Agriculture and Agri-Food Canada

About: Agriculture and Agri-Food Canada is a facility organization based out in Ottawa, Ontario, Canada. It is known for research contribution in the topics: Population & Soil water. The organization has 10921 authors who have published 21332 publications receiving 748193 citations. The organization is also known as: Department of Agriculture and Agri-Food.

Nutritional, hormonal, and environmental effects on colostrum in sows.

Abstract: It is widely recognized that an early and high intake of colostrum is a major determinant of piglet survival during the early suckling period. The production of colostrum, however, is very variable among sows and the factors affecting this variability are not well known. Factors such as number of parity and genotype do seem to influence colostrum yield and composition. The endocrine status of the sow also affects the process of colostrogenesis and changes in the sow endocrine status can have an impact on quantity and quality of colostrum produced. Indeed, induction of parturition seems to play a role. Nutrition is undoubtedly a major factor that could be used as a tool to alter colostrum composition, with fat content being the most affected. Feed ingredients, such as yeast extracts and fermented liquid feed, were recently shown to alter colostrum composition, yet more research is needed to substantiate these effects. Very few data are available on the influence of environment on colostrum production; results suggest that heat stress has negative effects on colostrum composition. Considering the importance of colostrum for the survival, growth, and immune resistance of piglets, it is obvious that research on the development of new management systems is necessary to improve yield and composition of colostrum.

Fresh, Stockpiled, and Composted Beef Cattle Feedlot Manure

Abstract: The fate of manure nutrients in beef cattle () feedlots is influenced by handling treatment, yet few data are available in western Canada comparing traditional practices (fresh handling, stockpiling) with newer ones (composting). This study examined the influence of handling treatment (fresh, stockpiled, or composted) on nutrient levels and mass balance estimates of feedlot manure at Lethbridge, Alberta, and Brandon, Manitoba. Total carbon (TC) concentration of compost (161 kg Mg) was lower (< 0.001) than stockpiled (248 kg Mg), which was in turn lower (< 0.001) than fresh manure (314 kg Mg). Total nitrogen (TN) concentration was not affected by handling treatment while total phosphorus (TP) concentration increased with composting at Lethbridge. The percent inorganic nitrogen (PIN) was lower (< 0.01) for compost (5.1%) than both fresh (24.7%) and stockpiled (28.9%) manure. Composting led to higher (< 0.05) dry matter (DM) losses (39.8%) compared to stockpiling (22.5%) and higher (< 0.05) total mass (water + DM) losses (65.6 vs. 35.2%). Carbon (C) losses were higher (< 0.01) with composting (66.9% of initial) than with stockpiling (37.5%), as were nitrogen (N) losses (46.3 vs. 22.5%, < 0.05). Composting allowed transport of two times as much P as fresh manure and 1.4 times as much P as stockpiled manure (< 0.001) on an “as is” basis. Our study looked at one aspect of manure management (i.e., handling treatment effects on nutrient concentrations and mass balance estimates) and, as such, should be viewed as one component in the larger context of a life cycle assessment.

Evaluation of some indices of potentially mineralizable nitrogen in soil

Abstract: A series of soil N mineralization indices were evaluated using 153 samples chosen from arable fields representing a wide range of soil types, management practices, and climatic zones. These indices were compared against potentially mineralizable N (No) determined by aerobic incubation at 25°C for 24 wk. Three different pools of mineralizable N were recognized: Pool I, the mineralization flush on rewetting in the first 2 wk; Pool II, gross N mineralization in the next 22 wk; and Pool III, the potentially mineralizable N, predicted from the fitted curve, that did not mineralize during the incubation period. Pool I was highly correlated with CaCl 2 -N, KCI-NH 4 , and KCl-NO 3 , which extract soil mineral N. Pool III was significantly correlated with ultraviolet absorbance of NaHCO 3 extract at 205 and 260 nm (NaHCO 3 -205 and -260), Illinois soil N test, NaOH direct-distillation N, and hot KCl-NH 4 , which mostly extract hydrolyzable organic N. All indices except the mineral N based methods, phosphate-borate buffer method, and microbial biomass C were significantly related to N 0 , which includes both Pools II and III. The NaHCO 3 -260, NaOH direct-distillation N, and Illinois soil N test had the highest correlations with No (r2 = 0.74, 0.61, and 0. 51, respectively). Total organic C and N represent long-term changes in N 0 and were almost as effective in predicting N 0 as the other indices (r 2 = 0.60 and 0.67, respectively); however, they would be expected to be less sensitive to short-term changes in N 0 due to changes in soil management practices and history.