Ivana Cristina Nunes Gadelha

Gossypol Toxicity from Cottonseed Products

Gossypol is a phenolic compound produced by pigment glands in cotton stems, leaves, seeds, and flower buds (Gossypium spp.). Cottonseed meal is a by-product of cotton that is used for animal feeding because it is rich in oil and proteins. However, gossypol toxicity limits cottonseed use in animal feed. High concentrations of free gossypol may be responsible for acute clinical signs of gossypol poisoning which include respiratory distress, impaired body weight gain, anorexia, weakness, apathy, and death after several days. However, the most common toxic effects is the impairment of male and female reproduction. Another important toxic effect of gossypol is its interference with immune function, reducing an animals resistance to infections and impairing the efficiency of vaccines. Preventive procedures to limit gossypol toxicity involve treatment of the cottonseed product to reduce the concentration of free gossypol with the most common treatment being exposure to heat. However, free gossypol can be released from the bound form during digestion. Agronomic selection has produced cotton varieties devoid of glands producing gossypol, but these varieties are not normally grown because they are less productive and are more vulnerable to attacks by insects.

Pesticide exposure of honeybees (Apis mellifera) pollinating melon crops

The decline of honeybee (Apis mellifera L.) populations impacts global agricultural production and affects both food production and the economy. One of the probable causes for this decline is the indiscriminate use of pesticides. Here, we compare the levels of pesticide exposure among honeybees that are used to pollinate melon (Cucumis melo L.) crops, honeybees that forage in the forest, and stingless bees, Melipona subnitida, that forage in the forest. The level of pesticide exposure was determined by measuring residual pesticide levels of 152 compounds in the honey. Honey samples from the present study contained 19 different pesticides, 13 of which were present in honey from bees pollinating melon crops. The levels of some compounds were sufficiently high to promote toxic effects in the bees. Thus, crop pollination presents a toxicological risk to bees that may reduce their life span.

Toxicity of Gossypol from Cottonseed Cake to Sheep Ovarian Follicles

Gossypol, a polyphenol compound produced by cotton plant, has proven reproductive toxicity, but the effects of gossypol on sheep ovaries are unknown. This study was aimed to determine the in vitro and in vivo effects of gossypol on the ovarian follicles of sheep. This trial was divided into two experiments. In the first one, we used twelve non-pregnant, nulliparous, Santa Inês crossbred ewes, which were randomly distributed into two equal groups and fed diets with and without cottonseed cake. Feed was offered at 1.5% of the animal’s body weight for 63 days. The concentrations of total and free gossypol in the cottonseed cake were 3.28 mg/g and 0.11 mg/g, respectively. Throughout the trial period, no animal showed clinical signs of toxicity and no effects on body weight were observed. However, there was a significantly lower number of viable ovarian follicles (20.6%) and higher number of atretic follicles (79.4%) in the gossypol-fed sheep compared to the control (85.1 and 34.9%, respectively). These findings were observed at all stages of follicular development. In the second experiment, eight ovaries from slaughterhouse were cultured with different concentrations of gossypol acetic acid (0, 5, 10 and 20 μg/mL) for 24 hours or seven days. The in vitro action of gossypol resulted in a significant decrease in viable ovarian follicles, especially the primary and transition follicles, and a significant increase in the number of atretic follicles after 24 hours of culture. These follicles were greatly affected when cultured with gossypol for seven days. It is concluded that gossypol present in cotton seeds directly acts on ovarian follicles in sheep to increase atresia.

Gossypol Promotes Degeneration of Ovarian Follicles in Rats

The present study aimed to determine if gossypol interferes with ovarian follicles in rats. Twenty-four female Wistar rats were assigned to two equal groups: one control group and the other dosed with gossypol (25 mg/kg/day, subcutaneously) for 15 days. Ovarian follicles were histologically classified according to the stage of development and as normal or atretic. Gossypol treatment reduced the length of estrous with an increase in the duration of the diestrus phase. This compound was responsible for reduced serum levels of T4 and progesterone. Treatment with gossypol was responsible for a significant reduction in the number of normal ovarian follicles and a significant increase in the number of atretic follicles, both in all stages of development. Thus, treatment of rats with gossypol was responsible for reduction in the number of viable follicles and changes in hormone levels that resulted in interference of the estrous cycle.

Embryotoxic effects of Poincianella ( Caesalpinia) pyramidalis leaves on pregnant rats.

We investigated the embryotoxic and fetotoxic effects of Poincianella pyramidalis (Tul.) L.P. Queiroz (syn. Caesalpinia pyramidalis Tul.) leaves on pregnant rats (Rattus norvegicus). Pregnant rats were divided into 4 groups: G1—fed a ration containing 5% P. pyramidalis leaves beginning on day 1 of pregnancy; G2—fed a ration containing 5% P. pyramidalis leaves commencing on day 6 of pregnancy; G3—fed a ration containing 10% P. pyramidalis leaves starting on day 6 of pregnancy; G4—control group. On day 21 of pregnancy, parameters of reproductive performance were recorded. Fetal growth was measured, and fetuses were subjected to external examination and identification of skeletal anomalies. Rations containing P. pyramidalis resulted in dead or undeveloped fetuses and reduced the number, length, and weight of the fetuses. Rations also increased postimplantation losses and the frequency of skeletal anomalies. Furthermore, P. pyramidalis was also responsible for dose-dependent lesions in the placentas. In conclusion, the ingestion of P. pyramidalis promotes fetal and placental damage.

Effectiveness of albumin-conjugated gossypol as an immunogen to prevent gossypol-associated acute hepatotoxicity in rats.

Gossypol is a highly reactive compound present in cotton (Gossypium spp.). The aim of this work was to determine whether the administration of gossypol conjugated to albumin can immunize rats and thereby prevent the acute hepatotoxicity associated with gossypol. The first experiment consisted of administering the immunogen gossypol-BSA, with or without the Freunds incomplete adjuvant, to rats. The production of antibodies against gossypol was subsequently verified. The second experiment comprised three groups of Wistar rats: VG, CG and CO. The rats from the VG cohort were injected with gossypol-BSA associated with Freunds incomplete adjuvant, and the animals from the CG and CO groups were injected with saline solution. After 21 days, the rats from the VG and CG cohorts were treated with 30 mg/kg of gossypol by intraperitoneal injection, whereas the rats from the CO group received corn oil. After 24 h, the rats were evaluated for clinical signs of pathology, and their serum was biochemically analyzed. It was found that gossypol promoted hepatotoxic effects that were not prevented by the administration of gossypol-BSA. In conclusion, the administration of gossypol-BSA associated with Freunds incomplete adjuvant may be lightly to prevent the acute hepatotoxicity associated with gossypol.

Toxicity Effects of Toad (Rhinella jimi Stevaux, 2002) Venom in Chicken (Gallus gallus domesticus)

This study aimed to evaluate the pathological changes that occur after administering different doses of R. jimi (Stevaux, 2002) parotoid glands secretion to Gallus gallus domesticus chicks. Twenty-three animals were used in this study and were divided into 5 groups that received a toad venom dose of 0, 3.0 mg/kg, 6.0 mg/kg, 10.0 mg/kg, and 25.0 mg/kg. After 48 h, the necropsy and pathological examinations were performed. No clinical signs of toxicity were observed in any group. Macroscopically, hepatomegaly, areas of liver necrosis, splenomegaly, necrotic and hemorrhagic cardiac regions, hydropericardium, dark necrotic lesions of Meckels diverticulum, and hemorrhages in the lungs and kidneys were detected. Histopathological changes included diffuse vacuolar degeneration of hepatocytes, severe sinusoidal congestion, focal areas of hemorrhage in the parenchyma, swollen cardiac fibers, necrotic myocardial fibers, moderate to acute diffuse alveolar hemorrhage, vacuolar degeneration of the renal tubular epithelium, necrosis of renal tubules, and extensive hemorrhagic areas below the brain and cerebellar meninges. In conclusion, pathological changes of the R. jimi toxins in chicks were noted in the heart, spleen, liver, Meckels diverticulum, lungs, and kidneys. Most of the changes were similar to those observed in humans and animals exposed to toxins from other toad species.

In vitro study of gossypol's ovarian toxicity to rodents and goats

ABSTRACT Gossypol interferes with reproduction, causing damage to sperm, disrupting the estrous cycle and resulting in embryonic lethality. In females, gossypol administration promotes degeneration of ovarian follicles, but it is unknown whether this effect is direct or indirect. Thus, the aim of this study is to determine whether gossypol interferes with folliculogenesis in vitro in rats, mice and goats. Ovaries from rats and mice and fragments of goat ovaries were grown in cell culture for 24 h or 7 days. Four groups were tested: 0 (control), 5, 10 and 20 &mgr;g gossypol/ml. After incubation, the ovaries were fixed and processed for histological analysis. Follicles were classified according to their stage of development as either viable or atretic. It was found that the ovaries of rats, mice and goats cultured with gossypol showed an increase in the proportion of atretic follicles and a consequent reduction in the proportion of viable follicles at all stages of follicular development. Compared to the control group, the viability of all ovarian follicles in the rat, mouse and goat groups was reduced after cultivation for 24 h by 56.9%, 56.5% and 68.0%, respectively, with the highest concentration of gossypol (20 &mgr;g/mL), and after seven days, the respective reductions were 65.4%, 65.3% and 88.2%. Thus, it is possible that gossypol may directly affect follicular maturation, and consequently female fertility. HighlightsGossypol is well known to cause toxic effects in male reproduction.Its effects on female reproduction have been minimally described.Gossypol at 5, 10 and 20 &mgr;g/mL promotes direct damage to the ovarian follicles.The proportions of atretic follicles were increased at all stages of development.

ACHADOS CLÍNICO-EPIDEMIOLÓGICOS DE 25 CASOS DE CÓLICA EM EQUÍDEOS NO RIO GRANDE DO NORTE

The present article aimed to conduct a retrospective study of the main clinical and epidemiological findings in 25 cases of colic in equidae from Rio Grande do Norte. Twenty five equidae (21 horses, three mules and one donkey) were included. Clinical treatment was performed in 15 equidae with moderate large colon impaction (n = 6), cecal bloat (n = 4), gastric overload (n = 3), cecal impaction (n = 1) and gastric ulcers (n = 1). Six horses with severe large colon impaction (n = 2), meconium impaction (n = 2), left dorsal displacement of the large colon (n = 1) and verminotic arteritis (n = 1) were submitted to exploratory laparotomy. Four horses were not treated due to severe systemic disturbances and poor prognosis. Higher incidence occurred in Quarter horses and crossbreed horses followed by mules and single cases in a pony and a donkey. Impactions of the large intestine and cecal bloat were the major causes of colic in equidae from this study; and mainly resulted from erroneous feeding management by the owners or handlers.