Development of the lipid and fatty acid patterns of the liver of the pigeon after hatching

1. The fatty liver of newly‐hatched pigeons is caused by an accumulation of sterol esters (STE) amounting to 620 mg/g total lipids of which 80% was sterol oleate. Triglycerides (TG) accounted for only 20 mg/g of total lipids.

2. After hatching, the relative amount of STE in the liver tissue decreased considerably while that of TG increased. The proportion of phospholipids (PHL) remained essentially constant.

3. The fatty acid composition of the liver lipids changed significantly, but specifically for each individual class during postnatal growth. Striking differences were the higher values of long‐chain polyunsaturated acids (20 :4 ω6, 22 :4 ω6 and 22: 6 ω3) in PHL, TG and free fatty acids (FFA) and the higher proportion of oleic acid in the STE at hatching compared with those at older ages.

4. The predominant alterations in the relative composition of the liver lipids (lipid classes and fatty acids) occurred in the first week after hatching and may be accounted for by the decreasing yolk utilisation and adaptation to ingested food. The change within the diet itself from cropmilk to grain (starting around the 4th day) influenced the development of the lipid and fatty acid content only in a minor way.

5. The large weight decrease of the pigeon liver after the 19th day was accompanied by a decrease in absolute PHL content while TG stores were unaltered.     

Concentrations of plasma luteinising hormone,prolactin, progesterone and androgens during the ovulatory cycle of the Turkey

1. Changes in the concentrations of plasma luteinising hormone (LH), prolactin, androgen and progesterone were measured during the ovulatory cycle of the turkey.

2. Single pre‐ovulatory peaks of plasma LH, androgen and progesterone were observed which took 8, 8 and 12 h respectively, to increase and return to base‐line values. The concentration of plasma prolactin tended to be elevated between 6 h before and 6 h after the LH peak with the maximum values occurring after the peak.

3. The changes in the concentrations of plasma LH and progesterone were 3‐ and 7‐fold respectively while 2‐fold changes were observed in the concentrations of plasma androgen and prolactin.

4. The pre‐ovulatory concentration of plasma progesterone and prolactin began to decrease 4 and 6 h respectively, after the pre‐ovulatory peak of LH.

5. Ovulation and oviposition occurred 6 to 8 h and 36.10+ 0.57 h (SEM) ( n= 11) respectively after the pre‐ovulatory peak of LH.

6. In birds kept on 14 h light/d, pre‐ovulatory peaks of LH were initiated only during a 10 to 11‐h period starting within 2 h after the onset of darkness.

7. A comparison between these data and those from the fowl suggest that the egg is retained in the turkey's oviduct for about 3 to 4 h longer than in the fowl.     

Preservation of fowl semen in liquid nitrogen: Application to breeding programmes

1. A method of freezing semen of individual males was adapted for use under farm conditions using an automated freezing apparatus.

2. An insemination programme to produce high fertility and hatchability with semen which had been deep frozen for 2 months was devised.

3. Over 90% fertile eggs with a 90% hatch of all eggs set was obtained with frozen and thawed semen over a period from the 2nd to the 12th day after the first of four inseminations. The persistency of fertility was also tested and 93, 86.6 and 30.7% of the eggs were fertile during days 2 to 6, 2 to 8 and 9 to 15 after the last insemination.

4. Corresponding with the high fertility rate, chicks were produced by every hen that was inseminated and from every male whose semen was frozen and stored. The implications for future breeding practices of this successful result are discussed.     

Neuromusgular studies of turkeys with trienbolone acetate‐induced and naturally occurring “leg weakness”

1. In vivo sciatic nerve gastrocnemius muscle preparations were made from 14‐ to 18‐week‐old normal turkeys and from those with naturally occurring or trienbolone acetate (TA)‐induced “leg weakness”.

2. Preparations from leg weakness cases displayed neither accelerated muscle fatigue nor decreased nerve conduction velocities as compared with control preparations.

3. The muscles of the TA‐treated turkeys but not of those with naturally occurring leg weakness were hyperexcitable relative to those of controls.

4. Post‐tetanic potentiation of preparations from both naturally occurring and experimentally‐induced cases of leg weakness was less than that of control preparations, both before and after partial neuromuscular blockade, significantly so at the lower pulse frequencies used.

5. It is tentatively suggested that the last finding might be of significance in explaining the clinical signs of leg weakness and might be associated with a disordered calcium metabolism.     

Incubation of chicken eggs at altitude theoretical consideration of optimal gas composition

1. Eggs from sea level which are transferred to higher altitude for incubation require changes in incubator gas composition if they are to develop normally.

2. This not only requires compensation for the reduced O₂ partial pressure but, and of equal importance, recognition of the increased diffusivity of gases at altitude.

3. Equations are developed for predicting the required changes in O₂, CO₂ and water vapour composition of incubator gas at any altitude.     

Effects of high inclusion rates of salseed meal in the diet of chicks

1. Starter diets containing either maize or salseed meal to replace the maize were fed to chicks over a period of 2 weeks.

2. Growth rate, food intake, food utilisation and proportion of dietary nitrogen retained were much poorer in chicks receiving salseed meal.

3. The chicks receiving salseed meal developed pathological lesions in liver and kidney.

4. The red blood cell count, white blood cell count, haemoglobin concentration and packed cell volume of the chicks receiving salseed meal were lower than those of chicks receiving maize.

5. The apparent metabolisable energy value of salseed meal was determined as 6.83 MJ/kg.     

Archeological evidence for pimple (pralrie) mound genesis

Archeological deposits have been discovered in three pimple mounds on the upper Texas coast. Such incorporation indicates that (i) these particular mounds are aggradational rather than erosional in origin; (ii) mound formation continued until at least A.D. 1100 to 1200; (iii) each mound took 300 to 500 years to form; (iv) mounds within the same mound field did not form simultaneously; (v) certain Gulf Coast pimple mounds have archeological research potential; and (vi) archeological data also offer a means for investigating mound formation.