Effects of Loose Housing Designs on Expressions of Milking Parlour Behaviours and Milk Yield of Crossbred Jersey Cows

Milking behaviour of dairy cows has serious impacts on their production efficiency. A number of genetic and environmental factors controls and influences milking behaviour of dairy cow. The aim of present study was to investigate the influence of housing comfort on expressivity of milking behaviours of cows in parlour, milk yield and compositions. Forty Jersey crossbred cows of similar production levels were selected and divided into 2 groups based on age, production and parity. Subsequently, cows were kept in two different types of loose house; each containing 20 animals. Two types of housing patterns were compared - (i) Traditional shed (T0) and (ii) Thermo-comfortable shed (T1). Impact of housing comfort significantly transformed the expressions of dairy cows behaviour even in milking parlour. Milking temperament scores and stepping during milking were significantly lower in cows kept in T1 compared to that of T0. Cows of thermo-comfortable shed showed more docile, calm and less nervous behaviour than those kept in traditional shed. Housing patterns significantly influenced daily milk yield (kg) being 2.86% more in T1 as compared to T0. Similarly milk compositions were better and significantly higher in T1 group of cows than that of T0. It was concluded that staying comfort of living by resignificantly modulated the expression of dairy cows behaviours even in milking parlour, demonstrated favourable milking temperament, reduced nervousness, enhanced milk yield and showed better milk compositions in Jersey crossbred cows

Bioleaching of nickel from spent petroleum catalyst using Acidithiobacillus thiooxidans DSM-11478.

The present work deals with optimization of culture conditions and process parameters for bioleaching of spent petroleum catalyst collected from a petroleum refinery. The efficacy of Ni bioleaching from spent petroleum catalyst was determined using pure culture of Acidithiobacillus thiooxidans DSM-11478. The culture conditions of pH, temperature and headspace volume to media volume ratio were optimized. EDX analysis was done to confirm the presence of Ni in the spent catalyst after roasting it to decoke its surface. The optimum temperature for A. thiooxidans DSM-11478 growth was found to be 32 °C. The enhanced recovery of nickel at very low pH was attributed to the higher acidic strength of sulfuric acid produced in the culture medium by the bacterium. During the bioleaching process, 89% of the Ni present in the catalyst waste could be successfully recovered in optimized conditions. This environment friendly bioleaching process proved efficient than the chemical method. Taking leads from the lab scale results, bioleaching in larger volumes (1, 5 and 10 L) was also performed to provide guidelines for taking up this technology for in situ industrial waste management.