Influence of the Use of Milk Replacers on Carcass Characteristics of Suckling Kids from Eight Spanish Goat Breeds

Since goat milk has a higher value than kid meat in Europe, some farmers rear kids with milk replacers, although some studies have stated that kids raised on natural milk yield higher-quality carcasses. Our previous studies showed some interactions between breed and rearing system on carcass and meat quality. This study evaluated the influence of the use of milk replacers on several carcass characteristics of suckling kids from eight Spanish goat breeds (Florida, Cabra del Guadarrama, Majorera, Palmera, Payoya, Retinta, Tinerfeña, and Verata). A total of 246 kids fed milk replacer (MR) or natural milk (NM) were evaluated. Carcass, head, viscera, and kidney fat weights, as well as several carcass measurements (round perimeter, forelimb width, carcass length, forelimb length, and carcass compactness index), were registered. Forelimbs were dissected to study tissue composition. For all studied variables, interactions were found between rearing system and breed. In general, the MR rearing system increased the head and visceral weights, as well as the length measurements and muscle percentages. Conversely, the NM rearing system increased carcass compactness and resulted in higher fat contents, independent of the deposit. The choice of one or another rearing system should be made according to the needs of the target market.

Conservation of criollo livestock in the United States: challenges and solutions

Conservation of criollo breeds in the USA provides for the survival of unique genetic resources that remain productive in challenging environments. Conservation is difficult because most criollo breeds are local and have no formal organization of breeders. Successful conservation has depended on establishing accurate breed definitions and investigations of phenotype, history, and genetics. Organization of breeders and of breeding has been essential for the final success of conservation efforts. Each specific breed has met its own unique challenges. Among cattle breeds, Texas Longhorns needed an accurate breed definition as well as genetic investigations, whereas Florida Crackers needed organization. Spanish goats required definition, organization, and research into their productive potential. This has led to the Spanish goat now being secure as a popular choice for extensive production of goat meat. Navajo Churro sheep are maintained by ongoing phenotypic evaluation at each generation and careful attention to the frequency of phenotypic characteristics within the population. The other criollo sheep breeds in the USA (Louisiana, Gulf Coast, and Florida) have benefitted from genetic studies that demonstrate differences among the breeds and guide conservation of each of these related types in isolation one from the others. The organization of criollo swine has lagged behind the others, with the Duroc standing out as an exception that has become one of the main breeds in commercial hog production.

Phenotypic Characterization of Encephalitis and Immune Response in the Brains of Lambs Experimentally Infected with Spanish Goat Encephalitis Virus

Spanish goat encephalitis virus (SGEV), a novel subtype of tick-borne flavivirus closely related to louping ill virus, causes a neurological disease in experimentally infected goats and lambs. Here, the distribution of microglia, T and B lymphocytes, and astrocytes was determined in the encephalon and spinal cord of eight Assaf lambs subcutaneously infected with SGEV. Cells were identified based on immunohistochemical staining against Iba1 (microglia), CD3 (T lymphocytes), CD20 (B lymphocytes), and glial fibrillary acidic protein (astrocytes). In glial foci and perivascular cuffing areas, microglia were the most abundant cell type (45.4% of immunostained cells), followed by T lymphocytes (18.6%) and B lymphocytes (4.4%). Thalamus, hypothalamus, corpus callosum, and medulla oblongata contained the largest areas occupied by glial foci. Reactive astrogliosis occurred to a greater extent in the lumbosacral spinal cord than in other regions of the central nervous system. Lesions were more frequent on the side of the animal experimentally infected with the virus. Lesions were more severe in lambs than in goats, suggesting that lambs may be more susceptible to SGEV, which may be due to species differences or to interindividual differences in the immune response, rather than to differences in the relative proportions of immune cells. Larger studies that monitor natural or experimental infections may help clarify local immune responses to this flavivirus subtype in the central nervous system.