Mastitis, an infection of the mammary gland, is the most common and expensive animal health problem for the dairy industry and affects every dairy farm to some degree. This disease complex is painful for dairy cows, increases the on-farm use of antibiotics, presents a threat to milk quality and is a waste of time, money and milk production. Each year, the dairy industry loses as much as a billion dollars to mastitis. Many cows will experience mastitis at least once during a lactation cycle and some animals will develop recurring mastitis episodes in a single mammary quarter. These mastitic quarters can be difficult to manage during the lactation cycle. Cessation of production in the quarter while continuing to milk the other three can be a beneficial management decision in this scenario. However, the current methods available for cessation of lactation in a single quarter are limited. This study investigated the use of casein hydrolysate as a non-antibiotic option for causing cessation of lactation in a quarter. From this preliminary study we were able to apply our results to another aspect of mastitis prevention, which is the routine use of intramammary antibiotics at the end of the lactation cycle. This management practice is known as dry treatment and is a standard practice in the dairy industry with many years of proven efficacy against clearing infections present at the end of the lactation cycle. Increasing pressure from consumers to decrease antibiotic use in food production animals has caused this practice to come under scrutiny. This secondary study investigated the use of casein hydrolysates as a nonantibiotic alternative to standard antibiotic dry cow treatment. Overall, these studies demonstrated that casein hydrolysate has some efficacy in inducing mammary involution of a single quarter mid-lactation and also potentially as an alternative dry cow treatment. None of the animals treated in these studies displayed any symptoms of pain or discomfort, and all treated quarters resumed milk production after the next calving. Additionally, all antimicrobial milk tests on treated animals were negative. Casein hydrolysates may be a useful management tool for milk quality and animal health within the dairy industry.

A primary emulsion with whey protein isolate (WPI) and hexanoic acid was prepared, and chitosan (Ch) (0.01%, 0.02%, and 0.03%) was added to evaluate its impact on particle size distribution of the emulsion. NaCl (0, 20, 40, and 80 mM) was added to increase ionic interactions to stabilize the multilayer emulsion. Lecithin (0.5%, 1%, 2%, 3 %, w/v) was mixed with the primary emulsion in order to form a multilayer, and casein hydrolysate (CH) was used to stabilize the tertiary emulsion system without the use of NaCl for 28 d at 4 °C. Stable O/W nanoemulsions were generated for use as nano-vesicular vehicles (NVV) to carry Curcumin (CU). Two important variables, (1) addition of casein hydrolysate (CH) (1:50, w/w WPI) and, (2) use of high pressure (140 and 210 MPa), were studied for their effect on the stabilization of monodispersed NVV and persistence of antioxidant activity of the CU as cargo in the NVV throughout storage. Addition of CH reduced nano-particle size and increased emulsion stability with UHPH pressure. The nanoparticle distribution was not changed by the addition of CU. Addition of casein hydrolysate reduced particle size as well as enhanced the positive functional properties of the NVV. Similar trends were observed in zeta-potential, surface energy, contact angle and antioxidant efficacy of the NVV, both with and without CU when UHPH was applied. The effect of Ultraviolet (UV) radiation (254 nm) on the stability of O/W nanoemulsion systems was investigated. A nano vesicular vehicle (NVV) was generated using ultra-high pressure homogenization (UHPH) that was stabilized using whey protein isolate (WPI) (1%, w/v), Tween 20 (20% w/w WPI) and casein hydrolysate (CH) (1:50 of WPI, w/w). Coarse emulsions were prepared by blending for three min. The coarse emulsion was exposed to UV radiation (0-60 min), followed by a single-pass of UHPH at 140 and 210 MPa. The UHPH treated NVV-CU had greater (P<0.05) short and long term antioxidant properties. After 28 d of storage, the CU-NVV treated at 210 MPa retained 7.0 and 1.4% greater AA and AP, respectively, when compared to the unpressurized CU-NVV.