Cycad (zamia) poisoning in Australia

The Cycads belong to an ancient family of plants and were the cause of the first well documented plant poisoning in Australia when Captain Cook's men and their pigs were affected by eating them. Subsequent reports particularly by early explorers refer to toxicity of the seeds to man. One reason for this was the evidence that the natives ate them. Subsequent reports and experimental work established the toxicity to sheep and cattle. In sheep and cattle 2 syndromes occur, ataxia and liver damage. In cattle the former is the better known, the spinal cord lesion being mainly a demyelination of the sensory pathways. The liver damage is necrosis and fibrosis.     

Hound's-tongue (Cynoglossum officinale) poisoning in a calf

Cynoglossum officinale was believed to be responsible for the death of one calf and possibly 5 other calves in a group of 9 calves being fed chopped hay contaminated by this plant. The plant, commonly known as hound's tongue, contains pyrrolizidine alkaloids and has been determined to be toxic to horses fed contaminated hay, but was fed to cattle at the same time with no effect.     

Oak leaf (Quercus pyrenaica) poisoning in cattle

Three experiments were conducted to study the clinical and pathological findings associated with poisoning in cattle due to ingestion of young oak leaves (OL) and the main factors responsible for toxicosis. In Experiment 1, six 1.4 year-old bulls were fed up to 5 kg of young OL per animal per day and showed no signs of toxicity, apart from a slight proteinuria. In Experiment 2, another six 1.4 year-old bulls were first subjected to severe feed restriction for eight days and then fed a higher amount of OL (approx. 10 kg) daily. A marked increase of serum creatinine and blood urea (BUN) was detected in urine as well as clinical signs consistent with renal failure. At necropsy, animals showed gastrointestinal ulcers and kidney tubular necrosis. Since these results suggested a crucial role of the feed restricting period, a third experiment was conducted administering the same amount of young OL as in Experiment 1, but adding the severe feed restricting period as in Experiment 2. There was a wide variation in clinical signs, with one bull showing clinical signs and lesions, another recovering after showing mild clinical signs and high levels of creatinine and BUN, and the third appearing clinically normal. The relevance of restriction access to food in the development of OL toxicosis appears to be critical because the intoxication was only elicited when the OL administration was preceded by a severe feed restricting period.     

Nicotiana glauca poisoning in ostriches (Struthio camelus)

Putative Nicotiana glauca (wild tobacco) poisoning was diagnosed in a flock of ostriches near Oudtshoorn, South Africa. Post mortem examinations (n = 7) were performed on ostriches (Struthio camelus) that had died. Suspicious leaf remnants (weighing 80-770 g), packed in a layer on top of other plant material, were carefully separated from the proventricular content and submitted for chemical determination of anabasine, the major toxic principle contained by this plant. A standard solid phase extraction method was used followed by an optimised liquid chromatography-mass spectrometry procedure. Anabasine was detected in the leaf remnants (114-177 microg/g dry weight) removed from the proventriculus of the ostriches that succumbed as well as in control N. glauca leaves (193 microg/g dry weight). The analytical methods used in this study revealed the presence of anabasine in the suspicious leaf remnants, indicating that the birds had been exposed to N. glauca and had died of this poisoning.     

Nitrogen dioxide (silo gas) poisoning in pigs

Toxic silo gases are a potential danger to livestock housed in close proximity to silos. On the fourth day of ensiling, five fattening pigs were found dead in a pen adjoining a grass silo. Post mortem examination revealed extensive lung damage and methaemoglobinaemia. A dense reddish-brown gas was concentrated at floor level to a height of 1 m in the pen and had diffused into adjoining pens, where dry and suckling sows and litters were showing signs of respiratory distress and weakness. The gas was identified as a mixture of nitrogen dioxide and dinitrogen tetroxide. These gases may be produced in the early stages of silage making. In this case, they had accumulated in a slurry channel below the silo and leaked through an adjoining wall into the piggery. The production and toxicological effects of silo gases are discussed.     

Sodium monofluoroacetate (Compound 1080) poisoning in dogs

Sodium monofluoroacetate (Compound 1080) is a widely used pesticide for control of feral animals such as the fox. Accidental poisoning of domestic animals occurs despite strict regulations on 1080 usage. Dogs are particularly susceptible to the toxin. The mechanism of 1080 toxicity, susceptibility of target and non-target species, persistence of 1080 in the environment and risk of accidental poisoning are discussed. Particular emphasis is placed on 1080 toxicity in the dog. Early recognition of intoxication is most important for prognosis and relies upon characteristic clinical signs and diagnostic findings. The treatment of 1080 intoxication remains a challenge with no proven antidotes. However, there are possible benefits from monoacetin, acetamide, calcium salts, colestipol, activated charcoal, peritoneal dialysis, sodium bicarbonate, neurotransmitter modulators and four-methylpyrazole. A recommended treatment protocol for 1080 toxicosis in dogs is included. Safety measures such as the use of wire dog muzzles and investigating alternatives to 1080 in pest control programs may be the key to reducing the incidence of future accidental poisonings.     

Cestrum parqui (green cestrum) poisoning in cattle

SUMMARY Naturally occurring cases of poisoning of cattle by Cestrum parqui were characterised by ataxia, depression, recumbency, convulsions and death. Three cattle were dosed experimentally by intrarumenal administration of fresh plant material. One calf died 48 h after receiving 30 g (wet weight) of plant /kg body weight. Doses of 11 and 17 g/kg caused only mild intoxication, with dullness and anorexia lasting 2 days. In natural and experimental cases the main lesion was hepatic periacinar necrosis. Elevated levels of plasma aspartate transaminase and prolonged prothrombin times were demonstrated in experimental cases. Haemorrhage beneath the serosa and into the intestinal lumen occurred in field cases, but not in the experimental. It is concluded that C. parqui poisoning in cattle is a primary hepatotoxicity.     

Oxalate poisoning in a koala (Phascolarctos cinereus)

SUMMARY A case of suspected acute oxalate poisoning is reported in an aged male koala. The animal had extensive renal oxalosis and a haemorrhagic bladder wall when autopsied. The source of the oxalate was not detected.     

真姬菇菌糠碱贮效果研究

为了研究真姬菇菌糠碱贮效果,试验采用CaO、Ca（OH）₂、CaO+3%尿素及Ca（OH）₂+3%尿素4种碱贮处理,每种处理碱（CaO或Ca（OH）₂）的添加量设3%、4%、5%及6% 4个水平,分别为CO3、CO4、CO5、CO6,CH3、CH4、CH5、CH6,COU3、COU4、COU5、COU6,CHU3、CHU4、CHU5、CHU6,每个水平4个重复,2个空白组,1组空白（CK）仅为真姬菇菌糠,另1组空白（CKU）为真姬菇菌糠+3%尿素,室温下碱贮30 d。结果表明：CO3、CO4、CO5、CO6组酸性洗涤纤维（ADF）和游离棉酚含量较CK组分别降低8.61%、12.69%、13.74%、16.63%和29.58%、33.92%、39.04%、41.31%,CO5、CO6组中性洗涤纤维（NDF）、酸洗木质素（ADL）含量较CK组显著降低（P<0.05）,可降解细胞壁（CB₂）和相对饲喂价值（RFV）较CK组显著提高（P<0.05）;CH3、CH4、CH5、CH6组ADF和游离棉酚含量较CK组分别降低7.30%、10.90%、13.90%、17.14%和28.47%、32.69%、40.48%、43.59%,CH5、CH6组NDF、ADL含量较CK组显著降低（P<0.05）,CB₂和RFV较CK组显著提高（P<0.05）;COU3、COU4、COU5、COU6组NDF、ADF和游离棉酚含量较CKU组分别降低6.72%、8.86%、9.78%、12.10%;14.63%、16.37%、18.19%、20.21%及5.49%、14.24%、23.63%、24.66%,RFV提高18.97%、23.19%、25.86%、30.79%;CHU3、CHU4、CHU5、CHU6组NDF、ADF、ADL和游离棉酚含量较CKU组分别降低8.34%、11.87%、14.08%、16.97%,11.94%、15.19%、18.21%、19.06%,7.40%、14.93%、19.47%、19.30%和6.84%、15.60%、22.39%、24.10%,RFV提高18.88%、26.20%、34.00%、37.88%。CaO与Ca（OH）₂碱贮效果相近,添加3%尿素碱贮较CaO或Ca（OH）₂直接碱贮效果更佳,且可长期保存。