Different protocols for piglet creep feeding in the farrowing stage and residual effects in the nursery phase.

This study was aimed at the effects of different Creep-feeding protocols on piglet performance and its residual effects during the nursery phase. Experimental design used was five groups: WC (without creep); DCF (dry creep feeding); WCF (wet creep feeding); LD (additional liquid creep with automatic feed dispenser plus DCF); and LLF (additional liquid creep with linear feeder plus DCF). Ten litters per treatment were selected a total 50 sows and 645 piglets. During the first two weeks of lactation, the LD treatment (2.61 and 4.20 kg) promoted greater body weight (P <0.001) than the DCF (2.55 and 3.93 kg), (WFS) (2.43 and 3.69 kg) and LLF (2.50 and 4.00 kg) treatments, but did not differ from the WC treatment (2.68 and 4.09 kg). At weaning, the WC (5.22 kg), LD (5.32 kg) and LLF (5.27 kg) treatments gave higher body weights (P <0.001) when compared to the DCF (4.97 kg) and WCF (4.69 kg) treatments. We concluded that there was no change in the behavior of the piglets, and the use of dry feed with liquid supplements did not improve weight gain. The different creep feeding systems did not influence the weight and performance of the piglets in the nursery phase.

The addition of residue from pruning of yerba mate (Ilex paraguariensis) in laying hens modulates fatty acid profile and incorporates chlorogenic acid in the egg.

This study aimed to determine whether the addition of Ilex paraguariensis residue to the basal diet of laying hens improves bird health, production, fatty acids, egg quality, and transfer of chlorogenic acids to the egg. One hundred twenty birds of the Hy-line lineage were used, divided into five groups with six replicates and four birds per replicate, as follows: T0 (control group, without IPPR supplementation), T0.5 (basal diet plus 0.5% of IPPR), T1 (basal diet plus 1% IPPR), T1.5 (basal diet plus 1.5% IPPR), and T2 (basal diet plus 2% IPPR), for two consecutive cycles of 21 days each. The productive performance of the birds, physicochemical composition of eggs, fatty acid profile, the concentration of chlorogenic acids in eggs, leukocyte count, serum biochemistry, oxidant and antioxidant status, total bacterial count in eggs, and feces were evaluated at 21 and 42 days of the experiment. The addition of IPPR to the birds' diet no-change eggs production and feed conversion. In the egg yolks of birds that consumed IPPR, there were chlorogenic acids. There was a reduction in the total bacterial count in the feces and eggshells of the birds that received 2% of the IPPR. IPPR intake also reflected a reduction in total saturated fatty acid levels and increased monounsaturated fatty acids. These findings suggest that IPPR is a compelling alternative for laying hens; however, its ingestion also has negative effects that are discussed in below. Chlorogenic acids in the egg are desirable, as these phenolics have nutraceutical effects in humans.

Microencapsulated phytogenic in dog feed modulates immune responses, oxidative status and reduces bacterial (Salmonella and Escherichia coli) counts in feces.

Improving the health and immunity of pets is a concern of the guardians, while maintaining the health of the animals directly impacts the owners' health and public health. The objective of this study was to produce a dog feed containing a microencapsulated phytogenic blend, as well as determine the impact of the additive on animal health and its intestinal microbiota. The composition included microencapsulated thymol, carvacrol, and cinnamaldehyde, at 300 mg/kg of feed. Ten male beagle dogs were divided into two groups, identified as follows: the control group (C; ingested the feed without the additive) and the treated group (T; consumed feed containing the phytogenic blend). The dogs received 300 g of feed/day divided into two meals. Greater neutrophil counts in group T and lymphocyte counts were observed at the end of the experiment, as well as levels of α2-globulins and γ-globulin, while ß1 and ß2-globulins levels were lower in group T. Serum nitrogen oxide levels were higher in group T. Levels of reactive oxygen species were lower in group T at days 30 and 45, unlike activity of glutathione peroxidase that was higher. We found less bacterial contamination in the feces of dogs in group T, i.e., total bacterial count, total coliform counts, and counts of Salmonella and Escherichia coli were lower on days 30 and 45. Phytogenic blend intake reduces bacterial counts in stool and improves antioxidant/oxidative status and immune responses.

Dietary supplementation with curcumin-loaded nanocapsules in lambs: Nanotechnology as a new tool for nutrition.

Curcumin-containing nanocapsule powder formulations have not been used in ruminant feed to date, despite the fact that curcumin is known to be a functional food additive. The objective of this study was to determine whether ethyl polymethacrylate (Eudragit L-100) nanocapsules loaded with curcumin (N-CU) would improve health and growth of lambs. Thirty-two male Lacaune lambs (body weight [BW] = 16 ± 0.99 kg; 45 d of age) were randomly assigned to 1 of 4 treatments: T0, T1, T2 and T4, representing supplementation of curcumin at 0, 1, 2, and 4 mg/kg concentrate, respectively. The animals in each treatment were allocated in 4 pens of 2 lambs each (8 lambs per treatment). The experiment lasted 17 d, with samples and measurements collected on d 0, 7, 12, and 17. The T2 lambs had greater average daily gain than T0 lambs. Regression analysis showed that the ideal dose of N-CU to enhance weight gain was 1.89 mg/kg concentrate. There were significant interactions (P < 0.05) between treatments × time for hematological variables, particularly for increases in erythrocytes (T2) and reductions in counts of leukocytes, neutrophils, and lymphocytes in T1 and T2. There were significant interactions between treatment × time for total protein, globulin, urea, and triglyceride levels. Stimulation of the antioxidant system was also observed. There were increased levels of non-protein thiols (NPSH), as well as increased activities of superoxide dismutase (SOD) and glutathione S-transferase (GST) in the supplemented animals. Levels of reactive oxygen species (ROS) were lower in the serum of supplemented lambs. In general, the 4 mg/kg dose had no positive effects on growth or health. This was an unexpected result, given the known properties of curcumin. Taken together, these findings suggest that addition of low concentrations of nanoencapsulated curcumin (T1 and T2) in lamb feed improves health, minimizing oxidative stress and generates anti-inflammatory effects that may have contributed indirectly to greater weight gain. Nanocapsules potentiate the effects of curcumin and may emerge as a new tool in animal nutrition.

Positive effects of biocholine powder dietary supplementation on milk production and quality, and antioxidant responses in lactating ewes: A new nutritional tool.

We determined whether the dietary supplementation with a commercial product (vegetable biocholine - VB) for Lacaune ewes at peak lactation would improve animal health and production as well as milk quality. We also determined the effects of VB as a feed additive. We used thirty Lacaune ewes at 30 days of lactation, allocated into three groups: T0 (control, without VB), T5 (5 g of VB/animal/day) and T10 (10 g of VB/animal/day). T10 sheep had greater milk yield during the experimental period. T10 ewes had also a significantly lower feed conversion ratio than the other groups. Total solids concentration of milk was higher in T10 than in the other groups on day 20. The somatic cell count in milk was lower in ewes that consumed VB in the highest dose (T10) than in the T0 and T5 in days 15 and 20. Lower levels of lipoperoxidation (LPO) and of reactive oxygen species (ROS) were observed in milk from ewes fed with the VB supplemented diet on day 20, associated with increased levels of total antioxidant capacity and superoxide dismutase activity in milk. In serum, we found that T5 and T10 animals had significantly higher levels of non-enzymatic antioxidants (non-protein thiols) associated with reduced LPO and ROS content. Higher levels of globulins were observed in T10 than in T0 sheep on day 20. These data suggest that VB dietary supplementation stimulates antioxidant responses and increases the concentration of globulins in a manner beneficial to sheep health. Milk production, feed conversion rate, and milk SCC were also improved.

Effects of biocholine powder supplementation in ewe lambs: Growth, rumen fermentation, antioxidant status, and metabolism.

The objective of this study was to evaluate the effects of biocholine powder (BP) added to the concentrate of ewe lambs on growth, rumen fermentation, antioxidant status, and metabolism. Forty-eight Lacaune lambs were divided 3 treatments: T0, T4, and T8, representing 0, 4, and 8 g of BP per animal/day added to the concentrate, respectively. The T4 and T8 lambs had greater average daily gain from d 0-75 (0.22, 0.25, and 0.26 kg/d for T0, T4 and T8, respectively). T4 and T8 lambs had higher methylene blue test results (indicating microbiological activity), and the higher effects were detected for T8 lambs. The BP in lamb's diet increased the ruminal concentration of propionate (T4 and T8). The T8 lambs had greater serum activity of superoxide dismutase and glutathione transferase, and lower reactive oxygen species levels. We conclude that BP is a biotechnological additive with high nutritional potential.

Effects of the inclusion of açai oil in diet of prepartum Holstein cows on milk production, somatic cell counts and future lactation.

We measured the effects of açai oil in the diets of prepartum cows to evaluate health, milk production and quality. Sixteen Holstein cows were divided into two groups: SOY used as control, and AÇAI, test group. Occurred inclusion of 4% soybean or açai oils was provided in the concentrate starting at 20 days prepartum [d -20 to d 0 (partum-day)]. The AÇAI diet increased (P=0.01) milk production (d 10 and 20) and reduced somatic cell count (d 20). In milk, no effects were detected (P≥0.10) for concentration of fat, lactose or protein as well as in terms of serum concentration of calcium, albumin or triglycerides. AÇAI diet tended to increase (P=0.09) serum concentrations of total protein, glutathione transferase (d 4), and total antioxidant capacity (d 4 and 10) and increased (P≤0.05) globulin, gamma-glutamyl transferase, superoxide dismutase and glutathione peroxidase (d 4). Further, AÇAI diet reduced the serum concentration of creatine kinase (P≤0.05) (d 0, 4 and 10), reactive oxygen species (d 0 and 4) and lipoperoxidation (d 0) and tended to reduce aspartate transaminase activity (P=0.07; d 0 and 4). Açai oil in the diets in prepartum cows improved their health as well as milk production and quality.

Curcumin addition in diet of laying hens under cold stress has antioxidant and antimicrobial effects and improves bird health and egg quality.

Curcumin is an herbal component with several biological properties, and we highlight here the thermal stability, antioxidant and anti-inflammatory activity. We determined whether curcumin supplementation in the diets of laying hens under cold stress and naturally infected with Escherichia coli would control infection, and would have positive effects on overall health, as well as egg production and quality. We allocated 36 chickens that had been naturally infected with E. coli into two groups, with six replicates and three chickens per repetition: control group and curcumin group (200 mg curcumin/kg). The experimental period lasted 42 days, and fecal, blood and egg samples were collected at 1, 21 and 42 days We found that feces and eggs had lower total bacterial counts, E. coli counts and total coliform counts in the curcumin group at 21 and 42 days. In fresh eggs, the brightness and yellow intensity (b+) were significantly higher in the curcumin group. In stored eggs, higher specific gravity, albumen height and lower yolk pH were observed in the curcumin group. Fresh eggs collected and stored on day 42 showed lower levels of lipid peroxidation in the curcumin group, while the total antioxidant capacity in the stored eggs was significantly higher in the curcumin group. The curcumin group showed lower total leukocyte counts as a result of lower numbers of neutrophils and lymphocytes, as well as lower levels of total protein, alkaline phosphatase and alanine aminotransferase. Lower serum lipoperoxidation at 42 days was observed in the curcumin group, probably because of the higher activity of glutathione peroxidase and glutathione transferase in other words, because of antioxidant stimulation. Taken together, our findings suggest that curcumin supplementation in laying hens under cold stress and with colibacillosis has positive effects on infection control because of antioxidant stimulation.

Dog food production using curcumin as antioxidant: effects of intake on animal growth, health and feed conservation.

The objectives of this study were to produce dog food containing curcumin replacing synthetic antioxidants, to evaluate its beneficial effects on animal growth and health. Curcumin (100 mg/kg) was added after the extrusion process along with the other micronutrients. The final concentration of curcumin was 32.9 mg/kg. The control feed was composed of the same ingredients without curcumin. After a storage of 6 months, feed composition and pH did not differ; however, the feed with curcumin showed lower protein oxidation, lipid peroxidation and higher total antioxidant capacity. After 2 months of feed production, 12 young Beagle dogs received either curcumin-containing food (n = 6)  or the control diet (n = 6). The animals were fed twice a day using individual kennels. Blood samples were taken on d 1, 35 and 42. During the first 30 d of the study, the animals had natural infectious diseases that were controlled with anti-protozoals and antibiotics. Greater numbers of red blood cells were observed in dogs fed with curcumin (d 35 and 45), and there were greater numbers of white blood cells as a consequence of increased neutrophils on d 42. At the end of the experiment, a significant reduction in the number of lymphocytes was observed in dogs that ingested curcumin (d 42), suggesting an anti-inflammatory effect, manifested as a decrease in globulin levels. In the final 15 d of the experiment, the animals were clinical healthy. Higher serum levels of glucose, urea, triglycerides and cholesterol were observed in dogs fed with curcumin. Curcumin increased the activity of several antioxidant enzymes in addition to non-protein thiols and the total antioxidant capacity in the serum, consequently reducing levels of oxygen reactive species. Curcumin supplementation of dogs did not favour growth or weight gain. Neverthless, it was concluded that curcumin improved animal health, with emphasis on the stimulation of the antioxidant system and evidence of an anti-inflammatory effect.

Pathogenetic effects of feed intake containing of fumonisin (Fusarium verticillioides) in early broiler chicks and consequences on weight gain.

Fusarium verticillioides is often responsible for contamination of poultry feed with the mycotoxin fumonisin. The objective of the study was to determine whether fumonisin-contaminated feed in the early phase of broiler chicks causes oxidative imbalances and interferes with weight gain. One-day-old male Cobb 500 broiler chicks (n = 80) were divided into four treatments of 20 birds each, all of which were fed basal feed until the 11th day of age. From day 12, some birds were challenged with fumonisin in the feed: Control (T0) continued receiving the basal ration; treatments T1, T2, and T3 were given feed experimentally contaminated with fumonisin at concentrations of 2.5 ppm, 5 ppm and 10 ppm, respectively. After the 5th (day 17) and 10th (day 21) days, ten birds from each treatment were euthanized for blood and tissue collection to measure histopathological, biochemical and oxidative stress markers. All animals were weighed individually at the beginning of the experiment (day 12), and at 17 and 21 days of age. Birds that ingested 10 ppm of fumonisin (T3) had lower (P < 0.05) weight gain compared to those in T0. At 21 days, the body weights of the T1, T2 and T3 chicks were 1.3%, 8.97% and 18.7% lower, respectively, than those of T0. No histological lesions in the livers were observed for any treatment; however, higher levels of reactive oxygen species (ROS: day 21) and lipoperoxidation (LPO: days 17 and 21) were observed, associated with lower liver activity of the enzymes superoxide dismutase (SOD: day 21), glutathione peroxidase (GPx: day 17 and 21) and glutathione S-transferase (GST: day 21) when birds consumed 5 or 10 ppm of fumonisin. In serum, LPO levels and SOD and GPx activities were lower for groups consuming high doses of fumonisin in the diet (T2 and T3); ROS levels and GST activity were higher in these birds. Birds that consumed fumonisin-containing diets had lower levels of alanine aminotransferase, total protein and albumin (T3); as well as lower serum glucose levels (days 17 and 21), uric acid and triglycerides (day 21) in T3 than in T0. At 21 days, there were smaller crypt sizes and intestinal villi in birds that consumed high levels of fumonisin. These results suggest that fumonisin (10 ppm) in chick diet causes hepatic oxidative stress and impairs intestinal health, consequently negatively affecting weight gain.

Fumonisin-(Fusarium verticillioides)-contaminated feed causes hepatic oxidative stress and negatively affects broiler performance in the early stage: Does supplementation with açai flour residues (Euterpe oleracea) minimize these problems?

Fusarium verticillioides is often responsible for contamination of poultry feed with the mycotoxin fumonisin. The aim of this study was to determine whether oxidative stress caused by intake of fumonisin-contaminated feed affects broiler performance at an early stage of development, as well as to test whether the addition of açai residue flour to contaminated feed would minimize these negative effects of redox metabolism. Birds were divided into four groups, with four repetitions of five animals each: control (TC) - birds that received basal feed; TCA treatment - basal feed supplemented with 2% açai flour; TF treatment - feed experimentally contaminated with fumonisin (10 ppm); TFA treatment - fumonisin-contaminated feed (10 ppm) and supplemented with açai fluor (2%). The experiment lasted 20 days, that is, the first 20 days of the chicks' lives. At the end of the experiment, the birds were weighed, and blood, intestine and liver samples were collected. The TCA and TFA had greater body weights and weight gain than did TF. Further, TCA and TFA had lower feed conversion than did TF. Açai flour intake (TCA and TFA) stimulated albumin synthesis and reduced serum AST activity. Nitrate/nitrite (NOx) levels were higher in serum of fumonisin-challenged (TF) birds than in groups; NOx levels were also higher in the livers of all test groups (TF, TCA and TFA) than in TC. Serum glutathione S-transferase (GST) activity was lower in fumonisin-consuming groups (TF and TFA); this was different from what occurred in the liver, that is, higher GST activity in TF and lower activity in TFA than in TC. Catalase activity (CAT) was also higher in the fumonisin-challenged groups (TF and TFA) and the groups supplemented with açai flour (TCA) than in TC. Serum reactive species (RS) and TBARS (lipid peroxidation) levels in the liver were lower in birds supplemented with açai flour and exposed to fumonisin. These data suggest that the addition of açai flour in the feed of early chickens improves animal performance and minimizes the effects of hepatic oxidative stress in birds fed fumonisin-contaminated feed.

Impacts of Escherichia coli infection in young breeder chicks on the animal behavior and cerebral activity of purinergic and cholinergic enzymes involved in the regulation of molecules with neurotransmitter and neuromodulator function.

The objective of this study was to evaluate if infection by Escherichia coli in juvenile breeder chicks alters the activity of enzymes involved in neurotransmission and cerebral immunomodulation, including acetylcholinesterase (AChE), nucleoside triphosphate diphosphohydrolase (NTPDase), 5'-nucleotidase (5'NT) and adenosine deaminase (ADA), as well as their effects on the pathogenesis of the disease. We divided 20 growing breeder chicks into two groups (n = 10 per group). One group was experimentally infected with 1 mL of culture medium containing 1 × 108 CFU of E. coli intraperitoneally. The other was the negative control. On the tenth day after infection, the animals were euthanized and brain samples were collected. Macroscopically, pericarditis and hepatic congestion were observed in the birds, but without histopathological lesions in the encephalon although the bacterium was present in the cerebral cortex of all animals in the infected group (i.e., they were PCR-positive). The activity of AChE, NTPDase, 5'-NT and ADA were evaluated in the cerebral homogenates of the birds after 10 days of infection. AChE activity in the cerebral cortex was lower in the infected group than in the control; there was an increase in the activity of NTPDase, 5'-nucleotidase and ADA, possibly indicating greater hydrolysis of ATP (P < 0.001), ADP (P < 0.01) and AMP (P < 0.01), followed by increased adenosine deamination (P < 0.001). Despite these changes, no apparently diseased animals were observed throughout the experimental period. Therefore, such changes in enzymatic activity may affect the functioning of the central nervous system because these enzymes are responsible for extracellular regulation of molecules that act on neurotransmission and immunomodulation such as acetylcholine, ATP and adenosine.

Benefits of the inclusion of açai oil in the diet of dairy sheep in heat stress on health and milk production and quality.

The objective of this study was to determine whether the addition of açai (Euterpe oleracea) oil in the diets of lactating sheep under heat stress exerted beneficial effects on health as well as milk production and quality. Eighteen multiparous Lacaune sheep (2 or 3 parities; 28-30 days of lactation; average milk production of 1.7 L/sheep/day) were stratified by parity and milk production and were assigned randomly to 1 of 2 treatments (9 sheep/treatment): diet supplemented with 2% of soybean oil (SOY) or 2% of açai oil (AÇAI) in the concentrate for 14 days. The amount of oil added in the diet was equivalent to 0.65% of the total diet (dry matter basis). Blood and milk samples were collected on days 1, 10 and 14. On day 14, the AÇAI group sheep had lower serum concentrations of leukocytes, neutrophils, and lymphocytes than did the SOY group sheep. On day 14, AÇAI group sheep had lower serum concentration of triglycerides and urea, milk concentration of fat and total solid and milk lipid peroxidation than did SOY group sheep. However, on day 14, AÇAI group sheep had higher serum concentrations of glucose and globulin, serum and milk antioxidant capacity against peroxyl radicals, milk production and productive efficiency than did SOY group sheep. The fatty acids profile in milk did not differ between groups. These data suggest that açai oil improved the antioxidant activity in serum and milk and improved milk production and quality in dairy sheep under heat stress.

Cholinesterase as an inflammatory marker of subclinical infection of dairy cows infected by Neospora caninum and risk factors for disease.

The aim of this study was to evaluate the seroprevalence of Neospora caninum in dairy cows, as well as to verify the risk factors for N. caninum infection and inflammatory response in dairy cows. Using the indirect immunofluorescence reaction, the seroprevalence of neosporosis was determined to be 32.82%. Based on regression analysis, the presence of dogs at a farm increased the probability of a cow testing positive for N. caninum (OR = 20.01 [5.21-123.12]). These data suggest that N. caninum has a relevant prevalence in dairy cows of the Microregion of Rio do Sul (Brazil), with elevated frequencies of anti-N. caninum IgG. The data also suggest that the parasite is widely distributed in dairy herds of the micro-region, because 94.4% of properties screened had at least one seropositive animal. The principal risk factors for disease maintenance in herds may be considered the presence of dogs and absence of a diagnostic test when introducing new animals. Blood from these cows was used to measure variables related to the inflammatory response. Serum cholinesterase activity, as well as serum levels of globulins and C-reactive protein were higher in seropositive to N. caninum than in seronegative cows. Furthermore, the infection by parasite causes an intense inflammatory process, contributing to disease pathophysiology.

Effects of oral administration of copper capsules on helminth control in lactating dairy sheep: An effective alternative to replace conventional antiparasitics during lactation.

Two experiments were performed to determine whether oral administration of copper oxide capsules controlled helminthic infections in Lacaune sheep without acute collateral effects on animal health. In experiment 1, 48 multiparous lactating sheep (60.1 ±â€¯8.5 kg) were stratified according to initial number of eggs (Haemonchus contortus) per gram of feces (EPG) and were assigned randomly to 1 of two treatments (24 sheep/treatment): no oral administration (control) or oral administration of two copper capsules (treated; approximately 58 mg copper/kg body weight). Blood and fecal samples were collected on days 0, 15 and 45. Animals treated with copper capsules showed lower of EPG, eosinophils, acetylcholinesterase (AChE) in whole blood, and lower butyrylcholinesterase (BChE) activity in serum. Treated sheep had higher erythrocyte numbers, hemoglobin concentrations, hematocrit, and lymphocyte numbers. In experiment 2, 12 male lambs negative for helminths and coccidia were assigned randomly to one of two treatments (six lambs/treatment): control or treated (one copper capsule; approximately 58 mg copper/kg body weight); the experiment was designed to determine whether the results of experiment 1 were due to treatment or parasitism. Blood samples were collected on days 0, 5, 10 and 15 and fecal samples were collected on days 0, 7 and 15. Treated animals showed greater concentrations of lymphocytes; however, treatment had no effect on other hemogram variables, AChE and BChE activities, or levels of alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, creatinine, urea, albumin, total protein, and reactive oxygen species. These data suggest that copper capsules in dairy sheep efficiently controlled H. contortus infections. Treatment was not harmful to lambs during the first 15 days, i.e. there were no signs of acute toxicity.

Use of grape residue flour in lactating dairy sheep in heat stress: Effects on health, milk production and quality.

The objective of this study was to evaluate the effects of grape residue flour (GRF) on antioxidant activities, biochemistry variables, components of the immune system and milk production and quality of Lacaune sheep in heat stress. Twenty-seven multiparous lactating sheep [50 ±â€¯1.8 days (d) milking] were stratified by initial body weight, age, date of lambing and milk production and assigned randomly to 1 of 3 treatments (9 sheep/treatment): no GRF supplementation (control group) or supplementation at 1% (10 g/kg GRF) or 2% (20 g/kg GRF) of GRF (bark and seed) in the concentrate (grains and minerals mixture). Each ewe received 0.8 kg/d of concentrate, 3.6 kg/d of corn silage, and 0.25 kg/d of Cynodon spp hay. Milk production along with blood and milk samples were collected on d 1, 10 and 15. The 2% GRF sheep had increased serum concentrations of superoxide dismutase and glutathione peroxidase activity on d 15 compared to control sheep. Over time (d 10 to 15), lipid peroxidation was reduced in 2% GRF sheep. Total serum antioxidant capacity was greater in 2% GRF sheep compared to control sheep on d 10 and 15. Superoxide dismutase and glutathione peroxidase activity in milk samples were greater in 2% GRF sheep compared to control sheep. Supplementation with GRF did not affect milk production but GRF sheep were more efficient compared to control sheep. Protein and lactose concentrations were similar between treatments, but total solids and fat concentrations were greater in 2% GRF sheep compared to control sheep on d 15. Somatic cell count was reduced in GRF sheep compared to control sheep. In summary, supplementation with 2% GRF in dairy sheep in heat stress resulted in antioxidant and anti-inflammatory responses, which improved milk quality and reduced somatic cell count and lipid peroxidation.

Impact of colibacillosis on production in laying hens associated with interference of the phosphotransfer network and oxidative stress.

The objective of this study was to evaluate the productive impact of colibacillosis on laying hens and to investigate whether energetic metabolism and oxidative stress were involved in the pathogenesis of the disease. An experimental shed containing 270 laying hens of the Hy-Line lineage (32 weeks old) presented approximately 40% daily laying, and many birds presented with diarrhea and apathy followed by death. Necropsy revealed macroscopic lesions compatible with colibacillosis and infectious agent Escherichia coli was isolated from fecal samples of all birds in the infected group, as well as from tissue (ovary, liver and peritoneum). Sixteen chickens were selected for this study, divided into two groups: Control (animals without clinical alterations) and infected (with diarrhea and apathetic). E. coli isolates were subjected to the antimicrobial susceptibility testing according to the methodology approved by CLSI, 2018. This testing showed sensitivity to gentamicin, amoxicillin, norfloxacin and colistin. It was then determined that laying hens would be treated with norfloxacin (15 mg/kg) diluted in water offered at will to the birds for three days. Blood collections were performed via brachial vein after the diagnosis of E. coli (before starting treatment) and seven days after treatment. Three debilitated chickens died on the second day after initiating therapy. Before treatment, birds with clinical signs had higher levels of lipoperoxidation (LPO) and activities of antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx) than in the control group (asymptomatic animals). After treatment, LPO levels remained higher in birds that had clinical disease (infected group), whereas the activity of SOD and GPx enzymes did not differ between groups. Activity levels of creatine kinase (CK) and pyruvate kinase (PK) were higher in the group of chickens with clinical disease before treatment. Post-treatment, no differences were observed between groups in terms of CK; however, PK activity remained high in these animals. In the hens that died, there were lesions characteristic of avian colibacillosis, with ovary involvement, explaining the low laying activity of the birds at their peak of production. For 10 days after starting treatment, the percentage of laying increased to 90%. Therefore, we conclude that colibacillosis interferes with the phosphotransfer network by stimulating ATP production, in addition to causing oxidative stress of the birds during laying, that negatively affects health and productive efficiency.