The effect of cereal processing on the lactation performance of Chios sheep and Damascus goats and the pre-weaning growth of their offspring

Cereals level and source effects on rumen fermentation, colostrum and milk properties, and blood metabolites in periparturient ewes

Optimal type and dietary inclusion rates of cereal grains for periparturient sheep are unknown. The objective was to determine effects of feeding diets with high (H) v. low (L) levels of ground corn grain (CN) v. combined ground wheat and barley grains (WB) on intake, rumen fermentation, colostrum and milk properties, and blood metabolites of periparturient sheep. Twenty Afshari×Merino ewes were used in a completely randomized design study from 24 days prepartum through 21 days postpartum. Ewes were kept indoors in individual boxes and received once daily at 0900 h total mixed rations. Treatments were mixed rations containing either (1) H or (2) L concentrate based on either (1) 100% CN or (2) 50 : 50 ratio of ground wheat : ground barley grains in a 2×2 factorial arrangement. Each treatment group had five ewes including two twin-lamb ewes and three single-lamb ewes. Postpartal dry matter intake (DMI) increased by feeding high CN v. high and low WB, while high v. low CN improved postpartum DMI. The DMI during lambing tended to increase with the high v. low WB. Feeding CN v. WB, and feeding both CN and WB at L v. H level increased fecal pH. Postpartal rumen pH was lower with the high v. low WB (5.7 v. 6.2). Rumen concentrations of propionate were lower and of acetate were higher with L v. H grain levels. Increased dietary grain reduced urine pH for WB (7.24 v. 7.83) but not for CN (7.63 v. 7.52) prepartum. Colostrum properties, postpartal urine pH, lamb weight at birth and 21 days of age, and placental weight and expulsion time were unaffected. Milk yield increased and milk fat yield tended to increase by H v. L grain diets. Plasma glucose was increased by feeding high v. low WB, whereas CN v. WB tended to reduce peripartal plasma non-esterified fatty acids (NEFA) and increased insulin to NEFA ratio. In conclusion, more cereal grains can be included in periparturient sheep diets and CN instead of WB may be fed to periparturient sheep to improve energy status. Findings suggest opportunities to optimize periparturient ewe physiology and performance through feeding certain cereals and avoiding high levels of WB.

Effect of grain processing on the performance of early-weaned lambs and kids

The effect of grain processing and form of the concentrate mixture were studied on early-weaned Chios lambs (42 days of age) and Damascus kids (56 days of age). Forty-five, 36, 33 and 33 animals were used in trials 1 (lambs), 2 (lambs), 3 (kids) and 4 (kids), respectively. Within trials animals were divided on the basis of live weight and age into three groups. Treatments (three forms of concentrate mixture) were randomly allocated to one of the three groups. The treatments were: whole cereal (WGP) grains mixed with pellets made from the other ingredients of the concentrate mixture; pelleted (P), where all ingredients were ground and pelleted in 5-mm cubes; rolled cereal grains (RGP), where cereal grains were rolled and then mixed with pellets (5-mm cubes) made from the other ingredients of the concentrate mixture. Cereal grains comprised 774 g/kg concentrate mixture. Fattening diets were based on ad libitum feeding of concentrates and a daily allowance of 01 kg per animal of long lucerne hay. Digestion coefficients, outflow rate of small particles from the rumen and rumen metabolites were measured using five animals per species per treatment.

There were no significant differences between diets for live-weight gain in lambs. On the other hand, kids on the P diet gained more weight and had better food to gain ratio than the other two diets. Feeding the P diet resulted in a significant decrease of acetate and butyrate molar proportion ( P < 0·001) and an increase (P < 0·001) of propionate molar proportion. Similarly, feeding the P diet resulted in a significant reduction in ruminal pH (P < 0·01) and NH,-N (P < 0·05) concentration. Outflow rate (% per h) of small particles from the rumen was lower from lambs and kids on the P diet (P < 0·001). There were no significant differences between species and/or among diets for apparent digestion coefficients and nitrogen balance.

Alternatives for Improving Physical, Chemical, and Sensory Characteristics of Goat Cheeses: The Use of Arid-Land Forages in the Diet

To establish the effect of an alternative diet on the quality of Majorero cheese, the basic physicochemical parameters, fatty acid profile, and sensory characteristics were studied. Two groups of 20 Majorero goats were fed 2 different diets: a forage diet (DF), which had a high ratio of long fiber to concentrates (65:35), and a concentrate diet (DC), with a low ratio of long fiber to concentrates (35:65). The DF dietary fiber was supplied by native forages adapted to arid land. A total of 42 Majorero goat cheeses were used for this study: 21 in the DF group and 21 in the DC group. Seven cheeses from each group were tested after 2, 15, and 60 d of ripening. The milk produced by goats fed the DF diet had a higher fat concentration. No significant differences were observed in the milk fatty acid profile. The diet affected the chemical composition of the cheese in pH and fat content, and fat was significantly higher in cheeses made from DF milk than those from DC milk. Dietary characteristics had important effects on the medium-chain fatty acid composition (C6 to C14) of the cheese fat, giving DF cheeses the specific goat's milk flavor that is sought after for this type of cheese. The fatty acid composition (%) differed substantially among different ripening times. The DF cheeses were more appreciated by the panelists, as they had a greater variety of odors and flavors than the DC cheeses. The DF hard cheeses were described as having vegetable and fruity tones as well as tones of hay and dried fruit.

Forage of different physical forms in the diets of lactating Granadina goats: nutrient digestibility and milk production and composition

To determine whether the energy balance of goats or characteristics of the diet consumed were the principal factors that determined milk production, feeding and digestion trials were carried out using two groups of 5 Granadina goats. The concentrate fraction of both diets was the same, but the forage fraction of the diets differed. In diet 1, the forage was in the form of long alfalfa hay, and, in diet 2, forage was in the form of pelleted alfalfa. Intake and the forage to concentrate ratio of the two diets were not significantly different, although diet 2 was more digestible. The amount of fat and protein in the milk depended on energy intake and not on dietary treatment. The milk protein of goats fed diet 2 was higher in casein. No sensible differences were noted in the fatty acid composition of the milk. Nitrogen and metabolizable energy utilization for milk production was greater for goats fed diet 2. According to the results obtained, it would seem advantageous to use pelleted alfalfa rather than alfalfa hay in the diets of goats.