Performance of broiler chicks fed on alkali‐treated neem (Azadirachta indica) kernel cake as a protein supplement

1. An experiment was conducted to evaluate growth and nutrient efficiency of broiler chicks from 3 to 42 d fed on diets containing alkali‐treated neem (Azadirachta indica A. juss) kernel cake (NKC) as a protein supplement in place of peanut meal (PNM).

2. NKC was treated with sodium hydroxide at 10 (ANKC 1) or 20 g (ANKC 2)/kg and incorporated into the test diets at 135 or 300 g/kg to replace 50 (low—L) or 100 (High—H) % of the PNM protein of the reference diet.

3. Despite comparable retentions of dry matter and total carbohydrate on L‐ANKC 1 and 2, fibre on L‐and H‐ANKC 2 and nitrogen, calcium and acid detergent fibre on all experimental diets compared to the retentions of chicks on the reference diet, only the chicks fed L‐ANKG 2 were found to grow and utilise food as well as those on the reference diet.

4. The activities of serum alkaline phosphatase on H‐ANKC 1 and alanine amino transferase on all test diets were depressed (P < 0.05), but the activity of serum aspartate amino transferase, total erythrocyte count and concentration of blood haemoglobin and urea were similar in all chicks.

5. No significant differences were noticed in the qualitative and quantitative characteristics of the meat of chicks fed on the reference diet and on diets incorporating ANKC at the lower concentrations. Feeding ANKC protein did not impart any untoward taste as evaluated in pressure cooked meat by a semitrained panel on a 7 point Hedonic scale.

6. Except for duodenal and jejunal inflammation in chicks on both reference and test diets, all the vital organs were normal, ruling out any adverse affects caused by residual neem bitters.

7. Comparable performance and cost of chicks fed on the reference and L‐ANKC 2 diets, warrants the utilisation of hitherto wasted protein‐rich NKC after alkali treatment in broiler chick diets to spare peanut meal for human consumption in developing countries.     

A formation mechanism for catalytically grown helix-shaped graphite nanotubes

The concept of a spatial-velocity hodograph is introduced to describe quantitatively the extrusion of a carbon tubule from a catalytic particle. The conditions under which a continuous tubular surface can be generated are discussed in terms of this hodograph, the shape of which determines the geometry of the initial nanotube. The model is consistent with all observed tubular shapes and explains why the formation process induces stresses that may lead to "spontaneous" plastic deformation of the tubule. This result is due to the violation of the continuity condition, that is, to the mismatch between the extrusion velocity by the catalytic particle, required to generate a continuous tubular surface, and the rate of carbon deposition.     

Additive genetic and maternal effects on postweaning growth and carcass traits in rabbits

SUMMARY: Additive genetic and maternal effects were estimated for postweaning growth traits and carcass traits using a derivate-free REML procedure under animal model. The traits studied were weight at 84 days of age, age at slaughter, postweaning ADG, dressing percentage, weight of kidney and pelvic fat, and muscle pH value and electrical conductivity in the semimembranosus muscle. Heritability estimates from a total of 728 rabbits in a reciprocal crossbreeding experiment ranged from 0.15 to 0.26 for postweaning growth traits, 0.21 for dressing percentage, 0.38 for weight of kidney and pelvic fat, 0.02 for pH value, and 0.51 for electrical conductivity. Considerable maternal effects were present in postweaning growth traits and in weight of kidney and pelvic fat. Genetic correlation estimates indicated that genetic selection for postweaning daily gain would lead to lower dressing percentages (- 0.51) and leaner carcasses (- 0.34). The genetic relationships between ADG after weaning and pH value (- 0.90), and between ADG and electrical conductivity (0.58) illustrated a shifting towards a glycolytic energy metabolism of the muscle due to increased growth. Litter size at birth was found to be a significant source of variation for all postweaning growth traits (p < 0.001) and for electrical conductivity (p < 0.05). Genetic selection for litter size at birth would result in decreased growth rates, lower dressing percentage and enhanced adiposis. ZUSAMMENFASSUNG: Die Sch?tzung additiv-genetischer und maternaler Effekte auf Mastleistungs- und Schlachtk?rpermerkmale beim Kaninchen Additiv-genetische und maternale Effekte wurden für Mastleistungsmerkmale nach dem Absetzen und für Schlachtk?rpermerkmale anhand eines Tiermodells (DFREML-Methode) gesch?tzt. Bei den untersuchten Merkmalen handelt es sich um das 84-Tage-Gewicht, das Schlachtalter, Zunahmen nach dem Absetzen, Ausschlachtungsprozente, Nieren- und Beckenfettgewicht und um den pH-Wert und die elektrische Leitf?higkeit im M. semimembranosus. Die Heritabilit?tssch?tzungen an insgesamt 728 Tieren, die aus einem reziproken Kreuzungsversuch stammten, lagen bei den Wachstumsmerkmalen zwischen h(2) = 0,15 und h(2) = 0,26. Sie betrugen h(2) = 0,21 für die Ausschlachtungsprozente, h(2) = 0,38 für das Nieren- und Beckenfettgewicht, h(2) = 0,02 für den pH-Wert und h(2) = 0,51 für die Leitf?higkeitsmessung. Die Sch?tzung genetischer Korrelationen deutet an, da? eine genetische Selektion auf t?gliche Zunahmen nach dem Absetzen zu einer verringerten Ausschlachtung (- 0,51) und zu magereren Schlachtk?rpern führen würde. Die genetischen Beziehungen zwischen den Zunahmen und dem pH-Wert (- 0,90) und zwischen den Zunahmen und der elektrischen Leitf?higkeit (0,58) lassen eine Verschiebung in Richtung eines glykolytischen Muskelenergiestoffwechsels bei verst?rktem Wachstum erwarten. Die Wurfgr??e bei der Geburt stellt eine signifikante Variationsursache für die Mastleistungsmerkmale nach dem Absetzen (p < 0,001) una für die elektrische Leitf?higkeit (p < 0,05) dar. Bei einer Erh?hung der Wurfgr??e durch Selektion sind verminderte Wachstumsraten, geringere Ausschlachtungsprozente und verst?rkte Verfettung zu befürchten.     

Correct equations for comparing models in diallel analysis

SUMMARY: Correct equations are given to express the parameter estimates of four models for complete diallels as a function of the parameter estimates in the model of Eisen et al. (1983). In recent literature these equations have been partly incorrect. ZUSAMMENFASSUNG: Korrekte Gleichungen für den Vergleich von Modellen in der Diallelanalyse Für die Darstellung der Parametersch?tzwerte von vier Modellen für vollst?ndige Diallele als Funktion der Parametersch?tzwerte des Modells von Eisen et al. (1983), die in der Literatur teilweise fehlerhaft erfolgte, werden korrekte Formeln angegeben.