Claw trimming every four to six months has become a routine procedure for the majority of high yielding housed dairy cows. Various methods have been described, but the Dutch Five Step method (Toussaint Raven 1985) is probably the most widely used approach around the world and has been the basis for most research. Despite being the most commonly used protocol internationally, the Dutch Five Step...

Different levels of claw vacuum during machine milking may influence milking performance and teat condition. The claw vacuum acts on the teat and is responsible for removal and transport of milk but is also causing potential effects on the teat tissue. In the absence of milk flow, the claw vacuum is similar as the system vacuum. During milk flow, the claw vacuum drops to lower levels depending ...

Lameness in dairy cows is a major cause of suffering and economic loss with up to 52% (average 20-25%) of cows becoming lame each year (Clarkson et al., 1996; Green et al., 2002). The vast majority of lameness cases are caused by a variety of non-infectious and infectious claw diseases causing severe pain, decreased milk yield, reduced reproductive performance, high culling rates and increased ...

We study some properties of the closure concept in claw-free graphs that was introduced by the rst author. It is known that G is hamiltonian if and only if its closure is hamiltonian, but, on the other hand, there are innnite classes of non-pancyclic graphs with pancyclic closure. We show several structural properties of claw-free graphs with complete closure and their clique cutsets and, using...

For s ≥ 3 a graph is K1,s-free if it does not contain an induced subgraph isomorphic to K1,s. Cycles in K1,3-free graphs, called clawfree graphs, have beenwell studied. In this paper we extend results on disjoint cycles in claw-free graphs satisfying certain minimum degree conditions to K1,s-free graphs, normally called generalized claw-free graphs. In particular, we prove that if G is K1,s-fre...

Let G be any graph and let c(G) denote the circumference of G. We conjecture that for every pair c1, c2 of positive integers satisfying c1 + c2 = c(G), the vertex set of G admits a partition into two sets V1 and V2, such that Vi induces a graph of circumference at most ci , i = 1, 2. We establish various results in support of the conjecture; e.g. it is observed that planar graphs, claw-free gra...

A graph is claw-free if it does not contain K I ,3 as an induced subgraph. A graph is KI,r-free if it does not contain KI,r as an induced subgraph. In this paper, we find bounds on the minimum number of edges needed to ensure a KI,.,.-free contains k vertex disjoint cycles. The bound on claw-free graphs is sharp.

A Hamilton circle in an infinite graph is a homeomorphic copy of the unit circle S1 that contains all vertices and all ends precisely once. We prove that every connected, locally connected, locally finite, claw-free graph has such a Hamilton circle, extending a result of Oberly and Sumner to infinite graphs. Furthermore, we show that such graphs are Hamilton-connected if and only if they are 3-...

We survey results and open problems in hamiltonian graph theory centred around three themes: regular graphs, t-tough graphs, and claw-free graphs.

We study the stability of some classes of graphs deened in terms of forbidden sub-graphs under the closure operation introduced by the second author. Using these results, we prove that every 2-connected claw-free and P 7-free, or claw-free and Z 4-free, or claw-free and eiiel-free graph is either hamiltonian or belongs to a certain class of exceptions (all of them having connectivity 2).