Tropical fish medicine. Parasites associated with ornamental fish

The diagnosis, treatment, and control of parasites and nonparasitic pests of aquarium fish are covered. Figures are provided that should help the clinician make specific diagnoses.     

Vascular pattern of the developing intertarsal joint in the domestic fowl

The origin and nature of vascular canals in the distal tibiotarsus and proximal tarsometatarsus of the fowl have been described. The vascular pattern was modified at different stages of growth and there were anastomoses between epiphyseal vascular canals in the proximal tarsometatarsus. Such anastomoses are not seen in other bone extremities of the fowl and their presence may be a consequence of the incorporation of tarsal elements in proximal tarsometatarsi. In all the distal tibiotarsi examined, a third epiphyseal ossification centre was present. The pattern of metaphyseal vessels in the distal tibiotarsus and proximal tarsometatarsus was altered in some young chicks. This finding may be the result of abnormal angulation of the intertarsal joint which would result in uneven joint loading.     

Persistent pupillary membrane and congenital cataract in a litter of English cocker spaniels

In a litter of seven three-week-old English cocker spaniels, four showed persistent pupillary membrane and congenital cataract. One affected male and two affected females were kept for breeding purposes. Brother/sister mating gave birth to 14 pups. Two pups died the first day. The other 12 were euthanased at an age of one year. None of them showed any sign of eye diseases either by clinical or histological examination. The parents, one male and two females, were euthanased at the age of 20, 24 and 33 months, respectively. Clinical and histological examination of the eyes showed varying degree of loss of vision, persistent pupillary membranes, microphthalmos and cataract.     

A retrospective analysis of radiation therapy for the treatment of feline vaccine‐associated sarcoma*

We retrospectively evaluated predictive prognostic factors in 73 cats with vaccine‐associated sarcoma given postsurgical curative (n = 46, most with clean margins) or coarse fractionated radiotherapy (n = 27, most with either macroscopic disease or dirty margins). The former animals displayed a median survival of 43 months and a median progression free interval (PFI) of 37 months, the latter reached a median survival of 24 months and a median PFI of 10 months. In cats undergoing coarse fractionated therapy, factors predictive of a better outcome included lack of visible mass (n = 10) as opposed to macroscopic disease (n = 17, survival: 30 versus 7 months, P = 0.025; PFI: 20 versus 4 months, P = 0.01), adjuvant chemotherapy for gross disease (n = 5/17, survival: 29 versus 5 months, P = 0.04) and a smaller number of surgeries preceding radiation therapy (coeff = 0.41, P = 0.03). The Ki67 index was not predictive for survival. We concluded that postsurgical curative and coarse fractionated radiotherapy are effective legitimate options for managing vaccine‐associated sarcomas.     

Pelvic lymphoma as a cause of urethral compression in a mare

A 6-year-old mare was presented for evaluation of dysuria and pollakiuria. A pelvic mass, which caused obstruction of urinary outflow, was identified. Evidence of renal failure was also present. Due to poor prognosis the mare was euthanized. A postmortem examination revealed a pelvic lymphoma that surrounded and compressed the urethra.     

Factors affecting plasma prolactin concentrations throughout gestation in high producing dairy cows

The aim of the present study was to investigate possible relationships between plasma concentrations of prolactin and the following factors throughout gestation in lactating dairy cows: photoperiod, season, milk production, Neospora caninum-seropositivity, twin pregnancy, and plasma concentrations of pregnancy associated glycoproteins-1 (PAG-1), progesterone and cortisol. Pregnancy was diagnosed by trans-rectal ultrasonography on Day 40 post-insemination and by palpation per rectum on Days 90, 120, 150, 180 and 210 or until abortion in aborting cows. Blood samples were collected from each animal immediately before each pregnancy diagnosis. The study population was comprised of 73 non-aborting (54 Neospora-seropositive cows) and 20 aborting cows (all Neospora-seropositive) cows. In non-aborting cows, GLM repeated measures of analysis of variance revealed that lactation number and days in milk had no effect on plasma prolactin concentrations throughout gestation, whereas high plasma prolactin concentrations were significantly associated with high plasma levels of cortisol and PAG-1, with Neospora-seropositivity, positive photoperiod (increasing day length), twin pregnancy, and with low plasma progesterone concentrations. An interaction among plasma prolactin, plasma cortisol and milk production was observed in that plasma prolactin concentrations differed significantly throughout gestation and were highest in high-producing cows with high cortisol levels. In Neospora-seropositive non-aborting versus aborting cows, mean prolactin concentrations failed to differ on Days 40, 90, 120, 150 and 180 of pregnancy, whereas prolactin values were significantly lower (P = 0.03) in aborting animals on Day 210 of pregnancy. Our results indicate that a positive photoperiod and Neospora-infection lead to increased plasma prolactin concentrations throughout gestation. Reduced prolactin concentrations detected in Neospora-seropositive aborting cows compared to non-aborting animals suggests a protective effect of prolactin in N. caninum infection.     

The potential of replacing conventional dairy supplements with forage legume-based diets in Zimbabwe’s smallholder dairy sector

The effect of replacing commercial supplements with isoenergetic and isonitrogenous velvet bean-, cowpeaand lablab-based supplements on milk yield, milk quality and economic returns in smallholder crossbred dairy cows was investigated in the 2013 and 2014 dry seasons. Using 3 × 3 Latin square designs, nine multiparous Red Dane, Guernsey and Holstein-Friesian crosses in mid-lactation (130 ± 19 d) were offered forage legume-based supplements for 63 d at 0.5 kg per litre of milk produced. Milk quantity and quality were significantly (P < 0.05) different among supplements in both seasons. Cows fed commercial supplements had higher milk yield than cows fed forage legume supplements. Milk fat content was significantly (p < 0.05) higher in cows fed lablab-based supplements than cows fed other supplements. Milk protein, total solids and lactose content of cows fed commercial supplements was significantly (p < 0.05) higher than those fed forage legume-based supplements, although protein content was similar to cows fed lablab-based supplements. Dietary gross margins were higher for cows fed velvet beanand lablab-based supplements by 17% and 16.5%, respectively. Based on supplement, production costs per litre of milk was higher by 28% and 23% using commercial supplements compared to velvet bean and lablab supplements, respectively.     

Utilization of nitrogen and energy by Holstein steers fed formaldehyde- and formic acid-treated alfalfa or orchardgrass silage at two intakes

Our objective was to measure the utilization of energy (E) and N by Holstein steers when fed alfalfa and orchardgrass silages offered at 65 and 90 g DM/kg live weight (LW).75 daily. Twelve steers adapted to the Beltsville respiration chambers were assigned to three Latin squares with 42-d periods. Steers in one square had permanent catheters in the portal and two mesenteric veins. Energy and N balance were measured during a 7-d collection of feces and urine that included a 3-d measurement of respiratory exchange. Energy and N variables were not different between catheterized and uncatheterized steers. Apparent digestibilities of DM, OM, CP, neutral detergent solubles and permanganate lignin were higher (P less than .01) and digestibilities of NDF and ADF, hemicellulose and cellulose were lower (P less than .01) for steers consuming alfalfa compared to orchardgrass silage. When fed alfalfa, steers' daily gross energy intake, DE, urine energy, ME, heat production and tissue energy retention were greater (P less than .01) and fecal energy losses were less (P less than .01) than when they were fed orchardgrass. Partial efficiency of ME use for tissue energy (TE) was greater (P less than .01) for steers when fed alfalfa (46.1%) than when fed orchardgrass (35.6%). Apparent ME (kcal/LW.75) required for maintenance of TE was similar for steers when fed alfalfa (133.9) and orchardgrass (131.2) silages. Nitrogen retention (g/d) was 48% greater (P less than .01) for steers when fed alfalfa (30.6) than when fed orchardgrass (20.7). This study demonstrates that steers used ME from alfalfa more efficiently for TE deposition than ME from orchardgrass.