In ovo injection of ascorbic acid and higher incubation temperature modulate blood parameters in response to heat exposure in broilers

1. This study analysed whether in ovo injection of ascorbic acid before incubation and at high incubation temperature influenced blood characteristics and performance in broilers reared in different temperature conditions.

2. A total of 3,000 fertile eggs from broiler breeders (Cobb®) were randomly divided into three incubation treatments: no ascorbic acid injection and egg incubation at 37.5°C (control); no ascorbic acid injection and egg incubation at 39°C; in ovo ascorbic acid injection prior to incubation (6 µg AA/100 µl water) and egg incubation at 39°C.

3. Male chicks hatched from the three incubation treatments were submitted to three distinct rearing temperatures (control, cold and hot) from the third week of age onwards (540 chicks were divided into 6 treatments with 5 replicates per treatment).

4. Measurements at 42 d showed that, after egg incubation at 39°C, the haematocrit, haemoglobin values, ionised calcium and glucose concentrations were increased and base excess values were reduced. However, in ovo injection of ascorbic acid normalised all these parameters.

5. Partial CO₂ and O₂ pressure were higher with increased rearing temperature. Blood pH was lower when eggs were incubated at 39°C and injected with ascorbic acid. In ovo injection of ascorbic acid induced leucocytosis due to lymphocytosis and heterophilia, restored basophils rate and led to monocytopoenia. Leucocytosis was triggered by hot rearing temperature due to lymphocytosis, eosinophilia and heterophilia.

6. The results obtained in this study showed that in ovo injection of ascorbic acid before incubation may serve as a long-term stimulator and modulator of the broiler immune system, and that high incubation temperatures induce adaptations in the electrolytic balance, minimising or avoiding the occurrence of respiratory alkalosis under hot rearing temperature.     

Effects of tumour necrosis factor‐alpha and interleukin‐1 beta on in vitro development of bovine secondary follicles

The objective of this study was to determine the effects of TNF‐α and IL‐1β on development and survival of bovine secondary follicle culture in vitro for 18 days. Secondary follicles (~0.2 mm) were isolated from ovarian cortex and individually cultured at 38.5°C, with 5% CO₂ in air, for 18 days, in TCM‐199⁺ alone (cultured control) or supplemented with 10 ng/ml IL‐1β, 10 ng/ml TNF‐α or both TNF‐α and IL‐1β. The effects of these treatments on growth, follicular survival, antrum formation, viability, ultrastructure and mRNA levels for GDF‐9, c‐MOS, H1foo and Cyclin B1 were evaluated. The results showed that addition of TNF‐α to culture medium increased follicular diameter and rate of antrum formation, whereas that of IL‐1β and a mixture of IL‐1β and TNF‐α did not do so. Ultrastructural analysis showed that, among the tested cytokine treatments, follicles cultured in the presence of TNF‐α had the best‐preserved oocytes and granulosa cells. The presence of TNF‐α, IL‐1β or both did not influence the expression of mRNAs analysed. In conclusion, in contrast to IL‐1β, TNF‐α promotes growth of and antrum formation in in vitro cultured bovine secondary follicles, while their ultrastructure and viability were maintained.     

Use of protocatechuic acid as the sole antioxidant in the base medium for in vitro culture of ovine isolated secondary follicles

This study evaluated the effect of the protocatechuic acid (PCA) as the sole antioxidant in the base medium for in vitro culture of ovine secondary follicles. Secondary follicles (200‐230 μm) were isolated and cultured in α‐minimal essential medium supplemented with BSA, insulin, glutamine and hypoxanthine (α‐MEM: antioxidant‐free medium) or α‐MEM also added by transferrin, selenium and ascorbic acid (α‐MEM+: with antioxidant) or α‐MEM added by PCA (56.25; 112.5; 225; 450; or 900 μg/ml). Moreover, after culture, oocytes were matured and the chromatin configuration and DNA fragmentation were evaluated. After 12 days, the treatment containing 56.25 μg/ml PCA showed higher percentage of normal follicles than control medium or the other treatments (p < .05), except for 900 μg/ml PCA (p > .05). The antrum formation was significantly higher in treatments containing 56.25, 112.5 or 900 μg/ml PCA, compared to the α‐MEM and similar (p > .05) to the other treatments. The rates of fully grown oocytes (≥110 μm) were similar (p > .05) among all treatments containing PCA and α‐MEM+, and those were superior (p < .05) than α‐MEM, except for 450 μg/ml PCA (p > .05). GSH levels and mitochondrial activity were higher (p < .05) in α‐MEM+ than in α‐MEM and similar (p > .05) to all PCA treatments. The rates of meiotic resumption and DNA fragmentation were similar (p > .05) among α‐MEM+ and 56.25 μg/ml PCA. In conclusion, PCA at 56.25 μg/ml as the sole antioxidant added to the medium for ovine isolated secondary follicle culture maintains follicular survival, GSH and active mitochondria levels, meiotic developmental competence and DNA integrity of cultured oocytes.     

Two-dimensional echocardiographic estimates of left atrial function in healthy dogs and dogs with myxomatous mitral valve disease

Objectives

To provide reference intervals for 2-dimensional linear and area-based estimates of left atrial (LA) function in healthy dogs and to evaluate the ability of estimates of LA function to differentiate dogs with subclinical myxomatous mitral valve disease (MMVD) and similarly affected dogs with congestive heart failure (CHF).

Interspecific competition changes nutrient : nutrient ratios of weeds and maize

The elemental ratios of plant tissues are associated with the adaptive and competitive success of a plant species in an ecosystem. So far, no study has evaluated if and how crop–weed competition influences the elemental ratios of competing populations, although such information is important to understand weed infestation dynamics and to improve weed management in agroecosystems. The objective of this study was to analyze weed–crop elemental ratios during interspecific competition between weeds and crops in greenhouse experiments. For this, maize (Zea mays L.) and the weeds Amaranthus viridis L, Bidens pilosa L., and Ipomoea grandifolia (Dammer) O'Donell were grown under seven treatments: maize and weed monocultures, and maize in competition with weeds. Competition between plants practically did not influence growth and nutrient contents of maize but reduced weed growth and nutrient uptake. Maize showed few changes in elemental ratios. In contrast, B. pilosa and I. grandifolia were very sensitive to competition and showed significant increases in C : N, C : P, C : K, N : P, and N : K ratios when grown with maize. A. viridis showed low flexibility of nutrient : nutrient ratios under the same competitive pressure as that faced by B. pilosa and I. grandifolia. The interspecific competition led to increases only in the C : P ratio of A. viridis shoots. Therefore, interspecific competition changes the elemental ratios, mainly of the weeds, and the magnitude of this change is dependent on the plant species involved. Interspecific competition changes plant biomass quality (higher C : nutrient ratios), mainly for B. pilosa and I. grandifolia.     

Electron paramagnetic resonance (EPR) spectroscopy as a tool for the characterization of biochar from guava waste

Journal of Soils and Sediments - The ability of biochars prepared from pyrolysis of guava pulp and seed industrial wastes to form complexes with the ions vanadyl (VO2+), a Pearson hard acid, and...     

Essential oils from Cymbopogon citratus and Lippia sidoides in the anesthetic induction and transport of ornamental fish Pterophyllum scalare

Fish Physiology and Biochemistry - This study verified the effects of essential oils from Lippia sidoides (EOLS) and Cymbopogon citratus (EOCC) on the anesthesia of freshwater angelfish...     

Glycerol,Methyl‐Formamide and Dimethyl‐Formamide in Canine Semen Cryopreservation

The aim of the present work was to compare the efficiency of methyl‐formamide (MF), dimethyl‐formamide (DF) and glycerol (GL) as cryoprotectants in canine semen cryopreservation. For the experiment, pooled semen was submitted to one of the three cryoprotectants, with a final concentration of 3% in egg yolk–TRIS extender. Semen was subjectively evaluated for total and progressive motility, vigour and morphology. Sperm membrane functional integrity was assessed by hypo‐osmotic swelling test (HOST), and longevity was assessed using the thermoresistance test (TRT). Fresh semen showed normal physical and morphological characteristics. After thawing, differences were observed between semen frozen using GL and DF, regarding total and progressive motility and vigour (p < 0.05), but not between MF and GL or MF and DF. Means for total motility, progressive motility, vigour and morphologically normal spermatozoa were, respectively, 69.0 ± 5.4%, 61.0 ± 7.4%, 2.9 ± 0.5 and 57.1 ± 5.0% for GL; 59.0 ± 8.9%, 50.0 ± 10.0%, 2.5 ± 0.7 and 66.9 ± 7.7% for MF; and 44.0 ± 21.0%, 37.0 ± 19.8%, 2.1 ± 0.6 and 61.1 ± 5.5% for DF. On HOST, GL was superior (p < 0.05) to MF and DF (57.8 ± 12.4%, 35.8 ± 18.4% and 34.4 ± 9.4%, respectively). During the TRT, both GL and MF were superior to DF, with no differences between GL and MF. In conclusion, the use of MF as cryoprotectant showed results similar to GL, and can be considered as an alternative in canine semen cryopreservation. Further studies testing different concentrations of MF may improve its effects on cryopreservation of canine semen.