In vitro Development of Buffalo Oocytes in Media-containing Fluids from Different Size Class Follicles

Studies were conducted to investigate the effect of supplementation of fluid from different sized class [small (SFF, < 3 mm), medium (MFF, 3-8 mm) and large (LFF, > 8 mm)] of normal and cystic (CFF) ovarian follicles in oocyte culture media on oocyte maturation rate and embryo development in vitro and to test the efficacy of follicular fluid (FF) from different size classes as a whole oocyte maturation medium. Results suggested that FF were capable of developing buffalo oocytes to embryonic stage in vitro although its efficacy was lower than that of serum. Regardless of high maturation rates after in vitro maturation (IVM) in media containing FF or IVM in whole FF, low blastocyst rates were obtained after in vitro fertilization (IVF) and culture of embryos. Follicular fluid from small follicles had significantly (p < 0.05) higher potential of developing buffalo oocytes to embryonic stage in vitro than that from medium and large follicles. Cystic FF was not capable of supporting development of buffalo oocytes in vitro.     

Management of the female stimulus during semen collection and its association with libido re-establishment and semen characteristics of goats

The effect of management of the female stimulus during semen collection and its association with libido re-establishment and the semen characteristics of sexually mature goats was evaluated. Eight 2-yr-old bucks were individually subjected to 12 weekly trials in which one of the following three treatments was applied alternately. In treatment one, each male performed two ejaculations on an estrus-induced, restrained doe and semen was collected with an artificial vagina (AV). In treatment two, males were collected as in the former treatment, but a different doe served as the stimulus female for the second ejaculation. In treatment three, two restrained does were present while collecting each buck, allowing males to choose which female to mount and serve in each of the two collections. Number of mounts before first ejaculation and reaction times (period from introduction of the ram to the test arena to his first ejaculation) were similar among treatments (P > 0.05). A significant (P < 0.05) decrease was found for number of mounts performed before achieving the second ejaculation and for latency between ejaculations in the third treatment. No differences (P > 0.05) were found for semen volume (0.8+/-0.03, 1.0+/-0.03, and 0.9+/-0.02 mL) or sperm concentration (4.4+/-0.15, 4.6+/-0.13, and 4.4+/-0.86 spermatozoa/mL) among the three treatments or between the first and second collection. However, a trend to decrease volume and concentration was observed. It was concluded that the simultaneous presence of two females while bucks are collected reduced the number of mounts performed before the second ejaculation and the latency between ejaculations.     

Development of Dermanyssus gallinae (Acari: Dermanyssidae) at different temperatures

The development, viability, and life cycle parameters of Dermanyssus gallinae at five different temperatures (15, 20, 25, 30 and 35 degrees C), and at relative humidity 70-85% were evaluated. Life cycle duration was 690.75 h (28 days) at 15 degrees C, 263.12h (11 days) at 20 degrees C, 164.63 h (7 days) at 25 degrees C, 140.69 h (6 days) at 30 degrees C and 172.04 h (7 days) at 35 degrees C. The optimal development temperature for D. gallinae was 30 degrees C, with the greatest survival in all stages and the shortest development time. High mortality at 35 degrees C indicated that this temperature had adverse effects on development of D. gallinae, and that in field conditions D. gallinae populations may decrease or even disappear due to the negative impact of high temperature on development. There were no significant differences in the pre-oviposition period among the four temperatures 20-35 degrees C, indicating that temperature did not affect this part of the life cycle.     

General and specific combining ability in Serrasalmidae

This work was carried out to predict the combining abilities, both general and specific, for performance traits and bodily yields of Serrasalmidae. Ninety‐six 30‐day‐old juveniles were purchased from two commercial fish farms, 12 of each of the following eight genetic groups: pacu, pirapitinga, tambaqui, tambacu, tambatinga, patinga, paqui and piraqui. Six fish from each genetic group were grown in 500‐L fibreglass tanks (two tanks per genetic group) until they were 495 days old. At the end of the growth period fish were weighed, subjected to morphometric analysis and processed to obtain their bodily yields. Two nuclear markers and one mitochondrial marker were used to confirm the identity of the animals. Combining abilities were obtained using the method proposed by Griffing in 1956 (Australian Journal of Biological Science, 4, 463–493) adapted to a mixed models analysis, environmental effects were estimated by the empirical best linear unbiased estimator method and genetic effects (general and specific combining abilities) were estimated with the empirical best linear unbiased predictor. Predictions of the combining abilities of advanced hybrids were obtained by the mixed models mixture method with normal distributions. Tambaqui showed higher general and specific combining abilities than the other groups for most of the variables, making it the most important genetic group. General combining ability makes a greater contribution to phenotypic variance than specific combining ability for most variables, indicating a predominance of genes with an additive effect in the control of evaluated traits.     

Effect of clove (Eugenia caryophyllus) and cinnamon (Cinnamomum zeylanicum) essential oils in Nile tilapia diets on performance,antioxidant power and lipid oxidation in fillets

This study evaluated the addition (0.35 and 0.70 g/kg feed) of clove (EOcl) or cinnamon (EOci) essential oils to Nile tilapia feed for 45 days to assess animal performance, antioxidant capacity and lipid oxidation in fillets. The design was completely randomised with five treatments and three replicates. Antioxidant capacity was determined by the oxygen radical absorbance capacity (ORAC_FL), 2,2‐diphenyl‐1‐picrylhydrazylhydrate (DPPH), ferric reducing ability power (FRAP) and 2,2’‐azino‐bis (3‐ethylbenzothiazoline‐6‐sulphonic acid) (ABTS) assays, and lipid oxidation was determined by the thiobarbituric acid‐reactive substances (TBARs) assay. Animal performance was not altered by adding the essential oils. The fillets treated with 0.35 g/kg of EOcl presented higher antioxidant capacity in the L‐ORAC_FL assay and a 40.3% reduction in lipid oxidation, whereas the EOci provided a pro‐oxidant effect relative to the control treatment. Based on these results, adding 0.35 g/kg of EOcl to the diet for 45 days before slaughter increased the antioxidant capacity and reduced the lipid oxidation of the fillets, contributing to product quality without altering animal performance.     

Cellular Composition and Viability of Cloned Bovine Embryos Using Exogene-Transfected Somatic Cells

The present study compared the efficiency of transgenic (TG) cloned embryo production by somatic cell nuclear transfer (SCNT) with fetal-derived fibroblast cells (FFCs) which were transfected with pEGFP-N1 to in vitro-fertilized (IVF), parthenogenetic and SCNT counterparts by evaluating the rates of cleavage and blastocyst formation, apoptosis rate at different developmental stages, cell number, ploidy and gene expression in blastocysts. In SCNT and TG embryos, the rates of cleavage and blastocyst formation were significantly lower (p < 0.05) than those of IVF controls, but it did not differ between SCNT and TG embryos. In IVF control, 86.7% embryos displayed diploid chromosomal complements and the rates were significantly (p < 0.05) higher than those of SCNT and TG embryos. Most TG embryos (79%) with FFCs expressed the gene by both PCR and under fluorescence microscopy. The expression of apoptosis by TUNEL was first detected at six to eight cell stages in all embryos of IVF, SCNT and TG groups, but the expression rate at each developmental stages was significantly higher (p < 0.05) in SCNT and TG embryos than in IVF counterparts. The expression rate in inner cell mass (ICM) of TG embryos was significantly higher (p < 0.05) than in SCNT and IVF embryos. These results indicate that the high occurrence of apoptosis observed in SCNT and TG embryos compared with IVF counterparts might influence the developmental competence. Moreover, the SCNT embryos derived using non-transfected donor cells exhibited a lower apoptosis expression in ICM cells than in TG embryos derived using pEGP-N1-transfected donor cells suggesting a possible role of negative gene effect in TG embryos.     

Comparison of inhibitory activity of amides derivatives in triazine-resistant and -susceptible chloroplasts from Chenopodium album and Brassica campestris

Half-inhibitory concentrations of some substituted ureas and other amide derivatives were measured in chloroplasts extracted from triazine-resistant and -susceptible biotypes of Chenopodium album and Brassica campestris. It was shown that the binding contribution weakened in triazineresistant chloroplasts was not hydrophobic. The existence of two independent interactions could be deduced from their differential behavior toward triazine resistance. A nitrogen-dependent interaction, possibly involving an acidic proton, is preferentially affected by triazine resistance, whereas a carbonyl-dependent interaction maintains its contribution to binding. Analogies with triazine behavior could be shown, which are compatible with an identity of electronic binding components at the site of action of amide derivatives and triazines.     

Analysis on the daily courses of water potential of nine woody species from Cerrado vegetation during wet season

IntroductionAS the concept of water pot6ntial (% was introduced by Saltyer (1967), there were some argumentson it among some physiologist. Some physiologistsopposed it beCause they believed Tvalue might notbe the beSt parameter for describing physiologicalprocesses. However, this concept has been accept6dand used by most plant physiologists for many years(Kramer 1988, Schulze et al. 1988, Passioura 1988,Boyer 1989).ACcording tO our experience (Prado et al. 1994,1995), we believed-t.hat th…     

Methane emission of Santa Inês sheep fed cottonseed by-products containing different levels of gossypol

The aim of this study was to evaluate the methane (CH₄) emission of Santa Inês sheep fed cottonseed by-products, verifying if the gossypol content of these feedstuffs affects CH₄ emission. Twelve late-lactating Santa Inês sheep (44.8?±?7.5 kg body weight (BW)) were allocated in metabolic cages for an experimental period of 19 days, 14 days for adaptation and 5 days for measuring CH₄ emission and dry matter intake (DMI). The animals were divided into four treatments, established in accordance with the cottonseed by-product used in concentrate formulation: Control (CON - no cottonseed by-product), Whole cottonseed (WCS), Cottonseed cake (CSC), and Cottonseed meal (CSM). The free gossypol level of the concentrates were 0, 1,276, 350, and 190 ppm for CON, WCS, CSC, and CSM, respectively. Also, the animals received Cynodon dactylon cv. Coast Cross hay, water, and mineral salt ad libitum. The ether extract content of the diets was balanced between treatments by including soybean oil in concentrates. The technique used to measure the CH₄ emission was the sulfur hexafluoride (SF₆) tracer technique, and the gas samples collected were quantified by analysis in gas chromatography system. The CH₄ emission was evaluated considering the daily emission (g CH₄/day); DMI (g CH₄/kg DMI); and BW (g CH₄/kg BW). No statistical difference was found (P?>?0.05) between treatments for DMI and CH₄ parameters. In the regression analysis, no significant relation (P?>?0.05) between gossypol content and CH₄ emission was observed. These results suggest that gossypol does not affect rumen methanogenesis.