Comparative evaluation of non-genetic factors affecting milk yield and composition of Red Dane and Jersey cattle in Zimbabwe

A study was carried out to evaluate non genetic factors affecting milk yield and milk composition in Zimbabwean Red Dane and Jersey cattle cattle. A total of 1004 and 10 986 unedited Red Dane and Jersey 305-day lactation records respectively, were obtained from Livestock Identification Trust (LIT) containing 22 herds (1 Red Dane herd and 21 Jersey herds), with Red Dane calving in the period 2004 to 2009 (giving year of birth from 1998 to 2007) and Jersey cows calving in the period 1996 to 2008 (giving year of birth from 1994 to 2005). The General Linear Model (GLM) procedure of the Statistical Analysis System (SAS, 2004) version 9.1.3 was used to determine the genetic parameters and environmental factors. Calving interval, month of calving, parity and quadratic effects of age at calving fitted as covariates significantly (P < 0.0001) affected the milk, fat and protein yields. Milk, fat and protein yields obtained increased with an increase in calving interval. There was a linear and quadratic relationship between the production traits and age at calving of the Jersey cattle implying that milk, fat and protein yields increase with age of the animal. It is thus important to preadjust data for these environmental factors when carrying out genetic evaluations of production traits in dairy cattle

Efforts to improve Zimbabwe communal grazing areas: a review

The management of rangelands over the past decade in Zimbabwe has been on the decline. This has resulted in degraded and depleted communal rangelands. A number of recommendations by various government departments, researchers and non-governmental organisations have been implemented. These focused on improving communal grazing areas throughout the country. Notable examples include the livestock destocking policy, introduction of grazing schemes, improved forage grasses, veld legume reinforcement and agro-forestry technology. However, success in improving communal grazing areas has been limited, with forage productivity in communal areas declining, soils still eroding, as well as loss of flora and fauna diversity. The objectives of this paper are to review factors limiting efforts to improve communal grazing areas, constraints to adoption of rangeland technologies necessary to achieve desired plant community for livestock production, and present recommendations to overcome the challenges. The review concludes that there has been limited farmer participation in efforts to improve communal grazing areas and livestock productivity, thus the low adoption of technologies to improve the grazing areas. It is therefore recommended to use participatory approach methodologies to assist communal livestock farmers to improve their grazing areas.Keywords: adoption, challenges, rangeland improvement technologie