Effect of protein level and flushing method on the reproductive performance of rabbits

Fifty‐five New Zealand white × California cross‐bred female rabbits were used to study the effect of protein level and flushing method on the reproductive performance of rabbits. The treatments consisted of three protein diets (18, 20 and 24% crude protein (CP)) and three flushing methods in a 3 × 3 factorial design. The flushing methods consisted of (i) flushing multiparous does and feeding a 16% CP diet during pregnancy; (ii) flushing multiparous does and feeding an 18% CP diet during pregnancy; and (iii) flushing nulliparous does and feeding an 18% CP diet during pregnancy. Flushing rabbits with different levels of protein did not significantly affect gestation length, litter size and mortality of kits. The trend showed an increase in litter weight with the increase in protein level from 18 to 24%. However, kits from does flushed with 24% CP had a higher individual kit weight gain than those on 20 and 18% CP. Gestation length, total litter size at birth, number of kits dead at birth and number of kits dead at 21 days post‐partum were not affected by flushing methods. There was, however, a significant effect of the flushing method on the number of kits alive at birth, and 7, 14 and 21 days post‐partum. Nulliparous does flushed and maintained on 18% CP during pregnancy had a significantly higher number of kits alive at birth, and 7, 14 and 21 days post‐partum. Litter weight was significantly higher for nulliparous does at 7, 14 and 21 days compared with that of multiparous does flushed and placed on a 16 or 18% CP diet during pregnancy. Protein intake during pregnancy had a significant effect on litter birthweight. Nulliparous and multiparous does flushed and placed on an 18% CP diet during pregnancy had a significantly higher litter birthweight than multiparous does flushed and placed on a 16% CP diet during pregnancy. The effect of protein level during pregnancy on the number of kits alive at birth was not significant. There was no interaction between protein level and flushing method on the reproductive performance of rabbits.     

Fabrication and Characterization of Nanocomposite Hydrogel Based on Alginate/Nano-Hydroxyapatite Loaded with Linum usitatissimum Extract as a Bone Tissue Engineering Scaffold

In the current paper, we fabricated, characterized, and applied nanocomposite hydrogel based on alginate (Alg) and nano-hydroxyapatite (nHA) loaded with phenolic purified extracts from the aerial part of Linum usitatissimum (LOH) as the bone tissue engineering scaffold. nHA was synthesized based on the wet chemical technique/precipitation reaction and incorporated into Alg hydrogel as the filler via physical cross-linking. The characterizations (SEM, DLS, and Zeta potential) revealed that the synthesized nHA possess a plate-like shape with nanometric dimensions. The fabricated nanocomposite has a porous architecture with interconnected pores. The average pore size was in the range of 100–200 µm and the porosity range of 80–90%. The LOH release measurement showed that about 90% of the loaded drug was released within 12 h followed by a sustained release over 48 h. The in vitro assessments showed that the nanocomposite possesses significant antioxidant activity promoting bone regeneration. The hemolysis induction measurement showed that the nanocomposites were hemocompatible with negligible hemolysis induction. The cell viability/proliferation confirmed the biocompatibility of the nanocomposites, which induced proliferative effects in a dose-dependent manner. This study revealed the fabricated nanocomposites are bioactive and osteoactive applicable for bone tissue engineering applications.     

Indirect connectivity estimates of amphibian breeding wetlands from spatially explicit occupancy models

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Characterization and expression of NADPH oxidase genes in stimulated splenic neutrophils of tilapia,Oreochromis niloticus by a mix of traditional Chinese medicine and Bacillus species (TCMBS)

Traditional Chinese medicine and Bacillus species (TCMBS) mixture is an immunostimulant with considerable promise as an alternative in improving fish health. However, nothing is known on its effects on the expression of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase genes and production of reactive oxygen species (ROS) in the neutrophils of fish. The full lengths of tilapia phagocytic NADPH oxidase genes gp91^phox, p22^phox, p40^phox, p47^phox, and p67^phox were cloned and their expression profiles after TCMBS stimulus investigated. The cDNAs of tilapia gp91^phox, p22^phox, p40^phox, p47^phox, and p67^phox contained open reading frames of 1698 bp, 561 bp, 1053 bp, 1584 bp, and 1470 bp respectively, encoding 561, 186, 350, 527, and 489 amino acids respectively. Comparison of the deduced amino acid sequences showed that tilapia NADPH oxidase genes shared 58%–91% and 21%–67% identity with those of other teleost and mammals respectively. Besides, tilapia NADPH oxidase genes contain conserved domains and motifs required for ROS generation. Phylogenetic analysis suggested tilapia NADPH oxidase genes were close to those of Fundulus heteroclitus. After 2 weeks of TCMBS application showed significant upregulation in expression of NADPH oxidase genes, antioxidant genes (i.e., superoxide dismutase, catalase, and glutathione‐disulphide reductase), and an increase in the production of ROS compared to the control in splenic neutrophils of tilapia. Collectively, our study provides evidence of the structure of tilapia NADPH oxidase genes and demonstrate that TCMBS application could modulate their activity in neutrophils to improve immunity in tilapia.     

Genomics,genetics and breeding of tropical legumes for better livelihoods of smallholder farmers

Legumes are important components of sustainable agricultural production, food, nutrition and income systems of developing countries. In spite of their importance, legume crop production is challenged by a number of biotic (diseases and pests) and abiotic stresses (heat, frost, drought and salinity), edaphic factors (associated with soil nutrient deficits) and policy issues (where less emphasis is put on legumes compared to priority starchy staples). Significant research and development work have been done in the past decade on important grain legumes through collaborative bilateral and multilateral projects as well as the CGIAR Research Program on Grain Legumes (CRP‐GL). Through these initiatives, genomic resources and genomic tools such as draft genome sequence, resequencing data, large‐scale genomewide markers, dense genetic maps, quantitative trait loci (QTLs) and diagnostic markers have been developed for further use in multiple genetic and breeding applications. Also, these mega‐initiatives facilitated release of a number of new varieties and also dissemination of on‐the‐shelf varieties to the farmers. More efforts are needed to enhance genetic gains by reducing the time required in cultivar development through integration of genomics‐assisted breeding approaches and rapid generation advancement.     

Cowpea (Vigna unguiculata): Genetics,genomics and breeding

Cowpea, Vigna unguiculata (L.), is an important grain legume grown in the tropics where it constitutes a valuable source of protein in the diets of millions of people. Some abiotic and biotic stresses adversely affect its productivity. A review of the genetics, genomics and breeding of cowpea is presented in this article. Cowpea breeding programmes have studied intensively qualitative and quantitative genetics of the crop to better enhance its improvement. A number of initiatives including Tropical Legumes projects have contributed to the development of cowpea genomic resources. Recent progress in the development of consensus genetic map containing 37,372 SNPs mapped to 3,280 bins will strengthen cowpea trait discovery pipeline. Several informative markers associated with quantitative trait loci (QTL) related to desirable attributes of cowpea were generated. Cowpea genetic improvement activities aim at the development of drought tolerant, phosphorus use efficient, bacterial blight and virus resistant lines through exploiting available genetic resources as well as deployment of modern breeding tools that will enhance genetic gain when grown by sub‐Saharan Africa farmers.     

Insect midgut structures and molecules as targets of plant‐derived protease inhibitors and lectins

The midgut of insects is involved in digestion, osmoregulation and immunity. Although several defensive strategies are present in this organ, its organization and function may be disturbed by some insecticidal agents, including bioactive proteins like lectins and protease inhibitors (PIs) from plants. PIs interfere with digestion, leading to poor nutrient absorption and decreasing amino acid bioavailability. Intake of PIs can delay development, cause deformities and reduce fertility. Ingestion of PIs may lead to changes in the set of proteases secreted in the insect gut, but this response is often insufficient and results in aggravation of the malnutrition status. Lectins are proteins that are able to interact with glycoconjugates, including those linked to cell surfaces. Their effects on the midgut include disruption of the peritrophic matrix, brush border and secretory cell layer; induction of apoptosis and oxidative stress; interference with nutrient absorption and transport proteins; and damaging effects on symbionts. In addition, lectins can cross the intestinal barrier and reach the hemolymph. The establishment of resistant insect populations due to selective pressure resulting from massive use of a bioactive protein is an actual possibility, but this can be minimized by the multiple mode‐of‐action of these proteins, mainly the lectins. © 2018 Society of Chemical Industry     

Current research in canine and feline pheromones.

Pheromonotherapy seems to be a new therapeutic approach allowing practitioners to tackle the treatment of behavioral disorders in a natural, specific, and safe way. Although the efficacy of pheromones has been assessed in some specific behavioral problems, it seems that their range of action could cover the wide field of reduction of stress. Therefore, the use of pheromones should not be reduced to treatment of behavioral disorders (potentially associated with psychotropes or a behavioral modification program) but should be included in a strategy of improving the welfare of pets in veterinary structures (during examination and hospitalization) and in breeding networks (separation from the mother and transport). Moreover, further studies may allow the veterinary practitioner to use pheromone analogues in the field of diagnostics to determine the behavioral status of a pet (e.g., anxious or not, dominant or not). Pheromonotherapy is at its beginning, and the use of pheromones in various fields of medicine is heartening.     

Endogenous uric acid and urea metabolism in the chicken

1. Four chickens were used in nine successive experiments using a single injection radioisotope dilution technique to study the kinetics of endogenous uric acid and urea metabolism. 2. Starvation lowered uric acid and urea entry rates, but elevated the extent of degradation of these compounds. 3. Urea turnover time and the extent of urea pool degradation were higher, and urea excretion rate was lower than that of uric acid. 4. In colostomised chickens, the extent of uric acid and urea degradation were lower than in non-colostomised birds. 5. The average uric acid and urea entry rates in chickens fed on a diet containing 200 g protein/kg were 7.32 and 2.6 mumol/h g liver, respectively. 6. It is concluded that the contribution of uric acid and urea to the nitrogen economy of the birds is negligible.