Effects of imidacloprid-contaminated feed exposure on spermatogenic cells and Leydig cells in testes of adult male rabbits (Oryctolagus cuniculus)

This research was undertaken to assess the results of repeated exposure to the insecticide; imidacloprid (IMI)-contaminated feed on testicular tissue, spermatogenic cell population, Leydig cell number, and sperm morphology in adult male rabbits (n = 24). The treatment groups received IMI (Bildor® 100 mg/L water spray on green grass)-contaminated green grass without wash (n = 8, not-washed-feed rabbit group) and after wash (n = 8, washed-feed rabbit group) once daily for two weeks on an alternate day basis. The rest of the rabbits, as control, received a normal pesticide-free standard feed. During the exposure time, there was no evident toxic symptom found on regular monitoring of IMI-treated rabbits. Histopathologically, the thickness of tunica albuginea of testes reduced significantly with loosely arranged connective tissues in IMI-treated rabbits. Within the testes, the bizarre-shaped seminiferous tubules were seen with increased lumen diameter in IMI-treated rabbits. The spermatogenic cells were disorganized and detached from the basement membrane in seminiferous tubules of IMI-exposed testes of rabbits. The spermatogenic cell population decreased significantly (P < 0.05) in IMI-treated rabbits compared to control rabbits. Leydig cell number decreased significantly (P < 0.05) in IMI-treated rabbits. A high percentage of morphologically abnormal spermatozoa was seen in IMI-treated rabbits. The degree of the histopathological changes was more prominent in the testes of IMI-exposed not-washed-feed rabbits. The results showed that insecticide-IMI has toxicological effects on testicular tissues, mainly spermatogenic and Leydig cell population of adult rabbits which may cause infertility.A short running title: Effect of imidacloprid on testicular tissue of rabbits.     

Feeding graded levels of dried Sea buckthorn (Hippophaes rhamnoides) berries to broiler chickens

The aim of this study was to assess the effects of graded levels (0, 3, 6, 9 and 12 g/kg) of dry Sea buckthorn (SB) berries on growth performance, gastrointestinal tract (GIT) development, jejunal histomorphology, bird antioxidant status and caecal short-chain fatty acid concentration when fed to female Ross 308 broiler chickens. In addition, expression of cytokine biomarker genes in the jejunum was evaluated. The five experimental diets were fed from 7 to 21 days age to 8 pens (two birds in each) following randomisation. Feeding SB did not influence bird growth performance (p > .05). There was a linear decrease in butyric, acetic and valeric acid concentrations in caecal digesta (p < .05) and a decrease (p < .05) in crypt depth. The expression of IFNG and CD40LG responded quadratically (p < .05), peaking at 6–9 g/kg dietary inclusion of SB, respectively. Other studied variables were not affected by dietary SB inclusion (p > .05). Feeding dry SB berries up to 12 g/kg of diet did not improve the zootechnical variables of healthy commercial-strain broilers in this study.     

Investigation Into the Humaneness of Slaughter Methods for Guinea Pigs (Cavia porcelus) in the Andean Region

Guinea pigs (Cavia porcelus) are an important source of nonhuman animal protein in the Andean region of South America. Specific guidelines regarding the welfare of guinea pigs before and during slaughter have yet to be developed. This study critically assessed the humaneness of 4 different stunning/slaughter methods for guinea pigs: cervical neck dislocation (n = 60), electrical head-only stunning (n = 83), carbon dioxide (CO₂) stunning (n = 21), and penetrating captive bolt (n = 10). Following cervical neck dislocation, 97% of guinea pigs had at least 1 behavioral or cranial/spinal response. Six percent of guinea pigs were classified as mis-stunned after electrical stunning, and 1% were classified as mis-stunned after captive bolt. Increased respiratory effort was observed during CO₂ stunning. Apart from this finding, there were no other obvious behavioral responses that could be associated with suffering. Of the methods assessed, captive bolt was deemed the most humane, effective, and practical method of stunning guinea pigs. Cervical neck dislocation should not be recommended as a slaughter method for guinea pigs.     

Effect of age,size and digestive tract development on weaning effectiveness in crucian carp,Carassius carassius (Linnaeus, 1758)

The study aim was to determine the optimum age, wet body weight (WBW) and total length (TL) of the crucian carp, Carassius carassius (L.), to ensure the effectiveness of weaning directly without a gradual transfer from live food to a compound feed. Moreover, the state of development of the digestive tract was analyzed histologically based on the height of enterocytes. Experimental rearing was conducted between days 5 and 45 post hatch (DPH). Initial WBW of fish was 2.2 ± 0.6 (n = 30) mg and TL 6.1 ± 0.1 (n = 30) mm. Rearing was carried out at 27 ± 0.5°C, with fish divided into six groups: one control (C) fed with Artemia sp. nauplii, and five groups initially fed with Artemia sp. but later replaced by a compound feed. Weaning with the compound diet started at 15, 20, 25, 30 and 35 DPH in groups labeled F15, F20, F25, F30, F35, respectively. Larvae were fed three times per day (08.00 h, 13.00 h, 18.00 h) in equal portions (4% of larvae biomass per day, converted to the dry matter of the feed). Daily biomass growth was adopted as 15%. Each group was triplicated (n = 50 individuals per replicate). Highest values of TL 42.1 ± 0.7 (n = 30) mm and WBW 905.3 ± 50.3 (n = 30) mg were recorded in the control group at 45 DPH; lowest survival rate of 45 DPH was in group F15 (90.7 ± 1.2%, n = 30). The highest value of the enterocyte epithelial length was observed in individuals within groups F30, 34.8 ± 1.2 μm (n = 30) and F35, 35.4 ± 3.6 μm (n = 30), respectively, 30 and 35 DPH; highest percentage of deformations on the final day of the experiment was in group F15 (100 ± 0.0%, n = 30). The results indicate that an effective direct transfer from live food to prepared diets (with no gradual transfer) cannot be performed with crucian carp larvae before 30 DPH at 27°C, when the fish have reached TL = 31.1 ± 0.4 mm (n = 30) and WBW = 436.9 ± 13.7 mg (n = 30).     

Effects of exposure to imidacloprid contaminated feed on the visceral organs of adult male rabbits (Oryctolagus cuniculus)

The best-known and often used systemic, broad-spectrum neonicotinoid pesticide is imidacloprid (IMI). This study was carried out on adult male rabbits (n = 12) to assess the residual effects of exposure to IMI-contaminated diet on the liver, lung, heart, and kidney. Pesticide-exposed rabbits (n = 6) received IMI contaminated green grass (Bildor® 0.5 ml (100 mg)/L water) every alternative day once daily for up to 15 days. The remaining rabbits were fed a standard diet free of pesticides as a control. During routine monitoring of the rabbits throughout the experiment, there were no apparent toxic symptoms identified. On days 16, after deep anesthesia blood and visceral organs were collected. The levels of hepatic serum aspartate transaminase and alanine transaminase were considerably elevated in IMI-exposed rabbits (p ≤ 0.05). Thin layer chromatography revealed that the residue of IMI was at the detectable level in the liver and stomach. Histopathologically, the liver revealed coagulation necrosis with granulomatous inflammation and congestion in portal areas with dilated and congested central veins. The lungs showed congestion of blood vessels and granulomatous inflammation around the terminal bronchiole. Accumulations of inflammatory cells were observed in the cortico-medullary junction in the kidney. The heart showed necrosis and infiltration of mononuclear cells within the cardiac muscles. The findings of the current study emphasize that IMI-contaminated feed exposure causes toxicity into the cellular level of different visceral organs of adult male rabbits and it may also cause the similar toxic effects of the other mammals specially the occupationally exposed persons.     

Antibiotic-Resistant Organisms Cultured from Atlantic Bottlenose Dolphins (Tursiops truncatus) Inhabiting Estuarine Waters of Charleston, SC and Indian River Lagoon, FL

Bottlenose dolphins (Tursiops truncatus) from estuarine waters of Indian River Lagoon, FL (IRL) and Charleston, SC (CHS) were cultured to screen for microorganism colonization and to assess antibiotic sensitivity. Swabs (n = 909) were collected from the blowhole, gastric fluid, and feces of 171 individual dolphins The most frequently cultured organisms were Plesiomonas shigelloides (n = 161), Aeromonas hydrophila (n = 144), Escherichia coli (n = 85), and Pseudomonas fluorescens (n = 82). In descending frequency, organisms demonstrated resistance to erythromycin, ampicillin, and cephalothin. Human and animal pathogens resistant to antibiotics used in human and veterinary medicine were cultured. Escherichia coli (E. coli) more often was resistant in IRL dolphins. Three cases of methicillin-resistant Staphylococcus aureus (MRSA) were found at CHS. Emergence of antibiotic resistance is not confined to humans. Bottlenose dolphins may serve as sentinels for transfer of resistance from humans and animals or indicate that antibiotics are reaching the marine environment and causing resistance to emerge through selective pressure and genetic adaptation.     

Evolutionary trends in Hoplerythrinus unitaeniatus (Agassiz 1829) (Characiformes, Erythrinidae)

Hoplerythrinus unitaeniatus is a species of economic importance, widely distributed in the Brazilian territory. Many studies have reported the karyotypic variation that occurs in the species, which forms two groups according to the diploid number, one with 2n = 52 and the other with 2n = 48. In this work, three populations of H. unitaeniatus from different hydrographic basins were cytogenetically analyzed. The diploid number found was 2n = 48 for all populations, however, differences in karyotypic formula and fundamental number and heterochromatin distribution were also observed. Ag-NORs were multiple, GC-rich and when applied FISH with 18S rDNA bright signals in six chromosomes were observed. Data from this study confirm the occurrence of interpopulation variability in H. unitaeniatus. The basal number and the possible divergence among the different cytotypes analyzed for this species to date, as well as the forward the proposal of biogeographic and tectonic history for the continental margin are discussed.     

Seasonal variation in gut morphology in wild rabbits (Oryctolagus cuniculus)

It is shown experimentally that diet composition affected the sizes of several digestive organs in juvenile rabbits collected from the wild. Stomach weight, small intestine volume and colon length were larger in rabbits reared on diets higher in fibre. Small intestine weight, however, was lower.
Analysis of natural variation in wild adult rabbits showed that all digestive organs (except for the appendix) were larger in rabbits living on chalk soils than in those living on sand or clay. Seasonal variation was more marked in males than in females, probably because of the sexes' different breeding requirements. Thus most male digestive organs were smaller between December and June than at other times of year. Female digestive organs did not show this pattern, and were largest in May/June, when the demands of pregnancy and lactation are highest. However, food quality may have been important too. Food quality is probably highest in April, and most digestive organs were then smallest (both sexes). The dry weights of stomach and small intestine did not fit these patterns. Stomach weight increased with the presence of the nematode parasite Graphidium strigosum and small intestine and caecal volumes with the presence of cestodes. Numbers of nematodes (Trichostrongylus retortaeformis and Passalurus ambiguus) in the caecum or colon, however, had no effects on organ sizes.
Data are presented on variation in intensity and prevalence of these helminth parasites with season and soil type.     

Length–weight relationships of Dermogenys pusilla Kuhl & van Hasselt, 1823 (Zenarchopteridae) and Labeo bata (Hamilton, 1822) (Cyprinidae) from the Ganges River (NW Bangladesh)

Length‐weight relationships (LWRs) were determined for Dermogenys pusilla (n = 75) and Labeo bata (n = 304) from the Ganges River, northwestern Bangladesh, collected between July 2013 and June 2014, using traditional fishing gear (e.g. cast net, square lift net and gill net). Total length (TL) was measured to 0.1 cm and whole body weight (BW) was taken to the nearest 0.1 g for each individual. The TL varied from 6.60 to 16.10 cm for D. pusilla and 7.90–25.20 cm for L. bata. The BW ranged from 1.20 to 10.90 g for D. pusilla and 4.70–167.30 g for L. bata. All LWRs were highly significant (P < 0.001), with all r² values ≥0.976. Moreover, the present study provides a new record of the maximum length (16.10 cm TL) for the D. pusilla female. The present study can assist in the management of these two endangered species in the Ganges River ecosystem.     

Genome‐wide SNP analysis unveils genetic structure and phylogeographic history of snow sheep (Ovis nivicola) populations inhabiting the Verkhoyansk Mountains and Momsky Ridge (northeastern Siberia)

Insights into the genetic characteristics of a species provide important information for wildlife conservation programs. Here, we used the OvineSNP50 BeadChip developed for domestic sheep to examine population structure and evaluate genetic diversity of snow sheep (Ovis nivicola) inhabiting Verkhoyansk Range and Momsky Ridge. A total of 1,121 polymorphic SNPs were used to test 80 specimens representing five populations, including four populations of the Verkhoyansk Mountain chain: Kharaulakh Ridge–Tiksi Bay (TIK, n = 22), Orulgan Ridge (ORU, n = 22), the central part of Verkhoyansk Range (VER, n = 15), Suntar‐Khayata Ridge (SKH, n = 13), and Momsky Ridge (MOM, n = 8). We showed that the studied populations were genetically structured according to a geographic pattern. Pairwise F_ST values ranged from 0.044 to 0.205. Admixture analysis identified K = 2 as the most likely number of ancestral populations. A Neighbor‐Net tree showed that TIK was an isolated group related to the main network through ORU. TreeMix analysis revealed that TIK and MOM originated from two different ancestral populations and detected gene flow from MOM to ORU. This was supported by the f3 statistic, which showed that ORU is an admixed population with TIK and MOM/SKH heritage. Genetic diversity in the studied groups was increasing southward. Minimum values of observed (Ho) and expected (He) heterozygosity and allelic richness (Ar) were observed in the most northern population—TIK, and maximum values were observed in the most southern population—SKH. Thus, our results revealed clear genetic structure in the studied populations of snow sheep and showed that TIK has a different origin from MOM, SKH, and VER even though they are conventionally considered a single subspecies known as Yakut snow sheep (Ovis nivicola lydekkeri). Most likely, TIK was an isolated group during the Late Pleistocene glaciations of Verkhoyansk Range.     

Molecular Characterization of Pneumococcal Isolates from Pets and Laboratory Animals

Background

Between 1986 and 2008 Streptococcus pneumoniae was isolated from 41 pets/zoo animals (guinea pigs (n = 17), cats (n = 12), horses (n = 4), dogs (n = 3), dolphins (n = 2), rat (n = 2), gorilla (n = 1)) treated in medical veterinary laboratories and zoos, and 44 laboratory animals (mastomys (multimammate mice; n = 32), mice (n = 6), rats (n = 4), guinea pigs (n = 2)) during routine health monitoring in an animal facility. S. pneumoniae was isolated from nose, lung and respiratory tract, eye, ear and other sites.

Methodology/Principal Findings

Carriage of the same isolate of S. pneumoniae over a period of up to 22 weeks was shown for four mastomys. Forty-one animals showed disease symptoms. Pneumococcal isolates were characterized by optochin sensitivity, bile solubility, DNA hybridization, pneumolysin PCR, serotyping and multilocus sequence typing. Eighteen of the 32 mastomys isolates (56%) were optochin resistant, all other isolates were optochin susceptible. All mastomys isolates were serotype 14, all guinea pig isolates serotype 19F, all horse isolates serotype 3. Rats had serotypes 14 or 19A, mice 33A or 33F. Dolphins had serotype 23F, the gorilla serotype 14. Cats and dogs had many different serotypes. Four isolates were resistant to macrolides, three isolates also to clindamycin and tetracyclin. Mastomys isolates were sequence type (ST) 15 (serotype 14), an ST/serotype combination commonly found in human isolates. Cats, dogs, pet rats, gorilla and dolphins showed various human ST/serotype combinations. Lab rats and lab mice showed single locus variants (SLV) of human STs, in human ST/serotype combinations. All guinea pig isolates showed the same completely new combination of known alleles. The horse isolates showed an unknown allele combination and three new alleles.

Conclusions/Significance

The isolates found in mastomys, mice, rats, cats, dogs, gorilla and dolphins are most likely identical to human pneumococcal isolates. Isolates from guinea pigs and horses appear to be specialized clones for these animals. Our data redraw attention to the fact that pneumococci are not strictly human pathogens. Pet animals that live in close contact to humans, especially children, can be infected by human isolates and also carriage of even resistant isolates is a realistic possibility.     

Time course determination of the effects of rapid and gradual cooling after acute hyperthermia on body temperature and intestinal integrity in pigs

Rapid cooling after acute hyperthermia may cause a sustained increase in body temperature and exacerbate intestinal damage in pigs. Therefore, the study objective was to evaluate the temporal effects of rapid and gradual cooling on body temperature response and intestinal integrity after acute hyperthermia in pigs. In three repetitions, 54 pigs [83.3 ± 6.7 kg initial body weight (BW)], balanced by sex were exposed to thermoneutral conditions for 6 h (TN; n = 6 pigs/repetition; 21.1 ± 2.0°C), or heat stress conditions (HS; 39.3 ± 1.6°C) for 3 h, followed by a 3 h recovery period of gradual cooling [HSGC; n = 6 pigs/repetition; gradual decrease from HS to TN conditions] or rapid cooling [HSRC; n = 6 pigs/repetition; rapid TN exposure and cold water (4.0°C) dousing every 30 min for 1.5 h]. Feed was withheld throughout the entire 6 h period, but water was provided ad libitum. Gastrointestinal (T_GI) and rectal (T_R) temperatures were recorded every 15 min during the HS and recovery periods. Six pigs per repetition (n = 2/treatment) were euthanized and jejunal and ileal samples were collected for histology immediately after (d 0), 2 d after, and 4 d after the recovery period. Data were analyzed using PROC MIXED in SAS 9.4. Overall, rapid cooling reduced T_R and T_GI (P < 0.01; 0.95°C and 0.74°C, respectively) compared to gradual cooling. Jejunal villus height was reduced overall (P = 0.02; 14.01%) in HSGC compared to HSRC and TN pigs. Jejunal villus height-to-crypt depth ratio was reduced overall (P = 0.05; 16.76%) in HSGC compared to TN pigs. Ileal villus height was reduced overall (P < 0.01; 16.95%) in HSGC compared to HSRC and TN pigs. No other intestinal morphology differences were detected. In summary, HSRC did not cause a sustained increase in body temperature and did not negatively impact biomarkers of intestinal integrity in pigs.     

Chromosomal distribution of interstitial telomeric sequences as signs of evolution through chromosome fusion in six species of the giant water bugs (Hemiptera,Belostoma)

Tandem arrays of TTAGG repeats show a highly conserved location at the telomeres across the phylogenetic tree of arthropods. In giant water bugs Belostoma, the chromosome number changed during speciation by fragmentation of the single ancestral X chromosome, resulting in a multiple sex chromosome system. Several autosome–autosome fusions and a fusion between the sex chromosome pair and an autosome pair resulted in the reduced number in several species. We mapped the distribution of telomeric sequences and interstitial telomeric sequences (ITSs) in Belostoma candidulum (2n = 12 + XY/XX; male/female), B. dentatum (2n = 26 + X₁X₂Y/X₁X₁X₂X₂), B. elegans (2n = 26 + X₁X₂Y/X₁X₁X₂X₂), B. elongatum (2n = 26 + X₁X₂Y/X₁X₁X₂X₂), B. micantulum (2n = 14 + XY/XX), and B. oxyurum (2n = 6 + XY/XX) by FISH with the (TTAGG)_n probes. Hybridization signals confirmed the presence of TTAGG repeats in the telomeres of all species examined. The three species with reduced chromosome numbers showed additional hybridization signals in interstitial positions, indicating the occurrence of ITS. From the comparison of all species here analyzed, we observed inverse relationships between chromosome number and chromosome size, and between presence/absence of ITS and chromosome number. The ITS distribution between these closely related species supports the hypothesis that several telomere–telomere fusions of the chromosomes from an ancestral diploid chromosome number 2n = 26 + XY/XX played a major role in the karyotype evolution of Belostoma. Consequently, our study provide valuable features that can be used to understand the karyotype evolution, may contribute to a better understanding of taxonomic relationships, and also elucidate the high plasticity of nuclear genomes at the chromosomal level during the speciation processes.     

Allozyme variations in Anatolian populations and cytotypes of the blind mole rats (Nannospalax)

Enzymatic proteins encoded by 28 putative loci in 326 samples of 12 mol rat cytotypes collected from 97 localities in Anatolia were investigated by standard horizontal starch-gel electrophoresis. A total of 61 alleles were determined for 28 isozyme loci and 23 of the 28 were polymorphic. Eight of the 23 polymorphic loci were agreeable to the Hardy–Weinberg equilibrium. It was determined that deviations from the Hardy–Weinberg equilibrium in the examined populations were due to a heterozygote deficiency. It was revealed by allozyme analyses that mole rat populations in Anatolia have formed 4 cytotypes groups, represented by 4 species (Nannospalax xanthodon, Nannospalax ehrenbergi, N. cilicicus, and N. nehringi). Cytotypes in western Anatolia (2n = 36, 2n = 38, 2n = 40, 2n = 52) showed private alleles in different enzyme systems; therefore, these cytotypes were genetically different, both from each other and other cytotypes. Although cytotypes in central Anatolia (2n = 52S, 2n = 56, 2n = 58, and 2n = 60) contained a different diploid chromosome number, they showed identical patterns in terms of their allele content in the 28 enzymatic loci.     

Response of splenic melanomacrophage centers of Oreochromis niloticus (Linnaeus, 1758) to inflammatory stimuli by BCG and foreign bodies

The study objective was to make histological, histochemical and morphometric evaluations on the splenic Melanomacrophage centers (MMCs) of tilapias, Oreochromis niloticus (Linnaeus, 1758), that were subjected to chronic inflammation stimuli by implantation (IMP) of a glass coverslip in the subcutaneous tissue and through inoculation of the bacillus Calmette‐Guerin (BCG). Randomly distributed in four groups were 150 tilapias: IMP (n = 45); IMP+BCG (n = 45); BCG (n = 45); and control (n = 15). Nine fish per treatment and three control fish were sampled on days 3, 7, 14, 21 and 33. The results demonstrated that increased numbers and areas of these structures were related to the type of stimulus, and that these were greater for the specific response. The principal pigment component identified was hemosiderin. Results suggest that the intensity of the MMC response in O. niloticus depended on the type of inflammatory stimulus used, and that it was greater in fish inoculated with BCG, which induced a granulomatous inflammation when compared to the foreign body inflammatory response induced by the glass coverslips.     

Human-mediated introgression of exotic chukar (Alectoris chukar, Galliformes) genes from East Asia into native Mediterranean partridges

Mediterranean red-legged (Alectoris rufa) and rock (Alectoris graeca) partridge populations are affected by genetic pollution. The chukar partridge (Alectoris chukar), a species only partly native to Europe, is the most frequently introgressive taxon detected in the genome of hybrid partridges. Both theoretical (evolutionary) and practical (resources management) matters spur to get insight into the geographic origin of the A. chukar hybridizing swarm. The phenotypic A. rufa populations colonizing the easternmost part of the distribution range of this species, the islands of Elba (Italy) and Corsica (France), were investigated. The analysis of both mitochondrial (mtDNA: Cytochrome-b gene plus Control Region: 2,250 characters) and nuclear (Short Tandem Repeats, STR; Random Amplified Polymorphic DNA, RAPD) genomes of 25 wild (Elba) and 20 captive (Corsica) partridges, disclosed spread introgression of chukar origin also in these populations. All mtDNA haplotypes of Elba and Corsica partridges along with those we obtained from other A. rufa (total, n = 111: Italy, Spain, France) and A. graeca (n = 6, Italy), were compared with the mtDNA haplotypes of chukars (n = 205) sampled in 20 countries. It was found that the A. chukar genes detected in red-legged (n = 43) and rock partridges (n = 4) of Spain, France and Italy as well as in either introduced (Italy) or native (Greece, Turkey) chukars (n = 35) were all from East Asia. Hence, a well-defined geographic origin of the exotic chukar genes polluting the genome of native Mediterranean A. rufa and A. graeca (inter-specific level) as well as A. chukar (intra-specific level), was demonstrated.     

Karyotypic differentiation via 2n reduction and a finding of a case of triploidy in anurans of the genus <Emphasis Type="Italic">Engystomops</Emphasis> (Anura,Leiuperidae)

The genus Engystomops is divided into two groups, namely the Duovox clade and the Edentulus clade. The species of Edentulus clade have karyotypes with 2n = 22, while E. pustulatus and E. puyango, which belong to Duovox clade, have 2n = 20. To investigate if 2n = 20 is a synapomorphy of Duovox clade, we cytogenetically analyzed all the species of this group, except for E. puyango, in the present study. All of them had 2n = 20, differing from the species of Edentulus clade. Since the species already karyotyped of the genus Physalaemus, which is considered to be the sister group of Engystomops, also have 2n = 22, we conclude that the 2n reduction is a synapomorphy of Duovox clade. Despite the karyotypes of all the species of Duovox clade were very similar, they varied in the NOR pattern. In E. coloradorum, an additional NOR was found in one homologue of the chromosome pair 10 exclusively in all females, indicating that this could possibly be a sexual pair of the ZZ/ZW system. Also in this species, it was found the first case of natural polyploidy of the genus Engystomops.     

Diet of two commercially important shark species in the United Arab Emirates: milk shark,Rhizoprionodon acutus (Rüppell, 1837), and slit‐eye shark,Loxodon macrorhinus (Müller & Henle, 1839)

The diets of the milk shark, Rhizoprionodon acutus, and the slit‐eye shark, Loxodon macrorhinus, landed from the artisanal fishery in the Arabian Gulf waters of the United Arab Emirates were investigated to determine their dietary preferences. Stomach contents from 57 milk sharks and 53 slit eye sharks were collected from Abu Dhabi (R. acutus, n = 23), Dubai (R. acutus, n = 5; L. macrorhinus, n = 15) and Ras Al Khaimah (R. acutus, n = 29; L. macrorhinus, n = 38) during fishery surveys from January to May 2012. Prey items were identified to the lowest possible taxonomic level, grouped into five categories including ‘teleost fish’, ‘cephalopods’, ‘crustaceans’, ‘invertebrates’, and ‘other’. The diets of both species were described using the numeric, frequency and weight methods, and the index of relative importance (IRI). The majority of stomachs for both species had food, with 66.6% of milk shark stomachs and 90.5% of slit‐eye shark stomachs containing prey items, both dominated by small teleosts. Rhizoprionodon acutus fed on a wide variety of teleost species, primarily Engraulidae (anchovies) (28%), Gerreidae (mojarras) (5.6%) and Carangidae (jacks) (1.6%) with occasional crustacean and cephalopod prey (8%). On the other hand, L. macrorhinus seemed to have a preference for one species in terms of teleosts (anchovies) (35.1%) and fed on a wider variety of crustaceans and cephalopods (22.6%). There was little overlap in the diets of these two species, suggesting that they may either be using different habitats or that in these waters, the milk shark is a generalist species while the slit‐eye is a specialist feeder.     

Pollen and stomata morphometrics and polyploidy in Eriotheca (Malvaceae‐Bombacoideae)

Approximately 70% of the angiosperm species are polyploid, an important phenomenon in the evolution of those plants. But ploidy estimates have often been hindered because of the small size and large number of chromosomes in many tropical groups. Since polyploidy affects cell size, morphometric analyses of pollen grains and stomata have been used to infer ploidy level. Polyploidy is present in many species of the Cerrado, the Neotropical savanna region in Central Brazil, and has been linked to apomixis in some taxa. Eriotheca gracilipes and Eriotheca pubescens are common tree species in this region, and present cytotypes that form reproductive mosaics. Hexaploid individuals (2n = 6x = 276) are polyembryonic and apomictic, while tetraploid and diploid individuals (2n = 2x = 92, 2n = 4x = 184) are sexual and monoembryonic. We tested whether morphometric analysis can be used to estimate ploidy levels in E. gracilipes and E. pubescens individuals. Pollen material from diploid and hexaploid individuals of E. gracilipes, and tetraploid and hexaploid individuals of E. pubescens, were fixed in 50% FAA, and expanded leaves were dried in silica gel. Pollen grains and stomata of at least five individuals from each population were measured. The results demonstrate that all measures were significantly different among cytotypes. Individuals with higher levels of ploidy (hexaploid) all presented measurements that were higher than those with lower levels (diploid and tetraploid). There was no overlap between ploidy levels in each species at 95% confidence interval. Thus, the size of the pollen grains and stomata are effective parameters for analysis of ploidy levels in E. gracilipes and E. pubescens.