Minors in graphs of large $θ_r$-girth

For every $r \in \mathbb{N}$, let $θ_r$ denote the graph with two vertices and $r$ parallel edges. The $θ_r$-girth of a graph $G$ is the minimum number of edges of a subgraph of $G$ that can be contracted to $θ_r$. This notion generalizes the usual concept of girth which corresponds to the case $r=2$. In [Minors in graphs of large girth, Random Structures & Algorithms, 22(2):213--225, 2003], Kühn and Osthus showed that graphs of sufficiently large minimum degree contain clique-minors whose order is an exponential function of their girth. We extend this result for the case of $θ_{r}$-girth and we show that the minimum degree can be replaced by some connectivity measurement. As an application of our results, we prove that, for every fixed $r$, graphs excluding as a minor the disjoint union of $k$ $θ_{r}$'s have treewidth $O(k\cdot \log k)$.