Lina S. Jaber

Water Stress in Small Ruminants

Small ruminants are an integral part of farming systems in the marginal arid regions of the world. These areas are characterized by water scarcity and fluctuating precipitation; under the effect of global warming and unpredictable weather, rainfall is becoming even more irregular and water availability more limited. Along with water accessibility, feed and other resources will be markedly affected by climate change. Livestock that are able, in open range, to select high quality forage to maintain a relatively similar basal diet quality from season to season, will have their intake significantly reduced in extremely dry seasons when forage biomass and its quality are low [1]. Hence, selection of adapted animal breeds is very valuable for sustaining animal production under an increasingly challenging environment [2].

Comparison of immunosuppression in dry and lactating Awassi ewes due to water deprivation stress.

In seminomadic farming practice, dry and lactating ewes are exposed to different degrees of water deprivation, leading to stress followed by various disease outbreaks. This study compares quantitatively the immunosuppression toSalmonella Enteritidis (SE) fimbriae (14 and 21 kDa) and other major polypeptides (28.9, 37.7, 42.9, 68.0, 92.6 and 96.8 kDa) in water-deprived dry and lactating ewes. Sixteen dry and lactating multiparous Awassi ewes were divided into four treatment groups (A, A′, B and B′). Ewes in groups A and B were lactating, whereas ewes in groups A′ and B′ were dry. All ewes were administered a killed SE vaccine, subcutaneously in the neck, at the initiation of the experiment. The water availability for ewes in groups B (lactating) and B′ (dry) was ad libitum, while that for ewes in groups A (lactating) and A′ (dry) was once every 4 days. A serum sample was collected from the jugular vein of each ewe at zero time (initiation of the experiment, when SE bacterin was delivered) and at 2, 9, 12, 15 and 18 days post SE vaccination. The percentage reduction in the level of humoral antibody response to polypeptides of ≥21 kDa was more apparent in water-deprived lactating ewes of group A between 9 and 18 days post initiation of thirst. In this period, immunosuppression to polypeptides ≥21 kDa was present in 14 out of 16 observations in group A (water-deprived lactating), with significant immunosuppression in 9 observations in relation to the respective control (p<0.05), while it was present in only 4 out of 16 observations in group A′ (water-deprived dry), with significant immunosuppression in 2 observations (p<0.05). In conclusion, immunosuppression to polypeptides of ≥21 kDa is more significant in lactating water-deprived ewes in the period 9–18 days post initiation of thirst, a result that will influence our future sheep welfare awareness programmes targeting an elimination of the practice of water deprivation in seminomadic sheep farming.

Bioactivity of Origanum syriacum Essential Oil against Candida albicans

ABSTRACT The susceptibility of 14 human isolates of Candida albicans to commercially available vaginal douche materials and to the essential oil of Origanum syriacum was investigated in hamsters. The essential oil of O. syriacum reduced the colonization and adaptability of the C. albicans more than the commercial douche materials (p < 0.05). In addition, a dilution of the Origanum syriacum essential oil in a water solution of dimethyl sulfoxide resulted in complete elimination of C. albicans from hamsters vagina in comparison to untreated controls (p < 0.05).

Bioactivity of origanum syriacum essential oil against candida albicans

ABSTRACT The susceptibility of 14 human isolates of Candida albicans to commercially available vaginal douche materials and to the essential oil of Origanum syriacum was investigated in hamsters. The essential oil of O. syriacum reduced the colonization and adaptability of the C. albicans more than the commercial douche materials (p < 0.05). In addition, a dilution of the Origanum syriacum essential oil in a water solution of dimethyl sulfoxide resulted in complete elimination of C. albicans from hamsters vagina in comparison to untreated controls (p < 0.05).

Oppositional Dynamics of Organic versus Inorganic Contaminants in Oysters Following an Oil Spill

Abstract The objective of this work was to study the dynamics of the level of organic versus inorganic contaminants in oysters following a significant spill of 15,000 t of heavy oil in the Eastern Mediterranean. Twenty oysters were harvested from each of six selected sites at 72 and 305 d subsequent to the oil spill. Results showed a significant decrease over time in the mean of the means of organic contaminants in oysters (total polycyclic aromatic hydrocarbons [TPAH]: 0.354 vs. 0.177 μg g−1 dry weight, P < 0.05; total polychlorinated biphenyl [TPCB]: 0.031 vs. 0.021 μg g−1 dry weight, P < 0.05). Conversely, the mean of means of each of three heavy metals showed a significant increase over time (P < 0.05) (lead [Pb]: 2.791 vs. 3.543 μg g−1 dry weight, P < 0.05; nickel [Ni]: 6.732 vs. 17.682 μg g−1 dry weight; vanadium [V]: 1.874 vs. 15.833 μg g−1 dry weight). The importance of this pattern in oppositional dynamics of organic versus inorganic contaminants in oysters is discussed.

Competitive exclusion against Salmonella Enteritidis in layer chickens by yoghurt microbiota: impact on egg production, protection and yolk-antibody and cholesterol levels

Aims:  This work aims at studying the impact of competitive exclusion of Salmonella serotype Enteritidis infection in layer chickens, by microbiota of fresh and dried‐modified yoghurt, on egg production and weight, protection against infection, and on yolk‐antibody and cholesterol levels.

Optimization of Saanen sperm genes amplification: evaluation of standardized protocols in genetically uncharacterized rural goats reared under a subtropical environment

The purpose of this research is to optimize quantitatively the amplification of specific sperm genes in reference genomically characterized Saanen goat and to evaluate the standardized protocols applicability on sperms of uncharacterized genome of rural goats reared under subtropical environment for inclusion in future selection programs. The optimization of the protocols in Saanen sperms included three production genes (growth hormone (GH) exons 2, 3, and 4, αS1-casein (CSN1S1), and α-lactalbumin) and two health genes (MHC class II DRB and prion (PrP)). The optimization was based on varying the primers concentrations and the inclusion of a PCR cosolvent (Triton X). The impact of the studied variables on statistically significant increase in the yield of amplicons was noticed in four out of five (80%) optimized protocols, namely in those related to GH, CSN1S1, α-lactalbumin, and PrP genes (P < 0.05). There was no significant difference in the yield of amplicons related to MHC class II DRB gene, regardless of the variables used (P > 0.05). The applicability of the optimized protocols of Saanen sperm genes on amplification of uncharacterized rural goat sperms revealed a 100% success in tested individuals for amplification of GH, CSN1S1, α-lactalbumin, and MHC class II DRB genes and a 75% success for the PrP gene. The significant success in applicability of the Saanen quantitatively optimized protocols to other uncharacterized genome of rural goats allows for their inclusion in future selection, targeting the sustainability of this farming system in a subtropical environment and the improvement of the farmers livelihood.

Development of an enzyme-linked immunosorbent assay for quantification of Salmonella enteritidis-specific antibodies in egg yolk

The present study aims at developing an indirect ELISA to quantify yolk antibodies specific to all surface proteins of the invasive Salmonella Enteritidis (SE), which acquired the 1.8, 14.1, and ~ 50 Kb plasmids. An ELISA checkerboard was used in four different experiments to account for the different parameters included in the preliminary ELISA procedure, and consequently to maximize the difference in Optical Density (OD) values between control positive and negative yolk samples. The first experiment aimed at studying the impact of 5% Bovine Serum Albumin (BSA) dissolved in distilled water as a blocking reagent on a 28 µg/well SE antigen-coated plate, while applying the positive and negative control yolk samples to different concentrations of Phosphate-Buffered Saline (PBS).Conjugate application was maintained constant at a dilution of 1:500 in PBS. The second experiment was similar to the first one, but the positive and negative control yolk samples were diluted in PBS-Tween 20, and the conjugate dilution was changed to 1:1500 in PBS-Tween 20. In the third experiment, the conjugate was diluted at 1:1500 in 5% BSA/PBS-Tween 20 diluent or PBS-Tween 20 diluent with no 5% BSA. The objective of the fourth experiment was to study the impact of four different concentrations of SE-coated antigen levels (28µg/well, 56µg/well, 84µg/well, and 112µg/well), while fixing the blocking step with 5% BSA in distilled water, and the conjugate dilution set at 1:1000 in 5% BSA/PBSTween 20, and fixing the control yolk samples dilution at 1% in PBS-Tween 20. This last experimental procedure allowed the highest difference in mean absorbance OD values of the positive control minus the negative control samples, which was equivalent to 0.381. In addition, the final protocol for this ELISA was applied on individual egg yolk samples of two groups of chicken layers: one challenged in the esophagus at 11 days with 5.4 x 1010 CFU/ml/bird of SE, and the second group was not challenged. The mean OD values of the egg yolk of antibodies specific against SE of the two groups were significantly different (0.8578 versus 0.5250; p<0.05), which indicates the possible application of the developed ELISA for screening SE infection by examining egg yolks produced by commercial layers.

Livestock and food security in the Arab region: policy framework

Livestock keeping constitutes a traditional and important economic activity in the Arab region. This paper aims to assess the role of the Arab livestock sector in food and nutritional security in terms of demand, supply, national policies and trade in the light of major environmental constraints, with data illustrations from Morocco (Mediterranean country) and Saudi Arabia (oil-rich country). Demand for livestock products is increasing in the Arab region driven by the growing population with different degrees of increased urbanization and wealth. On the supply side, local livestock production is largely based on rainfed mixed and pastoral livestock systems making it vulnerable to the effects of climate change and water scarcity. Intensive systems, where present, are mostly dependent on feed imports with an important water footprint. Livestock production is further conditioned by a history of arbitrary national policies that had a particularly negative effect on small producers and contributed to the degradation of national resources. Arab countries rely on trade from the world market to fill their gap in animal feed and livestock products with varying trading power based on wealth and the availability of free trade agreements. Following analysis of the sector, the paper concludes with the proposition of a pro-poor policy framework for the development of a sustainable Arab livestock sector.