J. L. López

Effects of refrigeration, freezing-thawing and pasteurization on IgG goat colostrum preservation

The aim of this paper was to evaluate the effects of refrigeration, several different methods of thawing, and pasteurization on the concentration of IgG in goat colostrum. Three different experiments were designed to analyse these effects. In the first of these, 50 samples of goat colostrum were stored in a cold-storage room at a temperature of 4 ◦ C for a 3-month period. No statistically significant effects were observed within this time, although there was a reduction in IgG concentrations (32.98 and 25.11 mg/ml IgG at day 0 and 91, respectively). In the second experiment, 20 samples of goat colostrum were frozen and subsequently thawed using four different methods: hot water (60 ◦ C), refrigeration (4 ◦ C), room temperature (27 ◦ C) and microwave (55 ◦ C). The process was carried out seven times for each of the four methods. The method of thawing did not affect the colostrum IgG concentration. However, the repetition of freezing and thawing tended to reduce IgG concentrations, albeit to no significant degree (15.50 and 10.73 mg/ml IgG at cycle 0 and 7, respectively). In the third experiment, 30 goat colostrum samples were used and a reduction of approximately 35% of IgG concentration after pasteurization was observed. Refrigeration, freezing and pasteurization are suitable methods for conserving goat colostrum.

Starvation before slaughtering as a tool to keep freshness attributes in gilthead sea bream (Sparus aurata)

Instrumental quality parameters related to freshness were evaluated for gilthead sea bream (Sparus aurata) after different storage periods on ice (2, 4, 7 and 11 days of storage) for one, four and eight days of pre-slaughter starvation. The study was carried out on 360 gilthead sea bream from five different groups reared on a commercial fish farm. Starvation period had a significant effect on fish texture: the force necessary to compress 4 mm of flesh after two days ice storage in 1 day starved fish (16.50 ± 0.59 Newtons) was less than that for four day (18.98 ± 0.63 Newtons) and eight day starved fish (20.43 ± 1.12 Newtons). Significant differences in flesh puncture and flesh compression were not detected, although these values did increase with increasing starvation period. A significant increase in pH and myofibrilar protein solubility was also detected for fish starved for one day.

Prediction of kid carcass composition by use of joint dissection

Abstract Forty-seven Canary Caprine Group kids (6–15 kg body weight) were taken from the experimental flocks of Las Palmas de Gran Canarias University and the Canary Agronomic Science Institute and slaughtered. Their carcasses were halved and the left side was dissected into the major tissues. Linear regression analyses were used for predicting carcass tissue composition, using half carcass weight and joints tissue weights as independent variables. Taking account of the relative economic values of the joints, the most cost-effective predictor of carcass tissue composition was a combination of half carcass weight and shoulder dissection with an r 2 of 0.79, 0.81, 0.72 and 0.70 for muscle, bone, and subcutaneous and intermuscular carcass fat, respectively.

Influencia histórica y actual de los genotipos canarios en la población caprina americana

Resumen En la ultima decada del siglo XV comenzo lacolonizacion americana y termino laconquista de las Islas Canarias. El caracterinsular de paso obligatorio en las rutascolombinas hizo que ambos territorios sevincularan estrechamente y compartieranuno de los pilares basicos de la economia deaquella epoca: la ganaderia. En este trabajose presenta una revision bibliografica decaracter historico y zootecnico de la cual sedesprende que las razas caprinas de origenafricano en Canarias no solo tuvieron unaimportante influencia en la constitucion delmosaico racial americano sino que, ademas,comienzan a ser demandadas en esas areasdebido a sus caracteristicas rusticas yproductivas. Summary The last decade of the 15 th century saw thebeginning of the American colonisation andthe end of the conquest of the CanaryIslands. The fact that the islands were on theroutes which Columbus used, meant thatboth territories became closely connected andshared one of the basic pillars of economy atthat time: livestock. In this work abibliographical review of the historical andbiological characteristics is presented,inferring that the caprine breeds of Africanorigin in the Canary Isles had an importantinfluence in the constitution of the Americanmosaic of breeds and breed types.

Carcass Composition of Canary Caprine Group at Adult Age

Abstract Arguello, A., Fabelo, F., Capote, J., Gines, R., Afonso, J.M. and Lopez, J.L. 1999. Carcass composition of canary caprine group at adult age. J. Appl. Anim. Res., 15: 75–79. To study the carcass characteristics of mature goats from the Canary Caprine Group (CCG) 14 goats were slaughtered at adult age. The average live weight at slaughter was 57.88±2.44 kg, the hot carcass weight 25.33±1.52 kg and 2.17±0.33% chilling loss. The carcass yield amounted to 48.71±0.78%. The empty digestive tract, skin, udder and head contributed to over 75% of the total offals. In the left half of the carcass long leg accounted for 32%, shoulder 19%, ribs 23%, neck 9% and flank 17%. The carcass contained 61.79% muscle, 16.87% fat and 21.34% bone. Efforts have been made to predict certain parameters based on net live weight (live weight-digestive tract contents).

Effect of electronic identification with ruminal bolus on growth parameters and stomach development in young goat kids

Although most of the European goat farms are dairies, there are a significant number of herds dedicated to meat production as the main product. Due to the current policy of food safety in European Union, the traceability, particularly the electronic identification, is taken into consideration; however, the effect of this electronic identification has not been studied on goat kids for fattening. For this reason, the effect of the ruminal bolus on the growth of goat kids and the development of their stomachs were studied. At 16 kg, animals were randomly assigned in two groups: control (n=23) and bolus (n=27), the latter identified with Inoxeramic Bolus. Both of them were slaughtered at 24 kg. Statistical differences in growth parameters and stomach development were not observed, except in the reticulum-omasal orifice diameter, which was bigger in the bolus group. Moreover, when the breed was taken into account (Majorera, Palmera and Tinerfeña), interbreed differences were found in orifice diameter and empty rumen–reticulum weight, due to treatment (P<0.05).

Effects of Live Weight at Slaughter on Tissue Distribution in Kids

Abstract Argüello, A., Capote, J., Marichal, A. and López, J.L. 2002. Effects of live weight at slaughter on tissue distribution in kids. J. Appl. Anim. Res., 23: 43–48. To study the effects of live weight at slaughter (LWS; 6, 10, 25 kg), forty-five twin male kids from Canary Caprine Group breed were compared. No significant differences were found in any extra category cuts. In first category cuts kids slaughtered at 25 kg LWS had significantly more subcutaneous as well as total fat and less total bone, whereas in second category cuts, this group had more muscles. In conclusion, increased LWS from 6 to 10 or 25 kg have no effect in tissue distribution in extra category cuts and some effect in first and second category cuts.

A Note on Yoghurt Utilisation in Artificial Rearing of Kids

Abstract Arguello, A., Gines, R. and Lopez, J.L. 1999. A note on yoghurt utilisation in artificial rearing of kids. J. Appl. Anim. Res., 15: 165–168. Eleven kids from the Canary Caprine Group were fed on a mixture of 50% commercial milk replacer and yoghurt. The growth rate was 91.3 g/d and the net carcass yield 48.70% with 6.22%, 26.97% and 60.12% fat, bone and muscles, respectively. The pH of muscles fell significantly in 24 h post-slaughter. Use of yoghurt in scarcity can be tried.