Introduction

Historically, the breeding of giant pandas in ex situ programmes has been difficult due to behavioural incompatibility and interanimal aggression. Because some individuals fail to mate naturally, the potential loss of valuable genes is a major concern to effective genetic management (see Chapter 21). Consistently successful artificial insemination (AI) would allow incorporating genetically valuable males with behavioural or physical anomalies into the gene pool. This strategy becomes even more powerful when used in the context of a genome resource bank (GRB), an organised repository of cryopreserved biomaterials (tissue, blood, DNA and sperm) (see Chapter 7). The use of sperm cryo-preservation and AI allows the movement of genes among zoos and breeding centres without needing to transfer animals, which is both stressful and costly.

'Assisted breeding' refers to the tools and techniques associated with helping a pair of animals propagate, from AI to embryo transfer to cloning, among others (Howard, 1999; Pukazhenthi & Wildt, 2004).

Giant Pandas: Biology, Veterinary Medicine and Management, ed. David E. Wildt, Anju Zhang, Hemin Zhang, Donald L. Janssen and Susie Ellis. Published by Cambridge University Press. # Cambridge University Press 2006.

With the exception of AI, there is not much need for most other assisted-breeding techniques for the giant panda. As will be demonstrated here, AI is quite adequate for dealing with most cases of infertility or with helping to maintain adequate gene diversity in the captive population. In fact, the major breeding facilities, especially the China Conservation and Research Centre for the Giant Panda (hereafter referred to as the Wolong Breeding Centre) and the Chengdu Research Base of Giant Panda Breeding, routinely use AI to increase pregnancy success. It is common practice at these centres to combine natural mating (with breeder males) with AI (using sperm from nonbreeders). Mate incompatibility and what is perceived as 'weak' sexual behaviour are the two most common reasons for using AI. However, the growing emphasis on genetic management (see Chapter 21) also elicits interest in assisted breeding to avoid the logistical challenges of moving pandas between facilities.

This chapter addresses four issues, the first being a comparison of the efficiency of AI only in the giant panda (without natural breeding) to the usual tactic of combining natural mating with AI (see Chapter 10). Second, we assess the efficacy of AI for enhancing reproduction in nonbreeding females who demonstrate weak behavioural oestrus or in nonbreeding males with compromised health. The third purpose is to determine the reproductive competency of semen cold stored at 4°C and used for multiple inseminations over consecutive days. Lastly, we evaluate the efficiency of AI with frozen-thawed spermatozoa using recent improvements in cryopreservation techniques (described in Chapter 7).

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