Lactococcus lactis is a dairy culture bacterium widely used in dairy products that contain salt (NaCl) such as cheese and salted butter. Osmotic conditions generally hinder the growth of both pathogen and desirable bacteria. It has been observed that many stress-induced proteins are produced after exposure to an environmental stress protecting the cell against other stresses since the first exposure starts the defense mechanisms of the cells creating an effect of cross-protection. If salt tolerance is enhanced in desirable bacteria they would survive better in salty environments. The objective of this study was to evaluate the salt tolerance of Lactococcus lactis R-604 after exposure of various stress conditions. The culture was subjected to 10% v/v ethanol for 30 minutes, 15 mM of hydrogen peroxide for 30 minutes, mild heat at 52°C for 30 minutes and UV light (245 nm) for 5 minutes. The culture was also subjected to starvation (no lactose in M17 broth) for 24 hours or prior osmotic adaption (3% w/v NaCl in M17 broth) for 24 h aerobically at 30°C. A control was run without any stress under the same conditions of each experiment. An initial concentration of 7 log CFUs/mL was used for all treatments. Growth was determined under 5 concentrations of NaCl (0, 1, 3, 5 and 7% w/v). Plating was done every 24 h for 5 days in M17 agar with 0.5% w/v of lactose and incubated aerobically at 30°C for 48 hours. Salt tolerance was enhanced after mild heat or ethanol exposure at 5% w/v NaCl on days 3, 4 and 5. Salt tolerance was also enhance after hydrogen peroxide stress at 5% w/v NaCl on days 4 and 5 and after 24 hours of lactose starvation at 3% w/v on day 3. L. lactis R-604 was not negatively affected by any of the stress conditions applied at salt concentrations of 0, 1 and 3% w/v NaCl. The culture was able to grow in 3% NaCl or no lactose after 24 hours and these stress conditions did not affect its salt tolerance. Growth was maintained at 7% w/v NaCl regardless the stress conditions, however combination of ethanol or hydrogen peroxide at 7% w/v NaCl reduced growth of L. lactis R-604.

Gastrointestinal nematode (GIN) parasites cause extensive damage to small ruminants, and Haemonchus contortus is a major concern to production worldwide. With the development of GIN resistance to anthelmintics, alternative strategies for control are needed. The major component of this study compared two strategies for effect on animal health and changes in GIN population. One flock of ewes and lambs (Strategy 1, S1) employed targeted selective treatment (TST) with an anthelmintic based on FAMACHA score, and one flock (Strategy 2, S2) employed sericea lespedeza (SL) supplement feeding and TST with copper oxide wire particles (COWP) based on FAMACHA score. S1 ewes/lambs were supplement fed a concentrate ration and were dewormed with levamisole/albendazole combination when FAMACHA© was 4/5. The S2 ewes/lambs were supplemented with SL pellets and were dewormed with COWP when FAMACHA© was 4/5. FEC for S2 ewes/lambs remained consistently lower and PVC higher than for the S1 ewes/lambs. There were fewer dewormings for S2 lambs than S1 lambs and no ewes needed to be dewormed. Weight gain for S2 lambs was consistently less than S1 lambs. It was also noted that S2 lambs had less coccidia than S1 lambs. To follow up on a possible reason for the poorer production of S2 lambs, a trace mineral panel was done on the ewes/lambs and it was noted that S2 animals were very deficient in molybdenum (Mo). A study was done to evaluate Mo supplementation on weight gain and results indicated a slight improvement. Upon supplementation with Mo, Mn, Se and Zn serum concentrations of all increased but did not achieve normal values nor did it impact weight. S2 lambs had fewer coccidia counts than S1 lambs. Control lambs received Purina® Honor® Show Lamb and treatment lambs were fed SL pellets. Lambs were inoculated with 50,000 oocyst over a 3 day period at the beginning of the study. Lambs in the treatment group had lower FEC and coccidian counts than the lambs in the control group. SL was effective in the prevention and control of coccidiosis as well as in reducing GIN infection.

The objective of this research was to determine differences in carcass evaluation, yield, and meat quality from representative fresh domestic (FSD), frozen domestic (FZD), and frozen imported Australian (FIA) goat carcass sides (n=30 from each source). The U.S. carcasses were split into sides and the right side frozen and stored for 6 weeks. Left sides were fabricated into standardized primal cuts. After frozen storage, right sides and FIA carcasses were thawed for 3 days at 4°C. Three experiments were conducted on the carcass traits and meat yields, quality differences in leg cut, and differences in loin and racks across freezing and packaging treatments. Domestic carcasses were heavier (P<0.05) with more (P<0.05) external fat, but carcass conformation and lean flank color were not different than imported Australian goat carcasses. Australian carcasses had less waste and higher trimmed primal loin, rack, leg, shank, and shoulder yields as % of carcass weight than domestic sides. Freezing and thawing changed the percentages of cuts, but FIA carcasses had higher (P<0.05) yields of lean trimmed primal cuts and FIA legs had higher (P<0.05) drip, cook losses, and water binding, but lower (P<0.05) color values than the FZD legs or FSD legs. With paired t-tests, FZD legs had higher (P<0.05) drip and cook losses and lower (P<0.05) color values than FSD legs. FZD and FIA chops had higher (P<0.05) drip and cook losses than FSD. Freezing lowered (P<0.05) color values of chops, however, packaging with 0.5% CO increased (P<0.05) a* and chroma values of frozen meat over that of fresh goat meat before packaging. Vacuum packaging of goat chops increased (P<0.05) drip and chops in overwrap packaging had the lowest (P<0.05) color values. Packaging did not (P>0.05) affect Warner-Bratzler shear values. FSD chops had higher (P<0.05) shear force values than FZD, which were higher than FIA. Loin chops had greater (P<0.05) drip and cook losses than rib chops. Rib chops were found to have higher (P<0.05) color values both pre and post package and lower (P<0.05) shear force values when compared to loin chops.

One of the most significant threats to the well-being and performance of grazing livestock are gastrointestinal nematode (GIN) parasitic infections. Allowing a large GIN burden to manifest can cause a significant cost in terms of productivity in grazing cattle. Beef producers commonly rely greatly on the efficacy of broad-spectrum anthelmintics, to not only kill resident worms but to also prevent the establishment of ingested infective stage larvae (L3) for a period following treatment. Eprinomectin (LONGRANGE®, E-LR) is the first extended-release injectable cattle dewormer that claims to provide cattle producers season-long persistent parasite control for 100 to 150 d in a single dose, dependent on parasite species. This in turn, improves nutritional efficiency. The purpose of this study is to evaluate the efficacy of E-LR for controlling long-term GIN infections in nursing calves. E-LR was compared to the traditional anthelmintic fenbendazole (Panacur®, F-P). Four groups of nursing calves (with their dams) grazed separate pastures and pastures were rotated after each sampling date to ensure equal parasitic pasture exposure. Two groups were treated with E-LR and two groups were treated with F-P. Calves were weighed at 28 d intervals and fecal samples were collected on d 0, 14, 28, 56, 84, and 112. Results indicated E-LR was effective in providing long term parasite control. There was no significant (p < 0.05) difference in the FEC between F-P and E-LR treated animals on d 14, showing that both were efficient at initially killing GIN. Significant differences in FEC between treatments started to show by d 56. On d 56, there was an increase in FEC in calves treated with F-P which continued to increase throughout the rest of the study. The E-LR treated animals had only slightly increased FEC for the rest of the study which indicated prolonged GIN control.

The study of cooperation has been crucial to research on the evolution of social living in human and animal societies. Grooming interactions have been used as model to investigate the exchange of services in animals. Using both established and novel methodologies, this thesis examines grooming interactions and cooperation in two populations of wild Barbary macaques living in the Middle Atlas Mountains of Morocco. It is important to have a comprehensive idea of the costs and benefits of grooming interactions, and of the effect of grooming interactions on the anxiety of the grooming partners. This thesis showed that, contrary to previous studies, anxiety increased after grooming interactions in both the donor and recipient. This highlights the need to further investigate the link between grooming and emotions. Individuals may also affect the grooming interactions of other group members. This thesis showed that individuals benefit from disrupting grooming interactions of group members by gaining grooming opportunities for themselves and by stopping the group members from grooming each other, although grooming disruptions may be risky. Monkeys may affect others’ grooming interactions to favour their own social and dominance positions. A key aspect of this thesis was also to assess whether grooming is reciprocated in the short-term and which type of reciprocity (i.e. direct, indirect and generalised) play a role in the exchanges of grooming. This study showed that direct but not indirect and generalised reciprocity play a role in the exchange of grooming. While there is a wide range of evidence that direct reciprocity plays a role in the exchange of services in animals, there is little evidence of indirect and generalised reciprocity. Additionally to exchanging grooming for grooming, animals also exchange grooming for other services such as tolerance around food resource and support during agonistic interactions. In this thesis, no evidence of short-term contingency between the exchange of grooming and food tolerance was found. The exchanges of services may be little affected by recent single events, and mechanisms involving an emotional mediation based on long-term social bonds between partners may play a more important role. The capacity to make effective choices among potential social partners is an important social skill, as choosing the best available partner improves the chances to establish successful cooperative interactions. This thesis highlighted, to some extents, the importance of factors such as tolerance and relationship quality between partners, in the performances of individuals and their choice of partners to solve a cooperative task. Tolerant relationships may have been a prerequisite for the evolution of cognitively complex cooperation. Testing a comprehensive framework of predictions, this thesis brings novel contributions to the understanding of grooming interactions and cooperation in wild Barbary macaques.

Vitrification is the latest technique used in cryopreservation, the ability to utilize this method with oocytes and embryos has become a valuable system. Vitrification has been successful with bovine embryos and oocytes but is far from optimal. Following cryopreservation storage discarding embryos can cause ethical issues, and mature oocytes have fragile organelles that can be detrimentally affected by ice crystal formation during freezing. Immature oocytes have not formed some of these temperature sensitive microfilaments and can circumvent these detrimental effects. The common intracellular cryoprotective agents are dimethyl sulfoxide, glycerol and ethylene glycol. Different combination of these agents have been reported for vitrification of oocytes. The overall objective of this experiment was to determine if immature and mature cumulus cell complexes vitrified in solutions of dimethyl sulfoxide or glycerol in combination with ethylene glycol would be competent to produce pronuclei following thawing and in vitro fertilization. Two experiments evaluated two cryoprotectant solutions and their ability to fertilize bovine cumulus cell complexed oocytes (n=400). The first study used DMSO and glycerol containing vitrification solution with immature bovine oocytes (n=200) followed by IVM and IVF with an end point of pronuclei formation to indicate fertilization. The second used DMSO and glycerol containing vitrification solutions with mature bovine oocytes (n=200) followed by IVF. We found that vitrifying immature oocytes with DMSO or Glycerol containing solutions prior to IVF resulted in higher fertilization for DMSO P<.01. Vitrifying mature oocytes with DMSO or glycerol containing also resulted in higher fertilization for DMSO solution P<.05. These results suggest that DMSO may be the more appropriate choice when used in combination with ethylene glycol for vitrification of immature and mature oocytes.

Twenty-four male Holstein calves (BW = 38.78 ± 7.26 Kg) were used to evaluate the effects of commercially available or farm mixed starter on animal performance, blood metabolites, and rumen health. Calves were randomly assigned to one of two treatments which included: commercial calf starter (minimum 20% CP; CCS) and starter of similar nutrient content but hand mixed on farm (FMS). Calves were offered treatments ad libitum on days 4 through 84. Milk replacer (MR) was offered beginning on day 4. On day 42, MR was reduced to once daily to decrease intake by 50%. On day 49 calves were weaned but remained in hutches for the remainder of the 84 d trial. Body weight (BW), hip height, withers height, hip width, and body length were recorded weekly, and grain and milk replacer intakes were measured twice daily. Rumen fluid and blood samples were collected every two weeks beginning on week 2 for analysis of ruminal pH, ammonia (NH3), volatile fatty acids (VFA), plasma urea nitrogen (PUN), plasma glucose, and â-hydroxybutyrate (BHBA). There was a treatment by week interaction (P < 0.05) for BW, starter intake and PUN. Postweaning BW was greater (P < 0.05) for calves fed FMS. Calves fed FMS had higher (P < 0.05) overall ADG. However, there were no differences (P > 0.05) on ADG before weaning. There were no treatment effects (P > 0.05) on structural growth variables, feed efficiency, and fecal scores. Calves fed FMS had greater (P < 0.05) starter intake. There were no treatment effects (P > 0.05) on total VFA concentrations, VFA molar percentages, glucose, and BHBA. Ruminal pH was higher (P < 0.05) for calves fed FMS while ruminal NH3 concentrations were greater (P = 0.03) for calves fed CCS. Calves fed CCS had greater (P < 0.05) PUN concentrations. These data suggest that farm mixed diets can equal commercial calf diets for general performance and rumen development when calf starter meets all the nutrient necessary for normal growth and is properly mixed.

Feeding laying hens or broiler breeder hens organic sources of trace minerals can improve egg quality, especially as related to shell quality. The objectives of this research were to evaluate the effect of increasing laying hen dietary zinc (Zn) levels on the content of Zn and other minerals in eggs (boron (Bo), iron (Fe), and calcium (Ca)), and to evaluate the effect of feeding increasing Zn, manganese (Mn) and copper (Cu) levels from inorganic (ITM) and organic (OTM) sources on egg quality and yolk content of Zn, Mn, and Cu. In the first experiment, a total of 64 (48 weeks of age) commercial hens (Hy-Line W-36) were allotted to one of four treatments diets on day 0. There were four replicates with four hens per replicate. The dietary treatments were: 1) corn-soybean meal (C-SBM) with no added Zn (25 mg/kg total Zn from feeding ingredients), 2) C-SBM with 50 mg/kg added Zn, 3) C-SBM with 100 mg/kg added Zn, and 4) C-SBM with 150 added mg/kg Zn. The inorganic source of Zn was ZnSO4. The trial lasted 30 days. In the second trial, 600 Hy-Line W-36 hens at 26 weeks of age were used. Hens were allotted to one of five treatment diets on day 0 of the trial. A total of 10 replicates with 12 hens per replicate were used. The dietary treatments were: 1) Control - no supplementation of Zn, Mn, or Cu, 2) Zn, Mn, and Cu supplemented at 80-90-8 mg/kg from ITM, 3) Zn, Mn, and Cu supplemented at 80-90-8 mg/kg from ITM+OTM, 4) Zn, Mn, and Cu supplemented at 160-175-16 mg/kg from ITM, and 5) Zn, Mn, and Cu supplemented at 160-175-16 mg/kg from ITM+OTM. The trial lasted 84 days. The response criteria were egg weight, specific gravity, egg shell thickness, egg shell weight, albumen height, yolk height and width, Haugh units, yolk index, feed intake and feed conversion. Data were collected on three consecutive days at the end of each 28 day period. On the second day of each three day collection period, three yolks per replicate were collected and stored for analysis of Zn, Mn, and Cu content. In the first experiment, hens fed more than 100 mg/kg added Zn had reduced egg production and egg mass. Zinc content in the egg yolk was increased 23% with 150 mg/kg added Zn. In the second experiment there was no effect (P>0.05) of dietary treatment on egg production. During the first 28 day collection period, yolk Zn and Mn were highest (P<0.01) for hens fed the 160-175-16 mg/kg from ITM+OTM. In the third 28 day collection period, albumen height was highest (P<0.05) in eggs laid by hens fed the control diet and similar for hens fed all other treatment diets. Egg weight and egg mass were not affected by increasing dietary inclusion of Zn, Mn, and Cu. Feed intake was improved for the first 28 day collection period. Egg/kg of feed was increased when hens were fed the 80-90-8 mg/kg from ITM+OTM. Thus, Zn content of the egg yolk may be increased by the inclusion of ITM+OTM at rates above their requirement in layer diets.

The American Veterinary Medical Association has stated the importance of minimizing pain associated with dehorning to limit the amount of distress and changes in the animals behavior and physiological states (AVMA, 2014b). The following studies aim to determine the effect of timing of lidocaine administration on physiological responses in calves after dehorning. The first study compared cortisol and substance P levels in calves dehorned immediately after administration of lidocaine and meloxicam, calves dehorned 10 minutes after the administration of lidocaine and meloxicam, and calves that were administered lidocaine and meloxicam and not dehorned. It was concluded waiting 10 minutes after administration of lidocaine and meloxicam to dehorn calves provided no benefits, as it did not reduce plasma cortisol and substance P compared to other treatment groups. The second follow up study compared cortisol and adrenocorticotropic hormone (ACTH) levels in calves dehorned immediately compared to calves dehorned 10 minutes after the administration of lidocaine alone, calves dehorned without lidocaine, and calves administered lidocaine but not dehorned. Waiting 10 minutes to dehorn calves after lidocaine administration may provide some benefits in reducing plasma ACTH and cortisol. Calves dehorned after a 10-minute waiting period had lower peak plasma ACTH levels and reached pretreatment levels for both plasma ACTH and cortisol quicker than the other treatment groups that were dehorned. However, differences observed in ACTH dissipate in 5 minutes and all calves reached baseline plasma cortisol levels within an hour of dehorning.

A series of experiments studied the possible role for prolactin in the spring-time recrudescence of ovarian activity in mares. The first experiment was based on cabergoline administration to seasonally anovulatory mares to prevent the seasonal rise in endogenous plasma prolactin to assess whether reduced prolactin altered onset of ovarian activity or first ovulation. Although prolactin concentrations were reduced, basal prolactin concentrations recovered from suppression by the time of the next injection (10 days later), even though low-dose sulpiride stimulation of prolactin was still suppressed by 85%. The subsequent experiment tested whether season affected the duration and degree of suppression produced by a standard dose of cabergoline. Mares were administered cabergoline at 1.5 mg/500 kg body weight in March, June, September, and December. Duration of suppression was affected little by month of assessment. Follow-up assessments with either low dose sulpiride (July) or thyrotropin releasing hormone (October) challenges after administration of 5 mg cabergoline indicated that basal prolactin concentrations always rebounded earlier than secretagogue-induced secretion. The third experiment studied possible physical and hormonal characteristics of seasonally anovulatory mares that might affect their response to a combined estradiol and sulpiride treatment for inducing ovulation in winter. All mares received 50 mg of estradiol cypionate (ECP) followed by 3 g of sulpiride. Factors that were commonly associated with early-induced ovulation were: adequate body condition, elevated plasma concentrations of leptin and insulin, and a greater LH response to secretagogue prior to the start of the experiment. The final experiment studied the hormonal production aspects of the first pre-ovulatory follicle of the breeding season in seasonally anovulatory mares treated with ECP followed by injections of sulpiride 5 and 12 days later, or ECP plus vehicle (controls), beginning in January. Date to first 35-mm follicle was advanced in sulpiride-treated mares. It was concluded that early-induced follicles are equally as competent in terms of steroid production and ability to respond to circulating LH as pre-ovulatory follicles occurring naturally in spring. These experiments support the model in which an increase in circulating prolactin during winter can hasten follicular growth and advance the date to first ovulation in most mares.