording than in pair recording. The characteristics and biological significance of the rhythm are discussed.     

Effects of dietary synbiotic on growth,survival, lactobacillus bacterial count,blood indices and immunity of beluga (Huso huso Linnaeus, 1754) juvenile

This study aimed to determine the effect of synbiotic (Biomin IMBO) as feed additive on beluga (Huso huso) juvenile with an average body weight of 26.45 ± 0.19 g. Experimental diets at which supplemented with 1.0, 2.0 and 4.0 g synbiotic per kg of feed were fed to beluga juvenile, whereas the control group was fed with no synbiotic. After the feeding trial for 8 weeks, growth performance, survival, lactobacillus bacterial count, blood indices and immunity were tested. Even though, some growth performance and feed utilization parameters including WG, SGR and FCR were improved in group fed with 2.0 g kg^?1 synbiotic; however, there were no significant differences (P > 0.05) in growth and feeding parameters between juveniles fed control and synbiotic supplementation diets. In terms of intestinal microbiota, there were no significant differences in total and lactic acid bacteria among treatments (P > 0.05). In addition, there were no significant differences of RBC counts, haematocrit, monocyte, lymphocyte, neutrophil, serum glucose and serum total protein levels between the treatment groups (P > 0.05), but group 2 and 4 g kg^?1 synbiotic showed a significant difference (P < 0.05) in WBC counts and haemoglobin, respectively. Furthermore, alternative complement activity (ACH50) and serum total immunoglobulin (Ig) were significantly increased in 2.0 g kg^?1 synbiotic fed fish (P < 0.05); however, it did not change the lysozyme activity, significantly (P > 0.05). These results indicate that synbiotic improves immunity of beluga sturgeon without detrimentally impacting the growth performance, modulates intestinal microbiota and basic haematological parameters assessed. Thus, we suggest that 2.0 g kg^?1 level of synbiotic may be used as an immunity promoter for beluga sturgeon juvenile.     

Trypsin from the viscera of Bogue (<Emphasis Type="Italic">Boops boops</Emphasis>): isolation and characterisation

Trypsin from the viscera of Bogue (Boops boops) was purified to homogeneity by precipitation with ammonium sulphate, Sephadex G-100 gel filtration and Mono Q-Sepharose anion exchange chromatography, with an 8.5-fold increase in specific activity and 36% recovery. The molecular weight of the purified enzyme was estimated to be 23 kDa by SDS–PAGE and size exclusion chromatography. The purified trypsin appeared as a single band on native-PAGE and zymography staining. The purified enzyme showed esterase-specific activity on N-α-benzoyl-l-arginine ethyl ester (BAEE) and amidase activity on N-α-benzoyl-dl-arginine-p-nitroanilide (BAPNA). The optimum pH and temperature for the enzyme activity, after 10 min incubation, were pH 9.0 and 55°C, respectively, using BAPNA as a substrate. The trypsin kinetic constants K _m and k _cat on BAPNA were 0.13 mM and 1.56 s⁻¹, respectively, while the catalytic efficiency k _cat /K _m was 12 s⁻¹ mM⁻¹. Biochemical characterisation of B. boops trypsin showed that this enzyme can be used as a possible biotechnological tool in the fish processing and food industries.