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Parafilaroides decorus, also known as sea lion lungworm, is a metastrongyloid nematode that infects otariid hosts, such as the charismatic California sea lion, Zalophus californianus. P. decorus causes bronchointerstitial pneumonia, respiratory distress, reduced ability to swim, dive and hunt and as a result, increased mortality particularly in young animals. Respiratory disease is a leading cause of stranding and admission to rehabilitation centers on the Pacific coast. Low-coverage genomic sequencing of four P. decorus individuals analyzed through Galaxy's RepeatExplorer identified a novel repeat DNA family we employed to design a sensitive quantitative PCR (qPCR) assay for diagnosing infections from fecal or sputum samples. The assay detects as little as 10 fg of P. decorus DNA and a linear regression model developed using a standard curve can be used to estimate the concentration of P. decorus DNA in a sample, ± 0.015 ng. This knowledge can be leveraged to estimate the level of parasite burden, which can be used to design improved treatments for animals in rehabilitation. Improved treatment of infections will aid in more animals being successfully released back into the wild., Graphical abstract Image 1, Highlights • Developed qPCR assay for P. decorus. • Sensitive to 10 fg. • Applicable for feces or sputum.

An improved method for the separation and isolation of urea N and glutamine amide N for 15 N metabolic studies has been developed. This procedure overcomes the problem of alkaline hydrolysis of glutamine amide N encountered in the other methods available. Data are presented which indicate that urea N and glutamine amide N can be separated by this procedure with a minimal isotopic mixing or contamination. Procedures are suggested for application of this method for 15 N studies in both blood and tissue samples.

1. 1. Intraperitoneal LD 50 and LD 99·9 values for ammonium acetate were determined in three species of ammonotelic fishes; rainbow trout ( Salmo gairdnerii ), channel catfish ( Ictalurus punctatus ) and goldfish ( Carassius auratus ). 2. 2. There was a direct relationship between the LD 50 values for ammonium acetate and the relative resistance to environmental conditions, i.e. the trout were the most sensitive, the channel catfish intermediate and the goldfish quite resistant. 3. 3. An increase in aquarium temperature considerably decreased the fishes tolerance to the injected ammonium acetate. 4. 4. Fishes being ammonotelic were found to be more tolerant to the intraperitoneally administered ammonium acetate than either the ureotelic or uricotelic species (Wilson et al. , 1968). 5. 5. Several factors which may contribute to the higher tolerance of exogenous ammonia in the fishes are discussed.

1. 1. Intravenous and intraperitoneal ld 50 and ld 99·9 values for ammonium acetate were determined in a uricotelic species ( Gallus domesticus ) and in a ureotelic species ( Mus musculus ). 2. 2. The intravenous ld 50 and ld 99·9 values were 2·72 ± 0·101 and 4·87 ± 0·101 m-mole/kg body weight for chicks and 5·64 ± 0·083 and 7·67 ± 0·083 m-mole/kg body weight for mice. 3. 3. The intraperitoneal ld 50 and ld 99·9 values were 10·44 ± 0·405 and 26·2 ± 0·405 m-mole/kg body weight for chicks and 10·84 ± 0·203 and 18·0 ± 0·203 m-mole/kg body weight for mice. 4. 4. Intravenously, the ammonium acetate was twice as toxic in the chick as in the mouse, indicating in the chick a critical organ more sensitive to the ammonium ion. 5. 5. Intraperitoneally, the ammonium acetate did not differ significantly in tolerance by mice and chicks, indicating that in the avian liver some other pathway may be as efficient for detoxifing exogenous ammonia as the urea cycle in the mouse liver.

Various substrates for urea and uric acid synthesis were studied for their effects against acute ammonia intoxication in chicks. Glycine and glucose + glycine were shown to exert a significant protective effect against ammonia intoxication in chicks with no comparable effect in mice. The urea cycle substrates showed no protective effects in the chicks. It is suggested that glycine and glucose are the limiting substrates for purine synthesis in chicks under an ammonia stress. Evidence is presented that indicates that glucose + glycine exerts its effect by enhancing uric acid synthesis.

1. 1. The possible protective effect of some sodium salts of metabolizable acids against ammonia intoxication in chicks (Gallus domesticus) has been investigated. 2. 2. The following compounds were shown to exert a significant protective effect against ammonia intoxication in the chick when administered intraperitoneally 1 hr prior to the ammonia challenge: 2, 3 and 4 m-moles/kg sodium acetate; 3 m-moles/kg sodium propionate; 3 m-moles/kg sodium butyrate; 3 m-moles/kg sodium bicarbonate; and 3 m-moles/kg potassium acetate. These compounds did not have a comparable effect in mice (Mus musculus). 3. 3. Evidence is presented which indicates that the sodium ion of the metabolizable sodium salts exerts its effect by enhancing uric acid transport or excretion.