Let F be a flock of the quadratic cone Q: X 2=X1X3 , in PG(3, q), q even, and let 6t : X0 =xt X1 + t X2 +zt X3 , t # Fq , be the q planes defining the flock F. A flock is equivalent to a herd of ovals in PG(2, q), q even, and to a flock generalized quadrangle of order (q, q). We show that if the herd contains a monomial oval, this oval is the Segre oval. This implies a result on the existence o...

The impact of maternal flock age and incubation on embryo metabolism was studied to understand late incubation overheating and mortality in Ross 308 embryos. Fresh broiler hatching eggs (n = 45) were obtained from commercial breeder flocks at 3 ages: Young (Y): 25 to 34 wk, Peak (P): 35 to 45 wk, Old (O): 46 to 54 wk of age), stored for 2 to 4 d at 18°C and 73% RH, then incubated for 14 d at 37...

Flocks of birds are highly variable in shape in all contexts (while travelling, avoiding predation, wheeling above the roost). Particularly amazing in this respect are the aerial displays of huge flocks of starlings (Sturnus vulgaris) above the sleeping site at dawn. The causes of this variability are hardly known, however. Here we hypothesise that variability of shape increases when there are ...

The objectives of the two studies presented were to estimate the prevalence of Campylobacter-positive farms and flocks and to acquire updated knowledge about risk factors for the introduction of Campylobacter in Danish broiler flocks. In the first study, from September 2010 to September 2011, there were 25 Danish broiler farms visited, and a questionnaire was filled in by a veterinarian/consult...

Flock health is one of the most critical areas of management that can affect the overall productivity and ultimately the profitability of a flock of sheep. Failure to provide adequate attention to flock health can have disastrous effects on both the welfare of your sheep and your bank account. However, by implementing proper flock health management practices, you can minimize your exposure to p...

Trials were conducted to determine general semen characteristics of the male native chicken and effects of mating ratio, cock number in the flock, and breeder age on fertility in the native chicken flock. The results revealed that the mature native male had the semen volume of about 0.4 ml/bird/ejaculation, spermatocrit value of about 13.86-15.60%, semen concentration of about 7031-8001 million...

Over the past several years increasing of cellulites in some regions of the country has been reported. During August and September of 2005, 4.48% of total slaughtered broilers were condemned due to cellulitis in Masjid Soleiman slaughterhouse. Four out of 98 slaughtered flocks were infected to cellulitis. The condemnation rates in infected flocks were: flock 1: 1.55%, flock 2: 0.993%, flock 3: ...

This study aimed to discern the contribution of poultry farms to the contamination of the environment with ESBL-producing Escherichia coli and therewith, potentially to the spread of these bacteria to humans and other animals. ESBL-producing E. coli were detected at all investigated laying hen farms (n = 5) and broiler farms (n = 3) in 65% (46/71) and 81% (57/70) of poultry faeces samples, resp...

The problem of reaching a consensus in a group of autonomous agents has been the object of study in a number of situations ranging from linguistics [11, 18, 20] to distributed computing [25, 26] and from physics [27] to animal behavior [6, 13, 23, 24]. Research on the latter attempts to explain, by appropriately modeling it, the observed behavior of a group of animals, say a flock of birds, who...

*Correspondence: S. S. Manna, Department of Theoretical Sciences, Satyendra Nath Bose National Centre for Basic Sciences, Block-JD, Sector-III, Salt Lake, Kolkata-700098, West Bengal, India e-mail: [email protected] A simple model of the two dimensional collective motion of a group of mobile agents has been studied. Like birds, these agents travel in open free space where each of them interacts...