Suppression of oestrus is of major interest in feral cat populations, but also in breeding queens temporarily not intended for breeding. Slow release gonadotropin-releasing hormone (GnRH) agonist implants are a new off-label approach for reproduction control in cats. However, initially, oestrus induction may occur and no data exist regarding what happens if previously mated queens are treated. This case report presents a queen mismated 9 and 8 days before treatment with a 4.7 mg deslorelin implant. The queen delivered four healthy kittens 66 days after mismating, but showed no interest in the kittens and lactation was not adequate. Progesterone and oestradiol concentrations were monitored and the queen was followed until the return of oestrus and subsequent breeding. The next oestrus was observed 498 days after treatment and the queen was mated in the second oestrus afterwards, became pregnant and delivered two healthy kittens, both of which were raised successfully by the queen. This case report clearly shows that pregnancy following a GnRH-agonist implant may go to term, but maternal care might be influenced owing to hormonal changes induced by treatment. In addition, this is the first report demonstrating reversibility of effects induced by long-term treatment with a deslorelin implant (return to oestrus, fertility and normal maternal care).
The conversion of bacterial CRISPR/Cas defense system into a simple and efficient tool for genome manipulations brought experimental biology into new dimensions. Suddenly, genome editing reached many groups most of which were interested in it but not able to employ the available time-and labor-consuming approaches of the pre-CRISPR era. In plant biology and biotechnology, CRISPR/Cas gene editing became the second most important technology after plant transformation. Actually, it relies on the available array of methods of gene delivery. While sufficient for most purposes, the classic gene transfer methods might become a problem for some experimental settings. The main obstacle is that they include DNA delivery and, frequently, its subsequent integration into cellular genome. For this reason novel methods to achieve gene editing without the need of stable transformation and even without DNA delivery were developed. These new approaches include in vitro ribonucleoprotein complexes formulations (delivered by microinjection, particle bombardment, electroporation, liposomes etc.), use of virus-like particles and employment of bacterial secretory systems for Cas/gRNA delivery. The first attempts to achieve DNA-free editing were made less than ten years ago. Later, different types of animal and plant cells were addressed. In this mini review we try to summarize the current developments and emerging trends in the field of DNA-free editing in plants.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.