Effects of Cold Exposure on Some Physiological, Productive, and Metabolic Variables in Lactating Dairy Goats

Low winter temperatures in some regions have a negative impact on animal performance, behavior, and welfare. The objective of this study was to evaluate some physiological, metabolic, and lactational responses of dairy goats exposed to cold temperatures for 3 weeks. Eight Murciano-Granadina dairy goats (41.8 kg body weight, 70 days in milk, and 2.13 kg/day milk) were used from mid-January to mid-March. Goats were divided into 2 balanced groups and used in a crossover design with 2 treatments in 2 periods (21 days each, 14 days adaptation and 7 days for measurements). After the first period, goats were switched to the opposite treatment. The treatments included 2 different controlled climatic conditions with different temperature-humidity index (THI) values. The treatments were: thermoneutral conditions (TN; 15 to 20 °C, 45% humidity, THI = 58 to 65), and cold temperature (CT; −3 to 6 °C, 63% humidity, THI = 33 to 46). Goats were fed ad libitum a total mixed ration (70% forage and 30% concentrate) and water was freely available. Goats were milked at 0800 and 1700 h. Dry matter intake, water consumption, rectal temperature, and respiratory rate were recorded daily (days 15 to 21). Body weight was recorded at the start and end of each period. Milk samples for composition were collected on 2 consecutive days (days 20 and 21). Insulin, glucose, non-esterified fatty acids (NEFA), ß-hydroxybutyrate (BHB), cholesterol, and triglycerides were measured in blood on d 21. Compared to TN goats, CT goats had similar feed intake, but lower water consumption (−22 ± 3%), respiratory rate (−5 ± 0.8 breaths/min), and rectal temperature (−0.71 ± 0.26 °C). Milk yield decreased by 13 ± 3% in CT goats, but their milk contained more fat (+13 ± 4%) and protein (+14 ± 5%), and consequently the energy-corrected milk did not vary between TN and CT goats. The CT goats lost 0.64 kg of body weight, whereas TN goats gained 2.54 kg in 21 days. Blood insulin and cholesterol levels were not affected by CT. However, values of blood glucose, NEFA, hematocrit, and hemoglobin increased or tended to increase by CT, whereas BHB and triglycerides decreased. Overall, CT goats produced less but concentrated milk compared to TN goats. Despite similar feed intake and blood insulin levels CT goats had increased blood glucose and NEFA levels. The tendency of increased blood NEFA indicates that CT goats mobilized body fat reserves to cover the extra energy needed for heat production under cold conditions

Prenatal heat stress effects on gestation and postnatal behavior in kid goats

Consequences of heat stress during pregnancy can affect the normal development of the offspring. In the present experiment, 30 Murciano-Granadina dairy goats (41.8 ± 5.7 kg) were exposed to 2 thermal environments varying in temperature-humidity index (THI) from 12 days before mating to 45 days of gestation. The environmental conditions were: gestation under thermal-neutral (TN; THI = 71 ± 3); and gestation under heat stress (HS; THI = 85 ± 3) conditions. At 27 ± 4 days old, female kids exposed to in utero TN (IUTN; n = 16) or in utero HS (IUHS; n = 10) were subjected to 2 tests: arena test (AT) and novel object test (NOT), the latter was repeated at 3 months of age. Additionally, 8 months after birth, a subset of IUTH and IUHS growing goats (n = 8 each; 16.8 ± 3.4 kg BW) were exposed to 2 environmental conditions in 2 consecutive periods: a basal thermal-neutral period (THI = 72 ± 3) for 7 days, and a heat-stress period (THI = 87 ± 2) for 21 days. In both periods, feeding, resting, posture, and thermally-associated behaviors were recorded. The gestation length was shortened by 3 days in GHS goats. In the AT, IUHS kids showed a lower number of sniffs (P < 0.01) compared to IUTN. In the NOT, IUHS kids also tended to show a lower number of sniffs (P = 0.09). During heat exposure, IUTN and IUHS growing goats spent more time resting and exhibited more heat-stress related behaviors such as panting and drinking (P < 0.001); however, no differences were observed between both groups. In conclusion, heat stress during the first third of pregnancy shortened gestation length and influenced the exploratory behavior of the kids in the early life. However, behavior responses to heat stress during the adulthood were not affected by the in utero thermal treatment

Porcine Digestible Peptides (PDP) in Weanling Diets Regulates the Expression of Genes Involved in Gut Barrier Function, Immune Response and Nutrient Transport in Nursery Pigs

CRAG 10.3390/ani10122368This study was conducted to investigate the effects of dietary supplementation of porcine digestible peptides (PDP), spray-dried plasma (SDP), or a combination of both, on growth performance and the expression of genes related to intestinal function of weaned pigs. A total of 180 piglets (trial 1) and 198 piglets (trial 2) were used to evaluate the partial substitution of soybean ingredients with 2% SDP or 2% PDP (trial 1), and with 3% SDP or the combination of 1% SDP and 2% PDP (SDP-PDP; trial 2) during the pre-starter period (0-14 days). The gene expression of 56 genes was quantified in a qPCR platform in jejunum and ileum samples obtained from piglets 14 d after weaning (trial 2). Piglets fed SDP, PDP and SDP-PDP had a higher body weight (BW), average daily gain (ADG) and feed efficiency (G:F) than the soybean control on day 14 (p < 0.05). In addition, the combination of SDP and PDP upregulated ten genes in jejunum samples (p < 0.05) related to intestinal function. More research is needed to confirm that gene expression upregulation by PDP in combination with SDP has an impact on intestinal function and to elucidate its underlying mechanisms

Porcine Digestible Peptides (PDP) in Weanling Diets Regulates the Expression of Genes Involved in Gut Barrier Function, Immune Response and Nutrient Transport in Nursery Pigs

This study was conducted to investigate the effects of dietary supplementation of porcine digestible peptides (PDP), spray-dried plasma (SDP), or a combination of both, on growth performance and the expression of genes related to intestinal function of weaned pigs. A total of 180 piglets (trial 1) and 198 piglets (trial 2) were used to evaluate the partial substitution of soybean ingredients with 2% SDP or 2% PDP (trial 1), and with 3% SDP or the combination of 1% SDP and 2% PDP (SDP-PDP; trial 2) during the pre-starter period (0-14 days). The gene expression of 56 genes was quantified in a qPCR platform in jejunum and ileum samples obtained from piglets 14 d after weaning (trial 2). Piglets fed SDP, PDP and SDP-PDP had a higher body weight (BW), average daily gain (ADG) and feed efficiency (G:F) than the soybean control on day 14 (p < 0.05). In addition, the combination of SDP and PDP upregulated ten genes in jejunum samples (p < 0.05) related to intestinal function. More research is needed to confirm that gene expression upregulation by PDP in combination with SDP has an impact on intestinal function and to elucidate its underlying mechanisms

Effects of thermal stress on dairy goats and their offspring

Resums pendent

Effects of thermal stress on dairy goats and their offspring

Resums pendent

Effects of thermal stress on dairy goats and their offspring

Departament responsable de la tesi: Departament de Ciència Animal i dels Aliments.In the present thesis, 3 experiments were carried out using Murciano-Granadina dairy goats under low temperature (LT; Exp. 1) and heat stress (HS; Exp. 2 and 3) conditions in order to evaluate the physiological, metabolic, productive and behavioral responses. In Exp. 1, 8 dairy goats in mid-lactation were randomly allocated into 2 groups: thermal-neutral (TN; 15 to 20°C) and LT (-3 to 6°C) in a crossover design with 2 treatments in 2 periods (21 d each). Body weight, feed intake, water consumption, milk production, rectal temperature (RT), respiratory rate (RR), as well as blood insulin, glucose, non-esterified fatty acids (NEFA), beta- hydroxybutyrate (BHB), cholesterol and triglycerides were measured. Compared to TN goats, LT goats had similar feed intake, but lower (P < 0.05) water consumption (−23%), RR (−6 breaths/min) and RT (−0.32°C). Milk of LT goats had greater (P < 0.05) contents of protein (+10%), fat (+12%) and lactose (+4%) than TN goats. The LT goats lost −0.45kg BW, whereas TN goats gained 2.2 kg (P < 0.05). Values of blood glucose, NEFA, hematocrit and hemoglobin increased (P < 0.05) by LT, whereas BHB and triglycerides decreased (P < 0.05). In Exp. 2, 30 dairy goats were exposed to 2 treatments: TN (15 to 20°C), and HS (30 to 37°C) from 12 days before mating to day 45 of gestation. Feed intake, RT and RR were recorded. After kidding, litter size, birth weight and weaning weight of kids were registered. At 27 4 days old, female kids exposed to in utero TN (IUTN; n = 16) and HS (IUHS; n = 10) were subjected to 2 tests: arena test (AT) and novel object test (NOT). In both tests, kids were entered a 4x4 m2 arena and the distance travel, number of squares entered, jumps and sniffs of the arena were recorded. At 8 months old, a subset of growing goats (n = 8) from each group (IUTN and IUHS) were exposed to 2 environmental conditions in 2 consecutive periods: a TN period for 7 d at 15-20 °C (P1), and then HS for 21 d at 30-37°C (P2). Feeding behavior and other activities (drinking, exploring, and grooming) and resting behaviors, as well as posture were recorded. Compared with TN, gestation length was shortened by HS (-3d; P < 0.01). In the AT, IUHS kids showed a lower number of sniffs (P < 0.01) than IUTN. Further, during HS (P2), both IUTN and IUHS goats spent more time resting, panting and drinking (P < 0.001) with no differences between both groups. In Exp. 3, the same goats (IUTN; n =8, and IUHS; n = 8) used for HS behavior in Exp. 2 were used. Body weight, feed intake, water consumption, RT, RR as well as blood glucose, insulin, NEFA, BHB, cholesterol and triglycerides were measured. In addition, 4 goats from each treatment were subjected to a glucose tolerance test (GTT), insulin tolerance test (ITT), and an epinephrine challenge, each one performed once during P1 and P2. Regardless the in utero thermal treatment, HS resulted in increased (P < 0.01) RT, RR and water consumption, but decreased (P < 0.05) body weight gain. However, IUHS goats needed 10% less (P < 0.05) RR to keep similar RT to IUTN goats. Compared to IUTN, IUHS goats had greater glucose area under curve at 45 min (P = 0.077) and 90 min (P = 0.056), and lower (P < 0.05) insulin clearance rate in response to the GTT. In conclusion, LT goats had similar DM intake to TN goats, but their milk contained greater fat and protein. The LT goats covered the extra energy needed for heat production by mobilizing body fat reserves as indicted by greater blood NEFA levels. Heat stress during the first third of pregnancy shortened pregnancy length, and modified some behavioral, physiological and metabolic responses to various stimulators, including HS during the postnatal life

Effects of Cold Exposure on Some Physiological, Productive, and Metabolic Variables in Lactating Dairy Goats

Low winter temperatures in some regions have a negative impact on animal performance, behavior, and welfare. The objective of this study was to evaluate some physiological, metabolic, and lactational responses of dairy goats exposed to cold temperatures for 3 weeks. Eight Murciano-Granadina dairy goats (41.8 kg body weight, 70 days in milk, and 2.13 kg/day milk) were used from mid-January to mid-March. Goats were divided into 2 balanced groups and used in a crossover design with 2 treatments in 2 periods (21 days each, 14 days adaptation and 7 days for measurements). After the first period, goats were switched to the opposite treatment. The treatments included 2 different controlled climatic conditions with different temperature-humidity index (THI) values. The treatments were: thermoneutral conditions (TN; 15 to 20 °C, 45% humidity, THI = 58 to 65), and cold temperature (CT; −3 to 6 °C, 63% humidity, THI = 33 to 46). Goats were fed ad libitum a total mixed ration (70% forage and 30% concentrate) and water was freely available. Goats were milked at 0800 and 1700 h. Dry matter intake, water consumption, rectal temperature, and respiratory rate were recorded daily (days 15 to 21). Body weight was recorded at the start and end of each period. Milk samples for composition were collected on 2 consecutive days (days 20 and 21). Insulin, glucose, non-esterified fatty acids (NEFA), ß-hydroxybutyrate (BHB), cholesterol, and triglycerides were measured in blood on d 21. Compared to TN goats, CT goats had similar feed intake, but lower water consumption (−22 ± 3%), respiratory rate (−5 ± 0.8 breaths/min), and rectal temperature (−0.71 ± 0.26 °C). Milk yield decreased by 13 ± 3% in CT goats, but their milk contained more fat (+13 ± 4%) and protein (+14 ± 5%), and consequently the energy-corrected milk did not vary between TN and CT goats. The CT goats lost 0.64 kg of body weight, whereas TN goats gained 2.54 kg in 21 days. Blood insulin and cholesterol levels were not affected by CT. However, values of blood glucose, NEFA, hematocrit, and hemoglobin increased or tended to increase by CT, whereas BHB and triglycerides decreased. Overall, CT goats produced less but concentrated milk compared to TN goats. Despite similar feed intake and blood insulin levels CT goats had increased blood glucose and NEFA levels. The tendency of increased blood NEFA indicates that CT goats mobilized body fat reserves to cover the extra energy needed for heat production under cold conditions