Rapeseed meal and egg taint: Treatment of rapeseed meal to reduce tainting potential

1. Treatment of rapeseed meal with calcium hydroxide suspension decreased the sinapine content by up to 90%. Smaller decreases were obtained by autolysis, steaming and treatment with ammonia.

2. When this treated meal was fed to susceptible ("tainting") hens the concentration of trimethylamine in the eggs was decreased to much less than that required to cause taint.     

The effects of meal feeding of calcium,protein and energy on production and calcium status of laying hens

1. Laying birds were allowed free access to a basal diet (treatment 1) or were restricted to either early morning and late afternoon access to the basal diet (treatment 2) or a high‐energy diet in the morning and a high‐protein, high‐calcium diet in the afternoon (treatment 3). The sum of the components fed in treatment 3 was equivalent to the basal diet. These diets were fed for 5 weeks. In the next phase of the experiment, which lasted for 3 weeks, the compositions of the diets for treatments 2 and 3 were altered so that the intakes of dietary components approached those of birds on treatment 1.

2. In both experimental phases birds on treatment 3 produced significantly fewer eggs of smaller mean weight and shell weight. Plasma calcium, inorganic phosphorus concentrations and alkaline phosphatase activity were indicative of decreased calcium status.     

The spoilage flora and shelf‐life of duck carcasses stored at 2 or ‐ 1°c in oxygen‐permeable or oxygen‐impermeable film

1. A comparison was made of” oven ready “ duck carcasses stored at 2 or — 1 °C and wrapped in either a low‐density oxygen‐permeable polyethylene film or a heat‐shrunk oxygen‐impermeable film.

2. At spoilage the main organisms at 2 and — 1 °C on the carcasses wrapped in the oxygen‐permeable film were pseudomonads, producing unacceptable “off odours” when their numbers were >10⁸/cm². This occurred in about 10 d at 2 °C but in about 19 d at ‐ 1° C.

3. The effect of wrapping in the heat‐shrunk oxygen‐impermeable film was to delay or inhibit the growth of pseudomonads and thus extend the shelf‐life by more than 50% at either temperature. The predominant organisms isolated from the spoiling carcasses were atypical lactobacilli and enterobacteria.

4. Sensory assessment of the carcasses stored at — 1 °C by a trained panel indicated that, although less obvious “ off odours “ were produced by the micro‐organisms growing on the carcasses wrapped in the impermeable film, differences were detected at 33 d when the numbers of bacteria reached about 10⁷/cm² whilst at 41 d the meat was described as rancid.     

Metabolic and anatomical adaptations of light‐bodied chicks to intermittent feeding

1. Chicks of a light‐bodied strain were deprived of food on alternate days from 15 to 46 d of age.

2. Hyperphagia, amounting to twice the intake of control birds early in the experiment, occurred on the repletion day.

3. Final body weight attained 80% of that of the controls.

4. Body fat concentration decreased at first but returned to that of controls after 3 weeks.

5. A consistent hyperlipaemia was observed after food deprivation or restoration.

6. There was a marked increase in the digestive enzymes found in the small intestine, but not in the pancreas during the repletion day.

7. These responses may be considered as mechanisms to reduce the physiological manifestations of starvation.     

Selection for food conversion in broilers: Direct and correlated responses to selection for body‐weight gain,food consumption and food conversion ratio

1. Direct and correlated responses were determined after five generations in four lines of chickens selected either for increased body‐weight gain (line W), for increased food consumption (line F), for decreased food conversion ratio (line E), or at random (line C).

2. Realised heritability estimates calculated after five generations of selection were : 0–37 + 0.04 for weight gain (WG); 0.44 + 0.05 for food consumption (FC); 0.21 + 0.04 for food conversion ratio (FCR).

3. Realised genetic correlation estimates were: WG and FC, +0.71 ±006; WG and FCR, ‐0.40±0.09; FC and FCR, +0.27 + 0.09.

4. Zero‐generation heritability and genetic correlation estimates were greater than the realised estimates, and sex linkage appeared to be important in the expression of all three traits.

5. The genetic correlation between FC and FCR was asymmetrical with considerable positive response in FCR in line F (r_g = +0.79) but negligible response in FC in line E (r_g = —0.01).

6. There was an apparent plateau in response in FCR in line E from the third to the fifth selected generations.     

The hen's egg: Evidence on the mechanism relating shell strength to loading rate

1. The decrease in strength of an egg shell which is known to accompany an increase in the period of time over which a load is applied might come about by either of two mechanisms: a decrease in the strength of the material constituting the strong, outer layer of the mineral shell, or a decrease in the thickness of this layer brought about by deepening of the crevices that are normally present between adjacent crystal columns in the weak, inner layer of the shell.

2. Experiments designed to discriminate between these mechanisms are described: the results indicate the second mechanism.

3. This mechanism offers explanations for various other shell phenomena, including delayed fracture under a static, cyclical or recurrent load.

4. The main implication for the poultry industry is that any external insult to a shell is likely to weaken it by doing damage that is local, internal, irreparable and cumulative, even though it may be invisible from the outside.     

Mucopolysaccharidosis in a domestic short-haired cat--a disease distinct from that seen in the Siamese cat.

A 10-month-old male domestic short-haired cat was examined because of progressive lameness, a broad face with depressed nasal bridge, small ears, corneal clouding, and multiple bone dysplasia. The cat excreted excessive amounts of glycosaminoglycan (a component of connective tissue) in its urine and had evidence of lysosomal storage of glycosaminoglycans in fibroblasts and neurons. Activity of alpha-L-iduronidase, a lysosomal enzyme involved in glycosaminoglycan degradation, was deficient in cultured fibroblasts and leukocytes. The mucopolysaccharidosis was distinct from that seen in Siamese cats in terms of the pathologic changes and the specific enzyme deficiency.     

Isolation of picornavirus from feces and semen from an infertile bull.

Virus was isolated from semen and fecal samples from a bull with orchitis, testicular degeneration, aspermatogenesis, and loss of libido. Both isolates were classified as picornavirus, bovine enterovirus serotype I, on the basis of physical, chemical, and serologic characteristics. Veterinary practitioners that may suspect viral infection as a cause of bovine infertility should submit both semen and fecal samples for virus isolation and identification.     

AN OESOPHAGEAL DIVERTICULUM IN A DOG

An 11-month-old male Miniature Poodle was found to regurgitate small volumes of fluid and food particles due to a diverticulum in the thoracic oesophagus. The diverticulum was removed surgically. Histologically the wall contained extensive scar tissue. Longterm recovery was uneventful and 5 months after surgery the dog is in good health     

Enzyme arrangement of various tissues in swine. 1. Studies of the effect of 32 hours of fasting, administration of actinomycin D, and fasting in combination with administration of actinomycin D on crude protein level, activities of GOT, GTP, fructose-1,6-diphoaphatase as well as ATPase of liver, kidneys and semitendinous muscle in newborn piglets]

The effects of sufficient milk intake as well as of 32 hours of fasting after birth, administration of actinomycin D (intraperitoneal application of 1 mg/kg five weight), and fasting in combination with actinomycin D on the development of body and liver weights, crude protein levels in homogenate and supernatant of liver, kidneys, and M. semitendinosus as well as on the activities of certain tissue enzymes were analysed with four groups of piglets (n = 4). Fasting, administration of actinomycin, and fasting in combination with actinomycin D resulted in rapid reduction in body and liver weights, while the crude protein levels in those tissues were not affected with significance. GOT and fructose-1,6-diphosphatase activities in supernatant from liver tended to decline under fasting conditions. The ATPase activity in the homogenate of the above tissues did not change in response to differentiated treatment.