Differences in Growth in Blue Catfish Ictalurus furcatus and Channel Catfish Z. punctatus Fed Low-Protein Diets With and Without Supplemental Methionine and/or Lysine

Three feeding experiments were conducted to evaluate growth and body composition in blue caffish Ictalurus furcatus or channel caffish I. punctatus when fed diets containing 22% protein with or without supplemented methionine and/or lysine. All experiments were conducted in 110‐L aquaria that were part of a recirculating system. In Experiment 1,15 juvenile blue catfish (2.7 g) were randomly stocked into aquaria and fed one of three diets containing different (22%, 27%, and 32%) percentages of protein. Fish were fed twice daily to excess for 10 wk. In Experiment 2, juvenile blue catfish (5.4 g) were randomly stocked into aquaria and fed one of six diets containing either 22% (diet 1) or 32% (diet 2) protein. The diet containing 22% protein (diet 1) had either 0.3% crystalline L‐methionine (diet 3), 0.4% crystalline L‐lysine (diet 4), or 0.3% L‐methionine + 0.4% L‐lysine (diet 5) added. A sixth diet was formulated to contain 32% protein and 0.2% crystalline L‐methionine. Fish were fed in excess for 12 wk. In Experiment 3, juvenile channel caffish (10.3 g) were stocked and fed diets 14 from Experiment 2, twice daily in excess for 8 wk. In Experiment 1, after 10 wk, final individual weight, weight gain (%), and specific growth rate (SGR) of blue catfish fed diets containing three protein levels were not significantly different (P > 0.05) and averaged 12.9 g, 378%, and 2.2%/d, respectively. Fish fed the diet containing 27% protein had higher (P < 0.05) whole‐body protein (65.4%) compared to fish fed diets containing either 22% or 32% protein. In Experiment 2, final weight, weight gain (%) and SGR of blue catfish were not significantly (P > 0.05) different among diets and averaged 24.7 g, 355%, and 1.8%/d, respectively. Percentage whole‐body protein and lipid were not significantly (P > 0.05) different between fish fed diets containing 22% or 32% protein. In Experiment 3, channel caffish fed a diet containing 32% protein had significantly (P > 0.05) higher final individual weight, weight gain (%), and SGR compared to fish fed diets containing 22% protein, with and without supplemental methionine or lysine. Results indicate that blue catfish may be able to utilize a diet with 22% protein, and that addition of crystalline methionine and/or lysine did not improve growth. However, channel catfish grown in aquaria did not appear to have similar growth when fed a diet containing 22% protein compared to fish fed 32% protein, even when supplemental methionine or lysine was added. Further research on blue catfish and the use of a low‐protein diet (22% protein) needs to be conducted in ponds.     

A novel surgical treatment of type 3 congenital elbow luxation in a dog

Congenital luxation of the ulnar and radius is a rare orthopaedic condition in the dog. This case report describes a novel surgical treatment for congenital elbow luxation in a medium-breed dog. A 6-week-old Kelpie presented for left forelimb lameness and deformity. Radiographs and computed tomography (CT) confirmed the diagnosis of unilateral ulnar and radius luxation. The surgical repair involved open reduction followed by fixation with an extraarticular pin and a transarticular external fixator. The outcome of surgery was improved leg function and weight-bearing, however, reluxation of the radial head was diagnosed 7 weeks following surgery. This technique may offer an alternative surgical option to improve clinical signs, as well as insight into improving the management of this condition.     

Herd health planning: farmers' perceptions in relation to lameness and mastitis

Between December 2002 and December 2003, the herd health planning activities on 61 dairy farms in the uk were compared with several measures of lameness and mastitis. Lameness had been reported as a problem in 53 of the herds directly by the farm and in the other eight by the nominating local veterinary practice; 54 of the farms also reported having a mastitis problem. Fifty-three (87 per cent) of the farms had some form of written herd health plan, of which 21 (40 per cent) had been in place for 12 months or less. All the farms were recording mastitis in some way, although 38 (62 per cent) of the farmers did not review these records and only four retained the results of a comprehensive record review. Farms defined as having a high incidence of mastitis were more likely to be reviewing their health records, but farms defined as having a high prevalence of lameness in a sentinel group of early lactation heifers were less likely to be reviewing their health records.     

Black cohosh (Actaea racemosa, Cimicifuga racemosa) behaves as a mixed competitive ligand and partial agonist at the human mu opiate receptor

Black cohosh is a commonly used botanical dietary supplement for the treatment of climacteric complaints. Because the opiate system in the brain is intimately associated with mood, temperature, and sex hormonal levels, the activity of black cohosh extracts at the human mu opiate receptor (hMOR) expressed in Chinese hamster ovary cells was investigated. The 100% methanol, 75% ethanol, and 40% 2-propanol extracts of black cohosh effectively displaced the specific binding of [3H]DAMGO to hMOR. Further studies of the clinically used ethanol extract indicated that black cohosh acted as a mixed competitive ligand, displacing 77 +/- 4% [3H]DAMGO to hMOR (Ki = 62.9 microg/mL). Using the [35S]GTPgammaS assay, the action of black cohosh was found to be consistent with an agonist, with an EC50 of 68.8 +/- 7.7 microg/mL. These results demonstrate for the first time that black cohosh contains active principle(s) that activate hMOR, supporting its beneficial role in alleviating menopausal symptoms.     

Season and physiological status affects the circadian body temperature rhythm of dairy cows

The circadian body (vaginal) temperature rhythm was measured in 36 dairy cows: Holstein–Friesian (HF, n = 12), Jersey (J, n = 12) and their crossbreed, Holstein–Friesian × Jersey (HF × J, n = 12) at six different periods (5-7 days in duration) during the year that could potentially be a seasonal and physiological stressor. These were a) early winter (late pregnancy), (b) early spring (early lactation), (c) late spring (before mating at mid-lactation), (d) early summer (after mating at mid-lactation), (e) late summer (late lactation, early pregnancy) and, (f) early autumn (drying-off at the end of lactation, mid-pregnancy). Live weight and body condition score was recorded on the first day of each measurement period. Live weight differed (P < 0.001) with breed with HF cows heaviest and J cows lightest (HF: 525 ± 51, HF × J: 456 ± 56, J: 401 ± 30 kg). HF cows tended (P = 0.099) to have a higher body condition than either J or HF × J cows although the overall change in body condition during the experiment was similar (P = 0.961) amongst breeds. The circadian body temperature rhythm differed markedly between each measurement period, being flatter and having a less prominent morning nadir and afternoon peak during early winter compared to spring and summer. The timing of peak body temperature was 4-5 h earlier in early autumn in HF and HF × J cows relative to J cows. There was no breed difference (P ≥ 0.162) in daily mean body temperature except for a tendency (P = 0.075) for mean body temperature to be moderately higher in J cows (38.5 °C) during late summer compared to HF and HF × J cows (38.4 °C), primarily due to an increase (P = 0.001) in daily minimum body temperature (38.0 vs. 37.8 °C). The daily range of oscillation (maximum–minimum) in the body temperature rhythm was highest during late summer, particularly in HF and HF × J cows. Minimum body temperature was also higher (P = 0.033) for J cows than HF and HF × J cows during early autumn (37.9 vs. 37.8 °C). In conclusion, season and physiological status of cattle had a profound effect on the circadian body temperature rhythm but there was little difference between the breeds of dairy cows studied.