Meticulous planning is required to minimize heat-stress conditions in barns. The objective of this study was to determine optimum barn characteristics for high-yielding dairy cows under Israeli (Mediterranean) summer ambient conditions, by using a new stress model that takes ambient temperature, relative humidity and wind velocity into account. During the summers of 2004 and 2005, three meteorological stations were alternately installed in 39 barns: two stations inside the barn at the prevailing downwind direction, and a third station outside the upwind end of the barn. Ambient temperature, relative humidity, wind speed and direction were measured and recorded every 10 min for 3 to 5 consecutive days at each barn in turn. The data were collected at different geographical and climatic conditions. Therefore, the data collected by an outside station were used as covariates. A heat-stress model was used to determine the threshold temperature (THRT) at which a cow begins to increase its respiratory rate; THRT was the response variable in the statistical model. The THRT model takes in account assumed values of a cow's physiological characteristics: daily milk yield of 45 kg, containing 3.5% fat, and 3 mm fur depth. The independent variables were: orientation, barn type, roof slope, roof ridge, marginal height, roof type (fixed or sliding) and barn width. Results showed that the optimal barn for high-yielding cows is the loose-housing type, oriented with its long axis perpendicular to the prevailing wind direction. Advantageous to the design would be an open ridge or pagoda with marginal height of over 4.7 m for north-south orientation and over 5 m for east-west orientation, roof slope over 11%, and barn width between 43 and 51 m for north-south orientation but lower than 42 m for east-west orientation. A sliding roof was also found to be an excellent solution when outside yards are banned by environmental regulations.

Zinc (Zn) is essential for swine and poultry and native Zn concentrations in feedstuffs are too low to meet their Zn requirement. Dietary Zn bioavailability is affected by phytate, phytase and Zn supplemented in organic form is considered as more bioavailable than inorganic sources. A meta-analysis using GLM procedures was processed using broiler and piglet databases to investigate, within the physiological response of Zn, (1) the bioavailability of inorganic and organic Zn sources (Analysis I); (2) the bioavailability of native and inorganic Zn dependent from dietary phytates, vegetal and supplemental phytase activity (Analysis II). Analysis I: the bioavailability of organic Zn relative to inorganic Zn sources ranged, depending on the variable, from 85 to 117 never different from 100 (P > 0.05). The coefficients of determination of the regressions were 0.91 in broilers and above 0.89 in piglets. Analysis II: in broilers, bone Zn was explained by supplemental Zn (linear and quadratic, P < 0.001) and by supplemental phytase (linear, P < 0.001). In piglets, the interaction between dietary Zn and phytates/phytases was investigated by means of a new variable combining dietary phytic phosphorus (PP) and phytase activity. This new variable represents the remaining dietary PP after its hydrolysis in the digestive tract, mainly due to phytase and is called non-hydrolyzed phytic phosphorus (PPNH). Bone Zn was increased with native Zn (P < 0.001), but to a lower extent in high PP or low phytase diets (ZNN × PPNH, P < 0.001). In contrast, the increase in bone zinc in response to supplemental Zn (P < 0.001) was not modulated by PPNH (P > 0.05). The coefficients of determination of the regressions were 0.92 in broilers and above 0.92 in piglets. The results from the two meta-analyses suggest that (1) broilers and piglets use supplemented Zn, independent from Zn source; (2) broiler use native Zn and the use is slightly enhanced with supplemental phytase; (3) however, piglets are limited in the use of native Zn because of the antagonism of non-hydrolyzed dietary phytate. This explains the higher efficacy of phytase in improving Zn availability in this specie.

The effect of including thyme by-products from the distillation industry into the diet of pregnant ewes on the final quality of lamb meat was evaluated during meat storage in modified atmosphere. A total of 36 Segureña ewes were randomly assigned to three homogeneous groups. One group was fed a basal diet (BD) as control (C), whereas the diet of the other two groups was modified by substituting 10% (T1) and 20% (T2) of the BD with pellets made from 50% barley and 50% distilled thyme leaves (DTL). Meat spoilage (total viable, psychrotroph (PSY), moulds and yeasts, Enterobacteriaceae and lactic acid bacteria), thiobarbituric acid reactive substances (TBARS), colour (CIELab coordinates, metmyoglobin) and sensory characteristics of fresh lamb meat packed in modified atmosphere packaging (70% O2 : 30% CO2) were analysed after storage at 0, 7, 14 and 21 days. In general, the DTL-containing diet inhibited lipid and pigment oxidation in fresh lamb meat. Lower PSY counts and content of secondary oxidation product (TBARS) as a result of adding DTL to the ewe diet, whereas surface redness (a* values) was significantly higher on days 7 and 14. It can be concluded that thyme by-products from the distillation industry could be used as a source of natural antioxidant and antimicrobial in the feed for ewes.

The present experiment was conducted in order to evaluate the effects of caponization on growth, carcass composition and meat quality of males of a layer line reared until the 34th week of age. Two hundred and fifty males of a layer line were purchased and randomly divided in two equal groups: intact males and capons. Caponization was conducted at 45 days of age. Three slaughters were performed at the ages of 26, 30 and 34 weeks of age. Caponization did not affect feed intake and final live weight. Capons had a heavier breast and lighter leg than intact males. Lipid accumulation was enhanced by the caponization and fat was stored mainly at the fat pad and the skin of the commercial parts excluding the drumstick. The Pectoralis major muscle of capons had higher intramuscular fat content, lightness (L) and yellowness (b*) values and lower redness values (a*). In conclusion, caponization could be applied to a layer genotype in order to produce commercial chicken meat.

The use of culled potatoes was investigated in Belgian Blue double-muscled finishing cows, confined in tie stalls. The control diet (Treatment 1) consisted of concentrate and maize silage (50/50 on a dry matter (DM) basis). Potatoes either replaced 60% maize silage (Treatment 2) or 60% concentrate (Treatment 3). Diets were formulated to be isocaloric and isonitrogenous. They were fed ad libitum. Approximately 18 kg potatoes were fed daily in Treatments 2 and 3. Daily gain was not significantly altered; it decreased from 1.09 kg (Treatment 1) to 1.04 kg (Treatment 2) or increased to 1.20 kg (Treatment 3), although potatoes stimulated DM intake by 5% to 8% (P < 0.05). Feed conversion was unaffected in comparison with the control diet, when expressed in terms of DM, but energy efficiency (MJ/kg live weight gain) was substantially lower for Treatment 2 compared with Treatment 1 (89.9 v. 79.0; P = 0.046). Carcass weight, grading and composition were not affected by treatments, but potatoes increased dressing percentage (P = 0.009). Treatment had no significant effect on meat quality parameters. However, potatoes (Treatments 2 and 3) tended to decrease moisture content (P = 0.090) and tended to increase drip loss (P = 0.059) compared with Treatment 1. Because of a better animal performance and a lower feed cost, it is most appropriate to use potatoes as a replacement for concentrate. Feeding large amounts of potatoes besides concentrate may have an adverse effect on the fibrousness of the diet, resulting in a tendency (−5%) for a reduced daily gain and a lower energy efficiency (P < 0.05).