Partitioning nitrogen and amino acids for pregnancy and lactation in swine: a review

Nitrogen and amino acid requirements for maintenance, maternal growth, mammary growth and products of conception were partitioned on the basis of data from numerous sources. These data were compared with N retention values obtained from balance trials conducted during pregnancy. Carefully conducted N balance trials will yield N retention data that are reasonably comparable with N deposition data determined from tissue analyses. Based on indispensable amino acid (IAA) requirements for maintenance and pregnancy, the IAA were partitioned among maintenance, maternal growth, and products of conception including mammary growth. The nonspecific N requirement also was estimated in these calculations. Results indicate that the pregnancy requirements for total N and nonspecific N could be reduced considerably from present recommendations (NRC, 1988). Nitrogen and IAA requirements for lactation were partitioned between maintenance and milk production. Estimates of total N and nonspecific N that were derived factorially also were substantially less than present recommendations (NRC, 1988).     

Reconstruction of the parotid duct in a horse using an interposition polytetrafluoroethylene tube graft

A Thoroughbred gelding was referred for treatment of a parotid duct fistula. This had developed after the referring veterinarian had excised a portion of the duct, and ligated the proximal end, as a means of treating a recurring sialocoele. This report describes the successful surgical reconstruction of the excised 15 cm portion of the parotid duct using an interposition polytetrafluoroethylene tube graft.     

Phenylalanine requirement of the lactating sow

Six mature Yorkshire X Landrace sows were randomly assigned to a 6 X 6 Latin-square experiment on d 3 of lactation to determine the phenylalanine (Phe) requirement in the presence of excess tyrosine (Tyr). A control diet of corn sugar, cornstarch, whey, L-glutamic acid, solka floc, soybean oil, amino acids, minerals and vitamins was supplemented with L-Phe to provide .175, .250, .325, .400, .475 and .550% Phe and .47% Tyr. Each diet was fed to a maximum of 5.5 kg/d within each of six 7-d periods. Sow milk yield and average pig weight gain decreased (cubic, P less than .01) with increasing time period. Feed intake and average pig weight gain were depressed (quadratic, P less than .05) on the lowest Phe diet, but milk yield was not significantly affected. Daily nitrogen (N) intake was depressed (quadratic, P less than .01) when sows consumed the .175% Phe diet, but percent fecal N was not affected. Percent urine N decreased (quadratic, P less than .001) and percent N retained (without milk) increased with increasing Phe to .288 and .296%, respectively. Daily secretion of milk N as a percentage of N intake was not affected by diet. Percent overall N balance (with milk) increased with increasing Phe to .307%. Urea N decreased with increasing dietary Phe in both plasma (linear, P less than .01) and urine (quadratic, P less than .001) to a breakpoint at .285% Phe. A sharp rise (quadratic, P less than .01) in plasma Phe occurred at .299% dietary Phe. Plasma Tyr increased (quadratic, P less than .05) as dietary Phe increased, but no clear inflection point was obtained.(ABSTRACT TRUNCATED AT 250 WORDS)     

The efficacy of a controlled-release albendazole capsule in suppressing nematode burdens in sheep

An experiment was undertaken between July and November 1985 in East Gippsland, Victoria, to determine the efficacy of an intra-ruminal controlled-release albendazole capsule against naturally acquired worm burdens and larval challenge in Merino hoggets. Two groups of 20 sheep, one group untreated, the other dosed with a capsule were grazed together; 5 sheep from each group were slaughtered for total worm counts 30 and 101 d after capsules were administered. Serum anthelmintic concentrations, faecal egg counts and body weights were monitored. Most capsules were exhausted within 91 d of administration. During the estimated 80 d for which they remained active the capsules were highly effective against the benzimidazole-susceptible worm populations. Faecal egg counts were reduced to zero and total worm populations were reduced by over 97% 30 d after administration. By 101 d egg counts were increasing and worm counts indicated that sheep were becoming reinfected. Sheep treated with the capsules grew faster than those not treated.     

An evaluation of calf castration by intra-testicular injection of a lactic acid solution

This experiment evaluated intra-testicular injection of a sclerosing drug, lactic acid, for castration of bulls. Its use was compared in 58 Brahman cross calves (50 to 128kg) with the general practice of open surgical castration. Chemical castration appeared to be more painful than surgical castration, though post-operative swelling and pain appeared similar for both methods. Chemical castration took 3 times longer than surgical castration (58 sec v 20 sec; P less than 0.01). Scrotal necrosis occurred in 25% of chemically-castrated calves and appeared due to drug leakage from the testes under the high pressure of injection. Healing time for chemical castrates was approximately twice that for surgical castrates. Five chemically-castrated calves (18%) retained one testis. Though all 5 were rendered sterile, each maintained androgenesis. This led to secondary male behaviour which caused management problems. Castration method did not influence post-operative growth. It is concluded that lactic acid administration is not a suitable alternative to the open surgical technique for castration of Brahman cross calves.     

Management of equine skull fractures using fixation with polydioxanone sutures

Ten horses presented with severe distortion of the facial contour, crepitus on palpation and mild to moderate epistaxis. Individual horses also showed ocular damage, ptosis, severe dyspnoea and movement of the facial bones concurrent with respiration. The fracture fragments were exposed using a large curvilinear incision and elevated using a retractor, periosteal elevator, chisel or Steinmann pin. The fracture fragments were unstable following reduction and fixation was necessary. Stabilisation was achieved with polydioxanone sutures placed through holes drilled in opposing sides of the fracture lines. Polydioxanone sutures provided good stability and had better handling properties than wire. There was good apposition of fracture edges and minimal complications. Use of polydioxanone sutures can also avoid the expense and complexity of plate fixation in selected cases, and should be considered as an alternative to fixation with stainless steel wire in any facial fracture that adjoins stable bone.