P. J. Murray

The influence of goat genotype on the production of Capretto and Chevon carcasses. 2. Meat quality.

The effect of five goat genotypes, Boer×Angora (BA), Boer×Saanen (BS), Feral×Feral (FF), Saanen x Angora (SA) and Saanen x Feral (SF) on the meat quality of Capretto and Chevon carcasses obtained from 50 buck kids, was assessed. Genotype had an influence on cooking loss and longissimus thoracis muscle colour coordinates (CIE L(*), a(*), b(*) values). BS kids from the Capretto group had paler muscle colour compared to other genotypes; pale muscle colour being required for Capretto carcasses. Total pigment concentration, fat colour, shear force values and sensory scores for flavour, tenderness, juiciness and overall acceptability did not differ significantly between genotypes. Muscle colour became darker and fat colour became more yellow with increasing animal age. Tenderness decreased with animal age as indicated by higher shear force values. Age had no significant influence on cooking loss and sensory scores.

The influence of goat genotype on the production of Capretto and Chevon carcasses. 1. Growth and carcass characteristics

Fifty buck kids from five goat genotypes, Boer × Angora (BA), Boer × Saanen (BS), Feral × Feral (FF), Saanen × Angora (SA) and Saanen × Feral (SF) were compared for production of Capretto and Chevon carcasses. BS and SF kids had significantly better average daily gain compared to other genotypes and took less time to reach the required liveweight for Capretto and Chevon production. The development of visceral organs was not influenced by genotype. Kids from dairy breeds (SA in case of Capretto and SF in case of the Chevon group) deposited more internal fat in comparison to other genotypes. Dressing percentage (based on empty body weight) of kids ranged from 50-55%. At the same liveweight, dressing percentage and eye muscle dimensions did not vary between genotypes. However, BS and SF kids produced longer carcasses. Subcutaneous fat thickness was significantly greater in Chevon carcasses from BA compared to other genotypes. A high correlation was found between fat thickness measured by ultrasound on the live animal and ruler measurement on the carcass at the 12/13th rib position. Based on growth and carcass characteristics BS and SF kids performed better than kids from other genotypes used in the present study.

Thirty years later: enrichment practices for captive mammals.

Environmental enrichment of captive mammals has been steadily evolving over the past thirty years. For this process to continue, it is first necessary to define current enrichment practices and then identify the factors that limit enhancing the quality and quantity of enrichment, as well as the evaluation of its effectiveness. With the objective of obtaining this information, an international multi-institutional questionnaire survey was conducted with individuals working with zoo-housed mammals. Results of the survey showed that regardless of how important different types of enrichment were perceived to be, if providing them was particularly time-consuming, they were not made available to captive mammals as frequently as those requiring less staff time and effort. The groups of mammals provided with enrichment most frequently received it on average fewer than four times per day, resulting in less than two hours per day spent by each animal care staff member on tasks related to enrichment. The time required for staff to complete other husbandry tasks was the factor most limiting the implementation and evaluation of enrichment. The majority of survey respondents agreed that they would provide more enrichment and carry out more evaluation of enrichment if it was manageable to do so. The results of this study support the need for greater quantity, variety, frequency, and evaluation of enrichment provided to captive mammals housed in zoos without impinging on available staff time.

Feral goats in Australia: A study on the quality and nutritive value of their meat

The purpose of this study was to determine the quality of fresh and cooked meat, and the nutritive value of this meat from 62 male Australian feral goats. The goats were slaughtered at 5, 10, 20, 30, 40, 50, 60 and 70kg liveweights. Half of the goats were castrated and half were left as intact animals. The quality profiles of meat (e.g. pH, colour, pigment concentrations, cooking loss, shear force value and eating quality of cooked meat) from both castrated and intact feral goats started to decrease when animals were slaughtered at heavier liveweights (e.g. above 40kg). The nutritive value of the meat (chemical compositions, fatty acids and total cholesterol concentrations) changed when animals were castrated and had heavier slaughter weights. Overall, we recommend that 40kg liveweight is the heaviest slaughter weight, since the quality characteristics of meat will be lower when feral goats were slaughtered above 40kg liveweight.

Part 2. Carcass composition and fatty acid profiles of adipose tissue of male goats: effects of genotype and liveweight at slaughter

The dissected carcass composition and fatty acid profiles of intermuscular fat from 110 male goat kids from six genotypes i.e. Boer x Angora (BA), Boer x Feral (BF), Boer x Saanen (BS), Feral x Feral (1717), Saanen x Angora (SA) and Saanen x Feral (SF) and two slaughter weight groups i.e. Capretto and Chevon (liveweight at slaughter 14-22 and 30-35 kg, respectively) were compared. Carcass tissue distribution for various genotypes was: muscle (63-66%), fat (10-13%) and bone (21-24%). Genotype significantly (P l 0.05) influenced the carcass composition; BA and FF carcasses had significantly higher muscle to bone ratio, while carcasses from BS kids were leaner compared to other genotypes. However, the two slaughter weight groups did not differ significantly (P g 0.05) in terms of carcass composition, when compared at the same carcass weight. In the present study, significant (P l 0.01) correlations were observed between percentage of muscle, fat and bone in most of the primal cuts and that in the carcass side. The main saturated fatty acids (SFAs) identified were palmitic (16:0) and stearic acid (18:0), while oleic acid (18: 1, omega9) was the main unsaturated fatty acid (UFA) in the intermuscular fat from goat kids. There were significant (P l 0.05) differences between genotypes in the proportions of individual fatty acids. Adipose tissue from BS kids had significantly higher UFAs (mainly oleic acid) and thus had a significantly lower melting point compared to other genotypes. There were significantly higher proportions of palmitic acid (35%) in the adipose tissue from Capretto kids compared to that from Chevon kids (22%). The concentration of UFAs increased in the adipose tissue from Capretto to Chevon carcasses

The influence of goat genotype on the production of Capretto and Chevon carcasses 3. Dissected carcass composition.

The dissected composition from left sides of the carcasses obtained from 50 buck kids from five goat genotypes (10 kids/genotype), Boer x Angora (BA), Boer x Saanen (BS), Feral x Feral (FF), Saanen x Angora (SA) and Saanen x Feral (SF), was compared at two age groups. The muscle content of various primal cuts varied between 53 and 73% for Capretto and Chevon groups, with minor differences between genotypes. SA kids had significantly higher separable carcass fat compared to BS and SF for the Capretto group, while Chevon carcasses from BA and SF deposited more carcass fat than FF. The bone content (19-21%) of the carcass side did not differ significantly between genotypes for the Chevon group. The dissected carcass components (muscle, fat and bone) were significantly correlated with those components of most of the individual cuts. The percentage carcass muscle and fat increased and bone content decreased significantly with age.

The influence of goat genotype on the production of Capretto and Chevon carcasses. 4. Chemical composition of muscle and fatty acid profiles of adipose tissue

The chemical composition of muscle and the fatty acid composition of adipose tissue from the carcasses obtained from 50 buck kids from five genotypes (10 kids/genotype), Boer x Angora (BA), Boer x Saanen (BS), Feral x Feral (FF), Saanen x Angora (SA) and Saanen x Feral (SF) reared for Capretto and Chevon production, were compared. Genotype did not influence the chemical composition of muscle except for muscle from BA carcasses, which had significantly higher extractable fat content. The proportions of individual fatty acids differed significantly between genotypes for the Capretto kids. Adipose tissue from the Capretto group had a higher concentration of palmitic acid (31-34%), while the proportion of oleic acid (37-40%) was greater in the Chevon group. With an increase in age and resultant change in diet, the saturated fatty acid concentration decreased and the unsaturated fatty acid concentration increased.

Increasing the efficacy of Judas goats by sterilisation and pregnancy termination

The use of Judas goats to locate remnant animals is a potentially powerful tool for enhancing goat-eradication efforts, which are especially important to island conservation. However, current Judas goat methodology falls short of its potential efficacy. Female Judas goats are often pregnant at the time of deployment or become impregnated in the field; pregnant females leave associated goats to give birth, causing downtime of Judas goat operations. Further, male Judas goats may inseminate remnant females. Sterilising Judas goats prior to deployment removes these inefficiencies. Here, we describe two methods (epididymectomy for males and tubal occlusion for females) that sterilise Judas goats while still maintaining sexual motivation and other behaviours associated with intact animals. These surgeries are straightforward, time efficient, and may be conducted in the field by staff with minimal training. Given the widespread and deleterious impacts of non-native herbivores to ecosystems and the importance of Judas operations in detecting animals at low densities, sterilisation and termination of pregnancy should be applied routinely in Judas goat (and possibly other species) programs to increase the efficacy of low-density control operations and eradication campaigns.

Corneal Fibropapillomatosis in Green Sea Turtles (Chelonia mydas) in Australia.

Chelonid corneal fibropapillomatosis has not previously been recorded in Australian waters. During 2008, 724 green sea turtles (Chelonia mydas) were examined in Queensland, Australia at two sites, Moreton Bay (n=155) and Shoalwater Bay (n=569), during annual monitoring. In the same calendar year, 63 turtles were submitted from various sites in southern Queensland for post-mortem examination at the University of Queensland. Four of the 787 animals (0.5%) were found to have corneal fibropapillomas of varying size, with similar gross and microscopical features to those reported in other parts of the world. Two animals with corneal fibropapillomas also had cutaneous fibropapillomas. Clinical assessment indicated that these lesions had detrimental effects on the vision of the turtles and therefore their potential ability to source food, avoid predators and interact with conspecifics. Importantly, these findings represent an emergence of this manifestation of fibropapillomatosis in green sea turtle populations in the southern Pacific Ocean.

Pest Responses to Odors From Predators Fed a Diet of Target Species Conspecifics and Heterospecifics

Abstract Research into the use of predator-odor–based repellents as a management tool has gained momentum during the past 30 years. Some studies have suggested that odors from a predator whose diet includes the target species are more effective than odors from a predator that does not consume the species. To evaluate this management tool in the Australian context and to determine the effect, if any, of predator diet on odor repellence, we tested eutherian and metatherian, predator fecal odors on phylogenetically separated pest species that currently occur in Australia. We evaluated fecal odors from tigers (Panthera tigris) and Tasmanian devils (Sarcophilus harrisii) as repellents for goats (Capra hircus) and eastern grey kangaroos (Macropus giganteus). We fed tigers and Tasmanian devils 2 diets: one of goat and one of eastern grey kangaroo. The test fecal odors were more effective than a control odor of carrier material and solvent at deterring goats (P < 0.001) and kangaroos (P  =  0.02) from food. Tiger fecal odor was more effective than Tasmanian devil odor in deterring both goats (P  =  0.001) and kangaroos (P  =  0.03). We observed a decrease in the number of feeding events for goats when they were exposed to the odor from a tiger fed goat compared with all other predator–diet combinations (P < 0.001). We also observed a decrease in feeding events for kangaroos when exposed to the odor from a tiger fed kangaroo compared with all other predator–diet combinations. We observed signs of desensitization to the test odors in goats and habituation to the test odors in kangaroos over the experimental period. A better understanding of the factors involved in desensitization and habituation may increase the effectiveness of fecal odor–based repellents as a humane and nonlethal management tool for managers.