Mortality in mink kits from birth to weaning

In 1988, a necropsy survey of the pattern and major causes of mortality in mink kits from birth to weaning was undertaken. The overall preweaning mortality rate was 20%. Mortalities occurring within the first three days after birth accounted for 91% of submissions, and 78% of the kits in this age group had no lesions or bacterial isolates. The average weight of kits which died within one day of birth (7.9 g) was significantly lower than the average birthweight of healthy kits (10.7 g). In kits under four days of age and with lesions, the most common diagnoses were dystocia (12%), systemic infection (4%), anasarca (2%), and congenital defects (1%). In unweaned kits four days of age or older, the most common diagnoses were systemic infection (19%), external trauma (6%), dystocia (5%), and cervical adenitis (2%).     

A review of foal diarrhoea from birth to weaning

Diarrhoea is among the most common clinical complaints in foals. Aetiologies, diagnostic testing and recommended interventions for specific causes of enterocolitis are summarised. Many mild to moderately affected foals can be managed in an ambulatory setting, while others will benefit from more intensive care at a referral centre.     

Evaluation of site and age of weaning on pig growth performance

Site-segregated early weaning (SSEW) refers to the practice of weaning pigs from the sow at an early age and placing them in a nursery that is physically isolated from the breeding herd. An experiment involving 369 pigs was conducted at the Prairie Swine Center to investigate the impact of SSEW on pig performance when the herd of origin has a high health status and when housing and management conditions are kept as similar as possible across weaning regime. Three treatments were compared: weaning at 21+/-3 d and keeping the pigs on-site in an all-in-all-out nursery room (Control), weaning at 12+/-2 d of age and keeping the pigs on-site in a separate but identical all-in-all-out nursery room (OSEW), or weaning at 12+/-2 d of age and moving the pigs off-site to an all-in-all-out nursery room located 16 km from the Center (SSEW). Ventilation, feed, penning, feeders, and drinkers were kept as similar as possible for all treatments. Off-site weaning improved 56-d body weight (P < .05) by 12.5 and 8.3% compared with OSEW and Control, respectively. The improvement appeared to be the result of improvements primarily in feed intake but also due to enhanced efficiency of nutrient utilization. This experiment confirms that SSEW results in significant improvements in 56-d weights, even when the herd of origin has a relatively high health status.     

Lamb survival analysis from birth to weaning in Iranian Kermani sheep

Survival records from 1,763 Kermani lambs born between 1996 and 2004 from 294 ewes and 81 rams were used to determine genetic and non-genetic factors affecting lamb survival. Traits included were lamb survival across five periods from birth to 7, 14, 56, 70, and 90 days of age. Traits were analyzed under Weibull proportional hazard sire models. Several binary analyses were also conducted using animal models. Statistical models included the fixed class effects of sex of lamb, month and year of birth, a covariate effect of birth weight, and random genetic effects of both sire (in survival analyses) and animal (in binary analyses). The average survival to 90 days of age was 94.8%. Hazard rates ranged from 1.00 (birth to 90 days of age) to 1.73 (birth to 7 days of age) between the two sexes indicating that male lambs were at higher risk of mortality than females (P < 0.01). This study also revealed a curvilinear relationship between lamb survival and lamb birth weight, suggesting that viability and birth weight could be considered simultaneously in the selection programs to obtain optimal birth weight in Kermani lambs. Estimates of heritabilities from survival analyses were medium and ranged from 0.23 to 0.29. In addition, heritability estimates obtained from binary analyses were low and varied from 0.04 to 0.09. The results of this study suggest that progress in survival traits could be possible through managerial strategies and genetic selection.     

小肽制剂对生长育肥猪生产性能的影响

选择平均体重约15kg左右的三元杂交生长猪24头,随机分成三个处理组,每个处理设两个重复,每个重复4头仔猪。试验Ⅰ组和试验Ⅱ组分别在日粮中添加0 5%和0 3%的小肽制剂,经过30d试验,与对照组相比平均日增重分别提高8 34%(P<0 05)和3 91%(P>0 05),料肉比降低8 40%和5 04%,生长猪腹泻率分别降低5 16%(P<0 05)和4 45%(P<0 05)。     

早期断奶对羔羊生长发育的影响

将120只10～15 日龄的德国美利奴羊(♂)×小尾寒羊(♀)杂交一代羔羊随机分为Ⅰ、Ⅱ、Ⅲ、Ⅳ组,Ⅰ组于35 日龄断奶、Ⅱ组于45日龄断奶、Ⅲ组于60 日龄断奶、Ⅳ组于90日龄断奶.结果表明:60 d体重4组间无显著差异(P>O.05);90 d体重,Ⅱ、Ⅲ、Ⅳ组极显著(P(0.01)高于Ⅰ组,Ⅱ、Ⅲ、Ⅳ组间差异不显著(P>O.05).30～60日龄日增重,Ⅱ、Ⅲ、Ⅳ组极显著高于Ⅰ组(PO.05).45日龄断奶,羔羊体质健壮,抗病能力较强,综合效益高,为最佳断奶时间.     

Relationship between weaning age and antibiotic usage on pig growth performance and mortality

A total of 2,184 pigs (DNA 600 × PIC L42) were used to evaluate the effects of weaning age and antibiotic (AB) use on pig performance from weaning to marketing in a commercial production system. Experimental treatments were arranged in a 3 × 2 factorial with main effects of weaning age (18.5, 21.5, or 24.5 d of age) and with the use of ABs or an antibiotic-free (NAE) program. At birth, pigs were ear tagged, and the date of birth and sex recorded. Pigs were weaned from a 4,000-sow farm over four consecutive weeks. Four weaning batches (one per week) of 546 pigs were used. Each weaning batch had one-third of pigs of each weaning age. Pigs were placed in pens by weaning age and then randomly assigned to an AB or NAE program. There were 14 replicate pens per treatment and 26 pigs per pen (13 barrows and 13 gilts). Pigs allocated to the AB program were fed a diet containing 441 mg/kg chlortetracycline (CTC) from day 8 to 21 postweaning. They were also administered 22 mg/kg of body weight (BW) of CTC via drinking water for five consecutive days after a porcine respiratory and reproductive syndrome outbreak during week 7 after weaning. In the first 42 d postweaning, increasing weaning age improved (linear, P < 0.001) BW at day 42, average daily gain (ADG), and average daily feed intake (ADFI). From weaning to 197 d of age, increasing weaning age increased (linear, P < 0.001) ADG and ADFI. Pigs on the AB program had greater (P = 0.031) ADG and ADFI compared with NAE pigs. An interaction (linear, P = 0.005) was observed for feed efficiency (G:F). When ABs were provided, increasing weaning age did not result in any change in G:F; however, in the NAE program, increasing weaning age increased G:F. Pigs on the AB program had lower (P < 0.001) total losses (mortality and removals) than those on the NAE program. Increasing weaning age marginally (linear, P = 0.097) decreased total losses. Increasing weaning age decreased (quadratic, P < 0.001) the number of pigs treated with an injectable AB but the AB program did not (P = 0.238). The weight sold (at 197 d of age) per pig weaned was increased (linear, P = 0.050) by increasing weaning age and by using AB in feed and water (P = 0.019). In summary, increasing weaning age linearly improved most of the pig performance criteria and relatively the short-term use of ABs reduced mortality and removals with both factors contributing to increased weight sold per pig weaned.     

Prenatal stress effects on pig development and response to weaning

Exposing a pregnant sow to stress has been shown to affect the resulting offspring. Our objective was to determine if rough handling of pregnant sows altered the physiology of her offspring and if these alterations were different from an experimentally induced model of prenatal stress. Sow treatments consisted of i.v. injections of ACTH (1 IU/kg of BW), exposure to rough handling for 10 min (Rough), or no treatment (Control) once a week during d 42 to 77 of gestation. To determine the plasma cortisol response to treatments, blood (5 mL) was collected from 30 sows after treatment administration. To conduct the prenatal stress study, a separate group of 56 sows was used in 1 of 4 replicates. At birth, production data were collected for each litter, including birth weight, number born, anogenital distance, and pig viability. At weaning, pigs were blocked by BW and sex, and placed in a nursery pen of 6 pigs, with 2 pigs from each treatment group. To assess the effect of treatments on cortisol, corticosteroid-binding globulin (CBG), and hematological cell profiles, blood was collected every other day for 10 d after weaning. Application of treatments caused plasma cortisol concentrations to be greatest in ACTH sows compared with Control sows (P < 0.001), with Rough sows having intermediate values (P = 0.07). Treatments did not affect the number of pigs born, number of stillborn, or pig viability (P > 0.40). The ratio of cortisol to CBG did not differ between treatments (P = 0.09). Hematological variables did not differ between treatments (P > 0.19). Pigs born to ACTH sows had a smaller anogenital distance compared with controls (P < 0.03), with pigs from Rough sows being intermediate. Our data indicate that swine exposed to prenatal stress (ACTH injection) can have alterations in sexual morphology without effects on growth or the immune cell populations measured in this study.     

断奶后日粮中超剂量地添加植酸酶可提高仔猪的生产性能

提高断奶仔猪的生产性能一直是养猪生产系统关注的重点,因为仔猪有一个最佳的生长开端很重要.最大化地促进仔猪21 d断奶时达到最大的生产性能被认为是与其终生生产性能以及生产者最终盈利密切相关.这常常导致给断奶仔猪使用专门的开食料,这种饲料通常比之后使用的保育期饲料更为复杂,含有高比例的动物蛋白和乳清产品.传统上,这些专用的断奶日粮在断奶早期一般添加较低水平的植物源性蛋白.     

Using genetic evaluations for growth and maternal gain from birth to weaning to predict energy requirements of Line 1 Hereford beef cows

The maintenance energy required to sustain the cow herd is a major cost of beef production. This work proposes modifying parameter estimates for a population-specific lactation curve with genetic evaluations for the maternal genetic effect on calf gain from birth to weaning to provide inputs for a commonly used prediction of energy requirement. Daily milk production (y) was modeled as a function of stage of lactation (T, d) using the function y = AT(B)exp(-CT) modified to incorporate effects of genetic evaluation for the maternal effect on calf gain from birth to weaning and age of dam. A 1-kg increase in predicted maternal breeding value for calf gain from birth to weaning from within-herd genetic evaluation increased the lactation curve parameter A by 10.3+/-4.6% and reduced the B parameter by 1.0+/-0.6%. Similarly, a 1-kg increase in maternal breeding value for gain from birth to weaning from national cattle evaluation increased the A parameter by 1.7+/-0.2%. Corresponding estimates of peak milk yield and time of peak lactation were derived for individual animals from their genetic evaluation. Additional inputs for predicting maintenance energy requirements were derived from genetic evaluations for birth weight and mature size. The methodology is demonstrated using genetic evaluations of sires from the Miles City Line 1 Hereford population. Further refinement and application of this methodology may facilitate characterization of beef cattle seedstock for their potential genetic contributions to profitability.     

人工乳对早期断奶仔猪生长性能影响的研究

早期断奶仔猪常出现断奶应激,导致腹泻。“102人工乳”具有多种生理功能,可显著降低断奶应激,减少腹泻,促进生长。因此通过饲喂人工乳,可以达到减少断奶应激、促进仔猪生长的目的。     

Calf health from birth to weaning. II. Management of diarrhoea in pre-weaned calves

Calfhood diseases have a major impact on the economic viability of cattle operations. The second of this three part review series considers the management of diarrhoeic diseases in pre-weaned calves. In neonatal calf diarrhoea, oral rehydration therapy is the single most important therapeutic measure to be carried out by the farmer and is usually successful if instigated immediately after diarrhoea has developed. Continued feeding of milk or milk replacer to diarrhoeic calves is important, to prevent malnourishment and weight loss in affected calves. Indiscriminative antibiotic treatment of uncomplicated diarrhoea is discouraged, whereas systemically ill calves can benefit from systemic antibiotic treatment for the prevention of septicaemia or concurrent diseases. Ancillary treatments and specific preventive measures are discussed. Eimeriosis has a high economic impact on the farming industries due to direct cost of treatment and calf losses, but especially due to decreased performance of clinically as well as sub-clinically affected animals. Emphasis lies on prophylactic or metaphylactic treatment, since the degree of damage to the intestinal mucosa once diarrhoea has developed, makes therapeutic intervention unrewarding.     

Calf health from birth to weaning. I. General aspects of disease prevention

Calfhood diseases have a major impact on the economic viability of cattle operations. This is the first in a three part review series on calf health from birth to weaning, focusing on preventive measures. The review considers both pre- and periparturient management factors influencing calf health, colostrum management in beef and dairy calves and further nutrition and weaning in dairy calves.     

Effect of starter feeding program on growth performance and gains of body components from weaning to market weight in swine

Three experiments were conducted to test the hypothesis that different starter feeding programs (High, high quality; Low, low quality) will affect growth performance and body composition of pigs from weaning to market weight and that this effect may be influenced by gender (barrows or gilts) and breed (F, Yorkshire-Duroc x Hampshire; P, PIC Camborough 15 x PIC line 405). In Exp. 1, 21 +/- 4-d-weaned F pigs (n = 90) were used in a 2 (High or Low) x 2 (barrows or gilts) factorial design. In Exp. 2, 21 +/- 3-d-weaned pigs (n = 184) were used in a 2 (F or P) x 2 (High or Low) x 2 (barrows or gilts) factorial design. In Exp. 3, 21 F pigs from each gender and feeding program treatment were killed at d 0, 3, 7, 14, 42, 82, or 152 postweaning for evaluating body composition. Two starter feeding programs (High or Low) were applied to pigs for 6 wk postweaning. Pigs from both High and Low treatments were provided the same corn-soybean meal-based diets for the growing and finishing periods. Although the ADG of all pigs receiving the High treatment during the early starter period were higher (P < .01) than those of the Low, the terminal BW of F barrows were similar between High and Low (Exp. 1 and 2) and those of gilts were similar between High and Low (Exp. 2) (P > .80). However, the BW of P pigs receiving the High treatment, regardless of gender, tended to be heavier than those receiving the Low (Exp. 2) and F barrows receiving the High treatment tended to be heavier than those receiving the Low (Exp. 1). For the first 7 d postweaning, the High-fed pigs gained more protein (P < .05) and lost less fat (P < .05) than Low-fed pigs. During the growing-finishing period, the Low-fed pigs exhibited compensatory protein gain and achieved a body protein content similar (P < .60) to High-fed pigs by termination. Protein gains from weaning to termination between High- and Low-fed pigs were not different in Exp. 2 and 3. The protein gain of gilts was higher (P < .05) than that of barrows. Similarly, fat gain within genders was not affected by starter feeding program. Fat gain of gilts, however, was lower (P < .08) than that of barrows in Exp. 3. In conclusion, the nutritional quality of the starter feeding program affected growth performance immediately after weaning but did not affect protein gain over the entire production period.     

Selenium dynamics in the blood of lambs from birth to weaning using traditional rearing technics]

The dynamics of selenium in the blood serum of 20 lambs of the Merino breed, traditionally reared, was followed from birth to weaning at the age of 110 days. Results of the observations revealed that the highest concentration of serum selenium was determined in lambs just after delivery (0.25 ppm) and the level was maintained throughout the period of colostral nutrition. In the period between the 15th and 60th day low selenium values (0.06-0.13 ppm) were recorded, which implies a critical period in relation to the origin of muscular dystrophy. At the end of the observations there appeared a significant selenium content increase in the blood serum of lambs.