Nubian boer cross weight chart7/12/2023 The Spanish goat is a landrace genotype that has evolved from centuries of natural selection in the US. It has become the most popular meat goat in the US since its introduction in the 1990s. There are 3 primary meat goat breeds managed in the US. Evaluation of traits that indicate female fitness is often not considered when comparing meat goat breed options. Breed selection and utilization are important in enterprise success, particularly in the area of doe performance. Genetics is often overlooked aspect of herd health management. Morantel tartrate is available as a feed additive however, feed is not viewed as a preferred delivery method for anthelmintics in goat herds. Widespread endoparasite resistance to bendazoles is evident in goat herds. However, only four anthelmintics are FDA-approved for goats (three bendazole products and morantel tartrate). For example, internal parasitism is widely recognized as a primary health risk to sustainable goat production. In the US, maintaining adequate health in meat goats is a greater challenge than in other livestock classes because of the relative lack of medications approved for use in goats by the US Food and Drug Administration (FDA). Published studies of longevity in goats are few and limited to dairy herds. Females with extended productive lives would be expected to generate a greater lifetime amount of marketable product (e.g., offspring, milk, etc.) with associated herd-wide benefits. Females with short productive lives are costly in terms of lost production at peak performance ages, biological and economical costs associated with young replacements, medical treatments associated with subsequent illness culls, and lost salvage value in cases of death. Longevity of breeding females has an economic impact on commercial meat animal production systems. Functional longevity (i.e., length of productive life) is defined by the ability of animals to avoid death or culling as a result of illness or reproductive failure. Stayability is an indicator of longevity that measures the proportion of animals remaining productive to a fixed time endpoint. Kiko and Spanish does did not differ for longevity and lifetime performance indicators. Poor health was the primary driver of does exiting the herd. Conclusionīoer does had low stayability and cumulative kid production rates compared with Kiko and Spanish does. Boer does had lower ( P < 0.01) total number of kids weaned and cumulative weight weaned through each stayability endpoint compared with Kiko and Spanish. Under the alternative protocol, over 50% of Boer does failed to complete 2 years, whereas over 50% of Kiko and Spanish does successfully completed 4 years. Boer does had lower stayability rates ( P < 0.01) at each year endpoint for both culling protocols. Boer does had greater survival declines ( P < 0.01) from 2 to 6 years of herd life compared with Kiko and Spanish under both culling protocols. Reproductive failure represented 51% of doe exits under the alternative culling protocol. Most (82%) doe exits were illness-related under the actual culling method. Kid production traits analyzed across herd life were the total number of kids weaned and cumulative kid weight weaned to the 2-, 3-, and 5-year stayability endpoints. An alternative culling protocol removed doe records after the first failure to wean a kid. The actual culling practice removed does after two failures to wean a kid. Survival curves were analyzed for 2 culling methods. Does had the chance to complete 2 to 6 production years. The herd was managed on humid subtropical pasture. Resultsīoer (n = 132), Kiko (n = 92) and Spanish (n = 79) does were evaluated for longevity trends and cumulative kid production. The purpose of this study was to determine if breed of meat goat influences breeding doe survival rates and cumulative reproductive performance under semi-intensive management. This is a trait of economic relevance in commercial small ruminant breeding herds as it affects lifetime reproductive output. Longevity is the amount of time breeding females stay active in a herd by avoiding death or culling because of illness or reproductive failure.
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