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We studied the effects of goat and cow milk fat on the digestive utilization of this nutrient and on some of the biochemical parameters that are related to the metabolism of lipids, using rats with a resection of 50% of the distal small intestine and control animals (transected). The fat content in all the diets was 10% but the lipid quality was varied: the standard diet was based on olive oil, while the other two diets included fat obtained from lyophilized goat milk and cow milk, respectively. The digestive utilization of the fat was lower in the resected animals than in the transected ones for all three diets studied. In both resected and transected animals, the apparent digestibility coefficient (ADC) of the fat was greater with the standard diet (olive oil) than with diets whose fat content was provided by goat or cow milk. The digestive utilization of the fat was greater in the transected and resected rats receiving a diet of goat's milk (rich in medium-chain triglycerides) than those given a cow-milk-based diet, and more closely approached the values obtained for olive oil. The consumption of goat milk reduced levels of cholesterol while levels of triglycerides, HDL, GOT and GPT remained within the normal ranges, for both transected and resected animals. The advantageous effect of goat milk on the metabolism of lipids with respect to cow milk suggests that the former should be included in the diet in cases of malabsorption syndrome.

A 3-year experiment compared in an olive orchard the effect of different cover crops' composition on runoff, water erosion, diversity of annual plants, and arthropod communities which could provide an alternative to conventional management based on tillage (CT). The cover crops evaluated were a seeded homogeneous grass (GC), a seeded mix of ten different species (MC), and a non-seeded cover by vegetation naturally present at the farm after 20 years of mowing (MC). The results suggest that heterogeneous cover crops can provide a viable alternative to homogeneous ones in olives, providing similar benefits in reducing runoff and soil losses compared to management based on bare soil. The reduction in soil loss was particularly large: 46.7 in CT to 6.5 and 7.9 t ha year in GC and MC, respectively. The heterogeneous cover crops resulted in greater diversity of plant species and a modification of the arthropod communities with an increased number of predators for pests. The reduction of the cost of implanting heterogeneous cover crops, improvement of the seeding techniques, and selection of species included in the mixes require additional research to promote the use of this practice which can deliver enhanced environmental benefits.

The influence of the source of dietary Fe (ferric citrate alone or mixed with bovine blood at a proportion of 1 : 1 (v/v)) on the digestive utilization of Fe, P, Ca and Mg, and on haemoglobin regeneration efficiency (HRE) was investigated in control and Fe-deficient rats. Diet A contained (by analysis) 43.5 mg Fe/kg diet (as ferric citrate), and diet B contained 44.3 mg Fe/kg diet (ferric citrate-bovine blood). In Fedeficient rats fed on diet A or B the apparent digestibility coefficient (ADC) of Fe increased by 42.3 and 45.7 YO respectively. The ADC of Ca and Mg decreased significantly in Fe-deficient rats regardless of the source of dietary Fe. The H R E increased by 72.9% in Fe-deficient rats fed on diet A, and by 91

1 The presence and abundance of arthropods were compared in three olive orchards under organic, integrated and conventional management regimes. In each olive orchard, trees were sampled in the canopy by beating branches and soil arthropods by placing pitfall traps. Contrary to expectations, the highest abundance of arthropods occurred in the integrated management orchard. The most abundant groups were Formicidae and the species Euphyllura olivinae (Homoptera: Psyllidae). 2 Canopies and the soil under the tree canopy (interior soil) were selected as the most informative sites for sampling. The months with the strongest differences were May, June and July, especially June. In the canopy, Araneae, Coleoptera, Diptera, Heteroptera, Hymenoptera, Homoptera, Lepidoptera, Neuroptera and Thysanoptera were the most abundant, and showed significant differences in abundance among orchards with different management regimes. Moreover, in the canopies, Coleoptera and Lepidoptera showed a seasonal pattern of abundance and consistent significant differences between the organic orchard vs. the integrated and conventional ones in both years of study. In the soil, 12 orders showed significant differences in abundance among management regimes at some point of the sampling season. 3 In a search for biological indicators that could help to distinguish between management regimes, a discriminant analysis applied to the data indicated that only the samples from the canopy were classified according to their management regime in a consistent way over time. The groups selected by the analysis to establish differences among management regimes were Coleoptera, Diptera, Heteroptera, Lepidoptera and Thysanoptera. The analysis applied to compare organic vs. non-organic olive orchards, again identified Coleoptera and Lepidoptera as suitable groups. The results suggest that these two orders are potential bioindicators to distinguish, in a simple way, organic olive orchards from non-organic ones.

Records of yield and reproduction from 4293 Holstein and 2143 Jersey first lactation cows from eight Holstein and six Jersey herds were utilized to evaluate genetic parameters for Florida, a subtropical environment. Statistical analyses were by derivative-free REML with the animal model. Genetic variances were based on variation in estimated breeding values of individual cows. Heritabilities were .27 to .43 for yields (6 estimates), .38 to .51 for constituent percentages (4 estimates), and .025 to .056 for reproduction (6 estimates), which were similar to estimates for temperature areas from similar procedures. Also, correlations of breeding values between yields were high and between yields and reproduction were low and generally antagonistic. Correlated responses in calving interval from selection for yield, with selection intensities of 1.0 to 1.5, would be expected to lead to increases of 1.0 to 5.2 d per generation (12 estimates). Thus, estimates of genetic parameters and correlated responses in this subtropical environment did not differ appreciably from those that occur in temperate dairy areas.

Despite Fe deficiency and overload having been widely studied, no studies are available about the influence of milk consumption on antioxidant defence and lipid peroxidation during the course of these highly prevalent cases. The objective of the present study was to assess the influence of cow or goat milk-based diets, either with normal or Fe-overload, on antioxidant defence and lipid peroxidation in the liver, brain and erythrocytes of control and anaemic rats after chronic Fe repletion. Weanling male rats were randomly divided into two groups: a control group receiving a normal-Fe diet (45 mg/kg) and an anaemic group receiving a low-Fe diet (5 mg/kg) for 40 d. Control and anaemic rats were fed goat or cow milk-based diets, either with normal Fe or Fe-overload (450 mg/kg), for 30 or 50 d. Fe-deficiency anaemia did not have any effect on antioxidant enzymes or lipid peroxidation in the organs studied. During chronic Fe repletion, superoxide dismutase (SOD) activity was higher in the group of animals fed the cow milk diet compared with the group consuming goat milk. The slight modification of catalase and glutathione peroxidise activities in animals fed the cow milk-based diet reveals that these enzymes are unable to neutralise and scavenge the high generation of free radicals produced. The animals fed the cow milk diet showed higher rates of lipid peroxidation compared with those receiving the goat milk diet, which directly correlated with the increase in SOD activity. It was concluded that goat milk has positive effects on antioxidant defence, even in a situation of Fe overload, limiting lipid peroxidation.