A comparison of different drying techniques for energy and amino acid analyses of poultry excreta

1. Broilers were fed on wheat‐casein or wheat‐soyabean meal diets and the excreta collected after 12 and 24 h. Samples of excreta were freeze dried or dried in a force draught oven at 60 or 80 °C.

2. Drying procedure and collection time significantly influenced the determined energy and nitrogen concentrations of the excreta.

3. Drying excreta in an oven at 60 °G proved at least as effective as freeze drying for the majority of amino acids.     

Depression of polymorphonuclear leukocyte function associated with experimentally induced Escherichia coli mastitis in sows

In a study of susceptibilities of sows from 2 herds to experimentally induced Escherichia coli mastitis, a marked difference was seen. The "susceptible" sows were from a conventional herd and "resistant" sows were from a specific-pathogen-free herd. The purpose of the study was to determine whether deficient neutrophil function was associated with increased susceptibility to E coli-induced mastitis. Four in vitro procedures were used to evaluate polymorphonuclear leukocyte (PMN) function: (i) random migration under agarose, (ii) ingestion of 125I-iododeoxyuridine-labeled Staphylococcus aureus, (iii) quantitative nitroblue tetrazolium reduction, and (iv) iodination. After parturition and intramammary inoculation with E coli, sows from the susceptible herd were neutropenic and the neutrophils which were present in the peripheral blood had reduced function. Specifically, there were depressed random migration under agarose, S aureus ingestion, and iodination when compared with PMN function in resistant sows. These data indicate that susceptibility to E coli mastitis was associated with deficiencies in PMN numbers and function. Potential causes of the neutrophil dysfunction are discussed and include possible systemic hormonal aberrations or the presence of an inapparent viral or bacterial infection.     

A 31P topical magnetic resonance study of embryonic development in hens' eggs

1. A ³¹P topical magnetic resonance study of whole chicken's eggs in vivo is described.

2. Resonances from adenosine triphosphate, phosphocreatine, inorganic phosphate and phosphorous storage protein were observed. These changed in relative intensity as the embryo developed.

3. No ill effects due to exposure to radiofrequency radiation or magnetic fields were observed.

4. It is concluded that topical magnetic resonance can make a useful contribution to the study of embryonic development in avian eggs.     

Effects of lauryl sulphate on egg‐shell quality in laying hens

1. The effect of feeding the detergent, sodium lauryl sulphate at concentrations up to 10 g/kg diet on egg‐shell quality was examined in laying hens at 24, 36 and 48 weeks of age.

2. Lauryl sulphate at 2.5 g/kg or more in the diet significantly increased shell breaking strength, shell thickness and shell weight at 24 and 36 weeks. In 48‐week‐old hens only shell breaking strength was increased significantly. Egg production and egg weight were not affected significantly by lauryl sulphate.

3. Lauryl sulphate might increase these measures of quality by increasing shell deposition and/or shell elasticity.     

Observations on an outbreak of foot abscess in sheep

An outbreak of ovine interdigital dermatitis and foot abscess in which approximately a third of 300 Perendale ram hoggets had acute lameness was investigated. Both foot infections occurred simultaneously in the flock, and ovine interdigital dermatitis preceded the occurrence of foot abscess in seven instances. It was suggested that the behaviour pattern and sexual activity of the young rams predisposed them to ovine interdigital dermatitis and foot abscess. Although no controlled trials were conducted, the lame sheep responded well following the combined therapeutic measures of dry surroundings, formalin footbathing and selected antibiotic therapy.