Dairy goat production in the semi-arid region: productive and reproductive analysis, and the influence of the adoption of hygienic practices on milk quality

ABSTRACT The aim of this study was to evaluate the productive and reproductive performance of dairy goat genotypes, as well as the influence of hygienic practices by farmers on the quality of goat milk. Productive and reproductive data of 81 Anglo Nubian and Alpine crossbred goats, as well as data on total milk production of goats over 100 days of lactation and partial production up to 56 days of lactation. Also, in natura milk samples from 160 properties in the region were evaluated. At the time of collection, a questionnaire was applied to diagnose goat milk production systems. Data from productive and reproductive performance were evaluated by Tukey test and descriptive analysis using the SPSS program. The herd presented a variation of the total milk production in lactation (TMP) from 267.40kg to 468.55kg, with lactation length ranging from 157 to 247 days, and average daily production between 1.43 and 1.89kg/day. Fertility rates were satisfactory, with the lowest rate being 76% and the highest 92%, with an average of 85.24% considering the six seasons of birth. The means of the gestation periods varied between 144 and 152 days. Regarding the sanitary characterization, 73% of farmers performed a cleaning of the room before and after milking. However, 94.8% of farmers did not eliminate the first jets of milk and only 29.2% used the screened mug test to identify clinical mastitis. Only 41% of farmers performed pre and post-dipping and 30.2% applied the iodine solution. Only 8.3% of farmers used disposable paper towels. However, 92% of producers still used fabric towel. It was also observed that 99% of the properties stored milk in buckets or cans without refrigeration. In the microbiological analysis, a small amount of milk samples (5.6%) was contaminated with Staphylococcus aureus, however the total coliform count was high. Regarding the somatic cell count, it was found that 86% of the properties presented values above one million cells per mL of sample. The study demonstrated the prevalence of several factors that contribute to the vulnerability of milk contamination in various stages of production such as milking and processing. Thus, the guidance and awareness of those responsible is extremely important to improve goat milk quality in the semi-arid region of Paraíba.摘要 本研究旨在评估奶山羊不同基因型的生产与繁殖性能，以及养殖户的卫生操作对山羊乳品质的影响。本研究收集了81只英奴比亚（Anglo Nubian）与阿尔卑斯（Alpine）杂交奶山羊的生产与繁殖数据，以及其泌乳100天以上的总产奶量和泌乳前56天的阶段性产奶量数据。此外，本研究还对该地区160个养殖点的生鲜乳样本进行了检测。样本采集期间，研究人员通过问卷调查对山羊乳生产系统进行了调研。研究采用SPSS统计软件，通过图基（Tukey）检验与描述性分析对生产与繁殖性能数据进行了统计分析。该群体的泌乳总产奶量（TMP）介于267.40kg至468.55kg之间，泌乳时长为157至247天，日均产奶量为1.43kg/天至1.89kg/天。受胎率表现良好，按6个产羔季统计，最低受胎率为76%，最高为92%，平均受胎率达85.24%。妊娠期均值介于144至152天之间。卫生特征调研结果显示，73%的养殖户会在挤奶前后对挤奶场所进行清洁。但94.8%的养殖户未进行弃奶操作（即挤掉初始乳流），仅29.2%的养殖户采用筛杯检测法来诊断临床乳腺炎。仅41%的养殖户实施了挤奶前后药浴操作，30.2%的养殖户使用了碘制剂溶液。仅8.3%的养殖户使用一次性纸巾，而92%的养殖户仍在使用织物毛巾。此外调研发现，99%的养殖点未采用冷藏方式，而是将乳样储存在桶或罐中。微生物分析结果显示，仅有5.6%的乳样被金黄色葡萄球菌（Staphylococcus aureus）污染，但总大肠菌群检出量较高。体细胞计数结果显示，86%的养殖点的乳样体细胞数超过100万个/mL。本研究表明，在挤奶与加工等多个生产环节中，存在多种易导致乳污染的风险因素。因此，对帕拉伊巴（Paraíba）半干旱地区的相关负责人开展指导与宣传教育，对提升山羊乳品质至关重要。