We show that for every finite set $R$ of positive integers, there is an
integer $n_0=n_0(R)$ such that every $R$-uniform hypergraph $\mathcal{H}$ on
$n$ ($n\geq n_0$) vertices with minimum co-degree $\delta_2(\mathcal{H})\geq 1$
contains a Berge cycle $C_s$ for any $3\leq s\leq n$. For $R= \{3\}$, we show
that every $3$-graph on $n\geq 7$ vertices with co-degree at least one contains
a Hamiltonian Berge cycle. As an application, we determine the maximum
Lagrangian of $k$-uniform Berge-$C_{t}$-free hypergraphs and Berge-$P_{t}$-free
hypergraphs.